To understand the basic plumbing system of a
pool or spa, you must follow the path of the water.
The water from the pool or spa, not both at
the same time, enters the equipment system through a main drain on
the floor, through a surface skimmer, or through a combination of
both main drain and skimmer. It travels to a three-port valve (if
there is no spa, there will be no such valve) and into the pump,
which is driven by the attached motor. From the pump, the water
travels through a filter, then to the heater, and back through
three-port valves to the pool or spa return lines.
The purpose of the skimmer, as the name
implies, is to pull water into the system from the surface with a
skimming action, pulling in leaves, oil, and dirt before they can
sink to the bottom of the pool, there by providing a conveniently
located suction line for vacuuming the pool. Most skimmers today are
molded, one-piece plastic units. Older pools have built-in-place
concrete skimmers. Some pools have more than one skimmer.
Most skimmers are built into the deck, and are
accessed through a cover on top (the cover will be plastic or
concrete) or by reaching into the skimmer through the opening that
faces the pool itself. Some, as with portable or above ground pools,
are separate units that hang on the edge of the pool (in the water
or outside of it). Redwood hot tubs use a flat, vertical skimmer
that has no basket but skims the surface and pulls any floating
debris to a plastic screen. Some portable spa skimmers have a
cartridge filter built in. Some pool skimmers include automatic
water level controls and automatic chlorinators.
The water pours over a floating weir that
allows debris to enter, but when the pump is shut off and the
suction stops, the weir floats into a vertical position, preventing
debris from floating back into the pool. Some skimmers have no such
weir and use a floating barrel as part of the skimmer basket. The
purpose of the basket is to collect leaves and large debris so they
can then be easily removed. The disadvantage of both types of weirs
is that leaves can cause them to jam in a fixed position, thus
preventing water from flowing into the skimmer. When this happens,
the pump will lose prime and run dry, causing damage to its
components. Therefore, during windy periods it might be better to
remove the weir from the skimmer to prevent such problems.
By the way, you should exercise care when
working around the skimmer when the pump is on. Keep small objects
away from the skimmer opening when the basket is removed and
especially keep your hands from covering that suction hole for it
may be dangerous. You may invariably end up clogging the pipe at
some turning point where leaves, hair, and debris later catch and
close off the pipe completely.
There are two types of skimmer plumbing. The
first one has a single visible suction port or opening. Actually the
pipe from the main drain and the pipe from the skimmer connect just
below the visible opening and a combination diverter is inserted to
regulate the amount of suction from one or the other. A neck on the
diverter extends up from the skimmer bottom for attaching your
vacuum hose when cleaning the pool.
The value of this system is that when
vacuuming the pool, you can divert all of the pump suction to the
skimmer bottom, in effect, shutting off the main drain. The diverter
also has a nipple aligned horizontally to the opening. Usually when
the nipple faces away from the pool, the flare on the bottom of the
diverter closes the main drain pipe and all of the suction from the
pump is now at the skimmer. When the nipple faces toward the pool,
the body of the diverter closes the pipe from the skimmer and all of
the suction is now at the main drain. Choice between these two
settings will divide suction between the skimmer and main drain.
Depending on needs a pool has its own
settings. For example, if the pool gets more leaves than dirt, the
diverter should be set to make the suction in the skimmer stronger
than in the main drain. That will help the skimmer pull the leaves
into the skimmer basket. If the pool tends to get more dirt or sand
than leaves, the diverter should be set to strengthen the main drain
suction. When dirt falls to the bottom of the pool, the strong
suction from the main drain will pull the dirt toward it. This is
also helpful when brushing the pool bottom, because suspended dirt
will be pulled into the main drain.
Diverter units are made of plastic or bronze.
The bronze diverter are heavier and better than the plastic ones. If
the suction from the pump is not strong, the plastic ones tend to
come loose and float out during vacuuming . They also tend to rotate
in the skimmer as you work, changing the amount of suction in the
skimmer from what you have set.
The other type of skimmer plumbing has two
separate ports, one pipe that goes directly to the main drain or to
an equalizer line, while the other goes directly to the pump.
Usually the port farthest from the pool edge is the pipe that goes
to the pump, and the port closest to the pool goes to the main drain
or equalizer line. An equalizer line is simply a pipe that extends
from the skimmer bottom down 18 to 24 inches and through the pool
wall just below the skimmer. In this type of skimmer, a diverter
plate regulates the suction between the main drain and the skimmer.
In both styles of skimmer, the idea is that if
the pool runs low on water, the pump can pull water from the bottom
of the pool via the main drain instead of the empty skimmer, or from
the side of the pool below the skimmer in the case of the equalizer
line, so the pump will not run dry.
Some older (often concrete) skimmers have
odd-sized ports that can't accommodate your vacuum hose. In these
cases, a special cover plate can create a generic adapter.
The main drain has one or more plumbing ports.
One port feeds a pipe to the pump. In a spa, there might be several
ports for several pipes leading to different pumps (for jet action).
Another port is a one-way valve or the check
valve that allows water that might collect under the pool to enter
the pool, but no water can flow out. Water collecting under the pool
creates extreme upward pressure that can crack the pool. This
pressure, called hydrostatic pressure, is relieved by this valve.
Hydrostatic pressure is an important
consideration when planning to drain a pool for any reason.
Obviously it is not wise to drain a pool completely during the rainy
season or if there is any other suspicion of groundwater.
In some spas, there might be more than one
main drain so that if one becomes covered with a foot or hand, water
is pulled from the other, avoiding injury to the bather. These
drains are usually located at least 12 inches apart. Because spas
are relatively shallow, strong suction can create a whirlpool
effect. To prevent this, many spa main drains are fitted with
anti-vortex drain covers which are slightly dome-shaped with the
openings located around the sides of the dome.
Obviously in a pool where the main drain is
very deep, this is not a concern, so safety suction lines are not
added. Also, the suction in a pool is usually divided between the
main drain and the skimmer, so one is not dangerously stronger than
the other. Pool main drain covers are flat with the openings on top.
The drain area is covered by a grate, usually 8 to 12 inches in
diameter that screws or twist-locks into a ring that has been
plastered into the pool bottom.
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Before proceeding to specific instructions on
working with PVC plastic, galvanized, or copper plumbing, here are a
few general guidelines that should be taken into consideration,
regardless of the material you are using.
Measure the pipe run carefully, particularly
if you are repairing a section between plumbing that is already in
place. In measuring, remember to include the amount of pipe that
fits inside the connection fitting, usually about 1-1/2 inches at
When working on in-place plumbing, support
your work by building up wood or bricks under the pipe on each side
of your work area. This prevents vibration as you cut, which can
damage pipes or joints further down the line. Also, unsupported pipe
sags and binds when you cut it. That is, as you cut, it pinches the
saw blade making cutting difficult.
Threaded fittings are obvious and simple;
however to prevent leaks from occurring in these connections,
carefully cover the male threads with PTFE tape and tighten the
fitting as far as possible without cracking. PTFE tape fills the
gaps between the threads and prevent leaking. Apply the tape over
each thread twice, pulling it tight as you go so you can see the
threads. Apply the tape clockwise as you face the open end of the
male threaded fitting. If you apply the tape backwards, when you
screw on the female fitting, the tape will skid off the joint.
Another method of sealing threads is to apply
joint stick or pipe dope. Joint stick is a stick of a gum-like
substance that works like PTFE tape. Rub the joint stick over the
threads so that the gum fills the threads. Apply pipe dope the same
way. The only difference is that dope comes in a can with a brush
and is slightly more fluid than joint stick. The key to success with
joint stick or pipe dope is to apply it liberally and around all
sides of the male threaded fitting, so that you have even coverage
when you finally screw the fittings together. Some product will ooze
out as you tighten the fittings together, but that proves that you
have applied enough. If you use dope or stick, be sure it is a
non-petroleum-based material. Petroleum-based products will dissolve
plastic over time, creating leaks.
A hacksaw or a pipe cutter can be used for
cutting the pipes. Pipe cutters are adjustable wrench-like devices
that have cutting wheels and are made for cutting PVC or metal
pipes. You lock the device around the pipe and rotate it, constantly
tightening it as you go, until the pipe is cut. They provide the
straightest, cleanest cut of all. A hacksaw can do the work faster
if it has fresh blade attached to it.
Pool plumbing is prepared with plastic or
metal lengths of pipe and connection fittings that join those
lengths together. The pipe acts as the male which fits and is glued
into the female openings of these connection fittings.
Alternatively, connection is made by each side having threads,
joined by screwing them together. The plastic pipe used is PVC
(polyvinyl chloride) and it is manufactured in a variety of
different strengths depending on the intended use.
To help identify the relative strength of PVC,
it is labeled by a schedule number; the higher the number, the
heavier and stronger the pipe. Pool plumbing is done with PVC
PVC is designed to carry unheated water (under
100 degrees F). CPVC is formulated to withstand higher temperatures
for connection close to a pool or spa heater.
All pipe is measured by its diameter,
expressed in inches. Typically pool plumbing is done with 1/2- or
2-inch pipe, referring to the interior diameter (the diameter of the
pipe that is in actual contact with the water). The exterior
diameter of the pipe is more related to the wall thickness depending
on the material.
All pipe is connected with fittings. Fittings
that allow connection of pipe along a straight run are called
couplings, at right angles are called 90-degree couplings or elbows,
45-degree angles, T fittings, and a variety of other formats. In the
case of PVC, such fittings are most often smooth-fitted and glued
together called slip fittings.
Some fittings are threaded (called threaded
fittings) with a standard plumbing thread size so they can be
screwed into comparable connecting fittings in pumps or other
plumbing parts. National Pipe Thread (NPT) standards are used in the
United States so different products of various materials by
different manufacturers will all work together. The NPT standard
includes a slight tapering between the male and female connections.
The importance of this is that because of this taper, it is easy to
over tighten plastic threaded fittings and crack them. Great
Britain, Europe, and Asia not only operate on metric measurements,
but also have their own unique thread standards. Fittings with male
(external) threads are called mip and fittings with female
(internal) threads are called fip. If one side of the fitting is mip
and one side is slip, you order it as mip by slip, and so on.
In most cases with pool and spa plumbing, the
long runs of pipe will be underground. Sometimes, however,
horizontal runs will be under a house or deck or over a slope where
support is needed. in this case, pipe should be supported every 6 to
8 feet, hung with plumber's tape to joists or supported with wooden
bracing. PVC does not require support on vertical runs because of
its stiffness, but common sense and local building codes might
require strapping it to walls or vertical beams to keep it from
shifting or falling over. Remember, the pipe becomes considerably
heavier when it is filled with water and might vibrate along with
The supplies and tools you need for PVC
plumbing are: Hacksaw with spare blades (coarse: 12-18 teeth per
inch); PVC glue and primer; Cleanup rags; Fine sandpaper; PTFE
tape or joint stick.
The concept of joining PVC pipe involves
welding the material together by using glue that actually melts the
plastic parts to each other. In truth, each joint will have an area
that is slightly tighter than the rest. In the tightest parts, this
welding actually occurs. In the remainder, the glue bonds to each
surface and itself becomes the bonding agent. Obviously the
strongest part of each joint is the welded portion; but in either
case, the key is to use enough glue to ensure total coverage of the
surfaces to be joined.
Following is the correct procedure for
plumbing with PVC:
- Cut and dry fit all joints and plumbing
planned. Dry fitting ensures the job is right before gluing. If
you need the fitting and pipe to line up exactly for alignment
with other parts, make a line on the fitting and pipe, with a
marker when dry fitting so you have a reference when you glue
- Lightly sand the pipe and inside the
fittings so they are free of burrs. The slightly rough surface
will also help the glue adhere better.
- Apply a preparation material, called
primer, to the areas to be joined before gluing. Some PVC glues
are solvent/glue combinations and no primer is required. In some
states, however, use of primer might be required by building
code, so check that before selecting an all-in-one product. If
you are using primer, apply it with the swab provided to both
the pipe and the inside of the fitting. Read and follow the
directions on the can.
- Before gluing, be ready to fit the
components together quickly because PVC glue sets up in 5 to 10
seconds. Apply glue to the pipe and inside of the fitting.
- Fit the pipe and fitting together,
duplicating your dry fit, and twist about a half turn to help
distribute the glue evenly, realigning the lines drawn on the
pipe and on the fitting. If using flexible PVC, because it is
made by coiling a thin piece of material and bonding it
together, do not twist it clockwise. This can make the material
swell and push the pipe out of the fitting.
- With rigid PVC, hold the joint together
about a minute to ensure a tight fit; about two minutes with
flex PVC. Although the joint will hold the required working
pressure in a few minutes, allow overnight drying before running
water through the pipe to be sure.
- Make all threaded connections first, so if
you crack one while tightening it can be easily removed. Then
glue the remaining joints to the threaded work.
- When cutting PVC pipe, hacksaw blades of 12
teeth per inch are best, particularly if the pipe is wet (as
when making an on-site repair). Finer blades will clog with
soggy, plastic particles and stop cutting. In all cases, the key
is a fresh, sharp blade. For the few pennies involved, change
blades in your saw frequently rather than hacking away with dull
blades-you'll notice the difference immediately.
- No matter how careful you are, you will
drip some glue on the area or yourself. Always carry a supply of
dry, clean rags to keep the work area clean of glue.
- Try to make as many free joints as possible
first. By that I mean the joints that do not require an exact
angle or which are not attached to equipment or existing
plumbing. The free joints are those that you can easily redo if
you make a mistake. Do the hard ones last-those that commit your
work to the equipment or existing plumbing and cannot be undone
without cutting out the entire thing and starting over.
- Use as much glue as you need to be sure
there is enough in the joint. It's easier to wipe off excess
glue than to discover that a small portion of the joint has no
glue and leaks.
- Flexible PVC is the same as rigid, but when
you insert the pipe into a fitting, hold it in place for a
minute or longer because flex PVC has a habit of backing out
somewhat, causing leaks.
- In cold weather, more time is required to
obtain a pressure-tight joint, so be patient and hold each joint
together longer before going on to the next.
- Bring extra fittings and pipe to each job
site. Bring extras of the types you expect to use, as well as
types you don't expect to use, because you just might need them.
Bring extra glue, sandpaper, and rags too.
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Copper plumbing is more difficult to install
and repair, and it has become extremely expensive in recent years,
so copper plumbing is quickly being replaced by PVC. Unlike PVC,
copper plumbing will corrode, especially in the presence of caustic
pool and spa chemicals moving at high speed and under pressure
through the pipes.
Copper was more recently still in use where
dissipation of heat was important, such as in plumbing directly
connected to the heater. Stainless steel heat risers and threaded
galvanized plumbing have replaced that function, making copper
plumbing for pools and spas obsolete. Copper is still widely present
in various older installations. Copper pipe and fittings look
similar to those made of PVC and come in similar sizes and fitting
Copper pipe is made in three thicknesses,
designated by the letters K (thick wall), L (medium), and M (thin).
Most pool plumbing is done with L (medium thickness) material.
The supplies and tools you need for copper
plumbing are: Hacksaw with spare blades (fine: 32 teeth per inch);
50/50 solid wire solder; Flux with application brush; Emery cloth or
fine steel wool; Butane torch.
Be sure to read the general plumbing
guidelines section and the one on PVC plumbing because some of the
commonsense methods apply to copper work as well.
Following is the correct procedure for
plumbing with copper:
- Clean pipe and fittings. Start by cutting
and dry fitting all intended connections, then clean the ends of
the pipe and inside the fittings with the emery cloth (or fine
steel wool), sanding until the copper is shiny and bright. Apply
a thin coating of flux to the pipe and inside the fitting with a
small, stiff brush, coating the entire area where you want
solder to make a connection.
- Fit the parts together and twist a half
turn to evenly and thoroughly distribute the flux. Heat the
joint with your torch, moving the flame back and forth and
around the joint area to distribute the heat evenly until the
flux starts to bubble. Be sure the entire joint is hot. A good
way to know is to keep touching the solder to the joint until it
melts. When it does, you have the right temperature.
- Touch the solder to the joint. Solder with
lead melts and flows more easily. Recently many states have
restricted the use of lead in solder, at least when soldering
plumbing that is used for drinking water, so it might not apply
to pool installations in your state. 50/50 (50 percent lead, 50
percent amalgams) works best, but if no-lead solder is used,
even more heat must be applied and maintained during the
soldering operation to ensure melting and even distribution.
Apply solder to the fitting while continuing to heat the joint,
about an inch behind the joint. Solder is drawn toward the heat.
The solder melts and enters the joint wherever there is flux,
drawn in by capillary action, forming a seal. Work around the
joint, making sure solder is drawn into the entire joint.
- Clean excess solder away with a damp cloth
before it cools; but be careful, the heat turns the moisture on
the rag to steam which burns you worse than grabbing the hot
pipe directly. Allow the work to cool.
Two last items relating to copper plumbing.
First, threaded fittings are handled like PVC threaded fittings (see
previous section) using pipe dope or PTFE tape to ensure leak-free
Second, another type of copper connection
fitting is the compression fitting. This fitting is used in small
diameter (1/4- to 1/2-inch) pipe, often inside the heater. The
compression nut is placed on the pipe followed by the compression
ring. The pipe is placed inside the opposing fitting and when the
nut is screwed onto that fitting, the compression ring tightens
around the pipe and seals it.
- Copper pipe is cut with a hacksaw like PVC.
Use fine blade for copper (at least 24 teeth per inch or
preferably 32) as it cuts faster with each stroke.
- When making several connections with
various fittings, sweat as many joints as possible while they
are not connected to the equipment (just like the free joints I
mentioned in the PVC section). This way, I can test each joint
as it is completed. Hopefully only one or two joints will then
have to be soldered in-place and trusted to the luck and skill
of the work. To check if the joint is leak free, hold the work
with one hand over one end of the pipe or fitting and blow hard
through the other open end. No air should escape through the
joint-if air doesn't leak, neither will water. When sweating a
joint attached to equipment or other in-place plumbing, the only
leak testing will be when the job is complete and the system is
checked with water.
- Solder will not seal if there is any
moisture. If you must solder where some water is weeping from a
pipe connected to equipment, stuff the line with bread to absorb
the water. When the system is turned on again, the force of the
water will break down the bread and allow it to be filtered or
- Most leaks in sweating are caused by
moisture, overheating the joint, and most of all, unclean pipes
- Unlike PVC, sweating can be undone if you
need to repair a bad job or take old work apart to perform new
installations or add-ons. Apply heat to the joint, just as in
sweating, until the solder melts and pull the joint apart. If
you intend to reuse the fittings or that part of the pipe,
carefully clean and sand the copper to a good shine before
- Read the directions on the torch, the can
of flux, and the spool of solder. Sometimes reading another
person's directions for performing the same task will make more
sense than mine. Don't worry, I won't be offended, as long as
your work doesn't leak. Also, labels can provide helpful hints
that make for better, quicker jobs.
- When supporting copper pipe to joists for
long horizontal runs, use plumber's tape every 6 to 8 feet as
with PVC, but wrap the pipe in that spot with insulating tape
first. If you fail to do this, the different metals (copper pipe
and galvanized plumber's tape) will cause electrolysis,
corrosion, and leaks.
Galvanized means iron pipe that has been
coated with zinc or other alloys to prevent corrosion. You will
encounter galvanized plumbing in some installations. It is inferior
to PVC and copper because it is heavier and more difficult to use.
Because the interior surface of the pipe is rougher, it takes, for
example, a 3/4-inch galvanized pipe to carry as much water (at the
same pressure) as a 1/2-inch copper or PVC pipe. The rough surface
also promotes calcium buildup inside the pipe.
Galvanized plumbing can only be joined by
threading the pipe ends and fittings and screwing them together.
There is no simple sweating or gluing method as with copper or PVC,
so exact lengths and threading must be accomplished. However, it
does make an easy heat dispersal pipe for plumbing directly to the
heater. As shown, you can use a threaded galvanized nipple to thread
directly into the heater and then continue with PVC beyond that,
also threaded directly to the galvanized nipple. As with threaded
PVC or copper, use plenty of PTFE tape or pipe dope and tighten
the connections adequately. If connecting threaded PVC to
galvanized, apply PTFE tape and join as discussed previously.
If connecting galvanized to copper, you must
use a special union called a dielectric fitting. Because of the
different properties of the two metals, if they are connected
directly, they will corrode each other through electrolysis. The
dielectric union connects the two metals while shielding each from
the other. You probably won't use many of these, so if you need one,
ask at your plumbing supply house for more details.
Sometimes in tight quarters or for temporary
connections you can use rubber connection fittings called mission
clamps, balloon fittings, or no-hub connectors. These fittings are
handy for connecting pipes of different sizes or types, clamping
directly onto the pipe or fitting without gluing, threading, or
sweating. The hazard is that these can leak, wear out, or fail under
extreme pressure as when there is a restriction in the system from
debris or a dirty filter.
Most building codes restrict the speed of flow
through pipes to prevent stripping, breakdown, and erosion of the
pipe material. Typically water may not move faster than 8 feet per
second through copper pipe, and 10 feet per second through PVC.
Suction pipes of any type are typically restricted to 8 feet per
Obviously the larger the pipe, the better.
There is less restriction and therefore less strain on all equipment
and plumbing. Use the largest diameter pipe and fittings you can for
Typically pool and spa equipment is already
built and plumbed for 11/2- or 2-inch plumbing, and while you can
adapt 2-inch pipe to a pump that is designed for 11/2inch fittings.
The considerations in all cases are:
Desired flow rate of water (measured in
gallons per minute), Length of plumbing runs, Number and angles of
connection fittings, Pump efficiency and capacity, and Equipment and
restrictions after the pump.
Advanced plumbing systems includes automated
valves, reverse-flow heating, solar heating, and the use of new
materials. Let us discuss some of the more common applications of
advanced plumbing and the maintenance of these systems.
The three-port valve is often used when a pool
and spa share one filter, heater and pump. In this situation, the
water is alternately diverted to the pool or spa. Spas use the
three-port valve to divert air bubbles and jet water to one side of
the spa or the other, or the combination of both. The design of
three-port valves is such that water flow from one direction and
divides it into a choice of two other directions or the other way
round. To understand it more clearly, picture a Y, for example, with
the water coming up the stem, then a diverter allows a choice
between one of two directions, or a combination thereof. Conversely,
the water flow might be coming from the top of the Y, from two
different sources, and the diverter decides which source will
continue down the stem or mixes some from each together.
Manufacturers have different valves based on
the same concept. And keeping these valves well lubricated is best
for it maintenance.
Since the three port valves are used when the
water is shared between the pool and spa, they are designed to take
water flow coming from one direction and divide it into a choice of
two other directions. They are like letter Y or T. A handle placed
on top of the valve turns the diverter 180 degrees in either
direction, directing the flow and mixture of water that passes
through the circulation system.
Several manufacturers make three-port valves,
in Noryl plastic (a type of PVC) or brass, but the concept is the
same with them all.
The suction line from the pool enters one arm
of the valve body; suction from the spa enters the other. The
diverter between the two arms determines which line is connected
with the stem, from which the water continues to the pump.
Conversely, when the water leaves the equipment, it passes through
another three-port valve. The water this time passes up the stem and
the diverter determines if the water flows to the arm plumbed into
the pool return or the one plumbed into the spa return. By setting
the diverter equally between the two, water from each side is mixed.
Our Parts Department Now
A valve with the diverter that is surrounded
by a custom-made gasket so that no water can bypass the intended
direction, is called a positive seal valve.
Some valves, have no such gaskets and, are
designed more like a shovel head than a barrel. These divert most of
the water in the desired direction with a lesser amount going in the
other direction. These are called non-positive valves.
The diverter is held in the valve by a cover
that screws to the housing with sheet metal screws, and is sealed
with an 0 ring to make it watertight.
Besides the four screw holes in the cover and
housing, there is a fifth hole in the cover. This is to ensure that
the cover lines up properly with the housing, because on the
underside of the cover are specially molded stops. A small screw on
top of the diverter hits these stops molded into the underside of
the cover. This allows the diverter to be turned only 180 degrees in
either direction, ensuring only one side opening.
This screw is removed when the valve is
motorized because the motors only rotate in one direction and are
already precise in stopping every half-turn. Small machine screws
hold the handle on the shaft. A hole in the center of the cover
allows a shaft from the diverter to attach to the handle for manual
operation of the valve. To make the shaft hole in the cover
watertight, two small O-rings slide on the shaft in a groove under
As there are simple parts involved, the three
port valves are very easy to handle.
Like any other PVC fitting, Noryl three-port
valves are glued directly to PVC pipe using regular PVC cement .
Avoid too much glue, as excess glue can spill onto the diverter.
Excess glue can dry into hard and sharp mass, which may create leak
when turning the diverter, there by cutting the gasket.
Brass valves are sweated onto copper pipe like
any other fitting. Remove the diverter when sweating so the heat
doesn't melt the gasket.
Lubrication is most important measure to take
when it comes to maintaining a three-port valve. The gasket must be
lubricated with pure silicone lubricant. Most other lubricants are
petroleum based and can dissolve the gasket and can create leaks.
Lubrication should be done when operation
feels stiff or at least every six months. This twice a year
lubrication is important , especially for motorized valves, because
the motor will strain against old, sticky gaskets until the diverter
and shaft break, or the motor burns out completely.
To repair a sticky valve from the diverter;
firstly disassemble the valve by unscrewing and removing the handle.
Then unscrew and remove the cover. Pull out the diverter. Replace
the broken diverter and also change the old gasket. Now apply the
lubricant liberally and reassemble. Check the diverter by twisting
it back and forth several times, there by lubricating the whole
Common problems with three-port valves are the
leaks. Before starting the repair works, check its location in
relation to the pool or spa water level. If it is below the water
level, first shut off both the suction and return lines for opening
the valve will flood the area. If installations are made below water
level, they are usually equipped with shutoff valves. You will need
to reprime the system after making repairs.
The valve will sometimes leak from under the
cover. Either the cover gasket is too compressed and needs
replacement or the cover is loose. The cover is attached to the
Noryl valve housing with sheet metal screws. If tightened too much,
the screw strips out the hole and you will be unable to tighten it.
The only remedy is to use a slightly larger or longer screw to get a
new grip on the plastic material of the housing. Be sure to use
stainless steel screws or the screw will rust and break down,
causing a new leak. If new screws have already been used and there
is not enough material left in the housing for the screw to grip,
you must replace the housing.
Leaks also occur where the shaft comes through
the cover. Remove the handle and cover and replace the two small
O-rings. Apply some silicone lubricant to the shaft before
reassembly. This lubricates the operation of the valve, decreasing
friction that can wear out the O-rings. The lubricant also acts as a
Leaks can occur where the pipes join to the
housing ports. In this case, the only solution is replacing the
Leaks can also occur inside the valve with no
visible external evidence. Water is not completely diverted in the
intended direction, but slips past the diverter seal to the closed
side of the valve. The symptom will be a spa that drains or
overflows for no reason. The cause might be a diverter that is not
aligned precisely toward the intended port. Remove the diverter and
make sure the shaft has not separated or become loose from the
With a motorized unit, be sure the motor is
clean, free of rust, and able to turn its precise one-half turn each
time. The other and most usual cause, however, is that the diverter
gasket has worn out or become too compressed to stop all water from
getting past. Replace it. It takes very little deterioration or
compression to cause these bypass-type leaks. Again, lubricate the
gasket well before reassembly for smooth operation and because the
lubricant acts as a sealant.
Bypass leaks also result when the diverter
itself has shrunk or warped. This sometimes happens when the spa
water is very hot or the system ran dry and overheated. Such
shrinkage if difficult to see, and does not have to be extensive to
cause a bypass leak.
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When small motors are mounted on the valve in
place of the manual handle, for automatic or remote operation, makes
them motorized or automated three-port valves.
The pool or spa equipment are usually located
away from the pool and spa. Some builders place the manual valves
near the spa rather than in the equipment area for convenience. The
value of motorization is based on the concept so as to locate the
motor switch with the equipment and operate it with a remote control
unit. The remote might also have other functionalities like lights,
spa booster motors and blowers, or other optional accessories.
A manual valve can be motorized and the wiring
diagram are provided with each type of valve motor. To motorize an
existing valve, the handle and the screws, holding the cover in
place are removed. A mounting bracket is set on top of the cover and
slightly longer sheet metal screws, are used to refasten the bracket
and cover, to the housing. These longer screws are provided with the
motor bracket kit. The machine screws that normally hold the handle
in place are left on the shaft. The motor unit mounts on the
bracket, held in place by two screws, and the motor shaft slips over
the diverter's shaft. The two shafts are secured together by
tightening the screws of the diverter shaft. Wiring diagrams are
provided with each type of valve motor and they are designed to
operate on standard 110 volt, 220 volt, or from an automated system
that has been transformed to 12 or 24 volts.
The problems of the motorized valves are same
as that of manual valves.
As mentioned, if the valves are not properly
lubricated or become jammed with debris, the motor will continue to
try to rotate the valve, finally burning itself out.
If the motor has burned out, using an
electrical multimeter, verify that current is getting to the motor.
Obviously if there is no current, the problem is in the switch or
power supply and probably not the motor. If you are not familiar
with basic electricity, call an electrician to help you.
If current is present, remove the motor unit
from the valve and try to operate the system. if the motor rotates
the shaft normally, then the problem is a stuck valve and not a
burnt motor. Repair the valve as described in the previous section.
If the motor is burnt out, it can easily be
replaced without replacing the entire unit or valve.
Also check the screws for rust and for
becoming loose. For another problem that can occur with motorized
valves is that if the mounting bracket or screws holding the unit
together become loose, the unit will not align correctly with the
valve. So though the motor will rotate its 180 degrees, but it will
not fully rotate the valve diverter to match. The solution is to
tighten all hardware and replace any rusted screws.
Sometimes a system with far more valves and
plumbing can reverse the flow system. First thing is to observe the
normal operation and mark the pipes and valves with a marker. When
you are sure of the correct flow pattern that is, from the pool or
spa, through the equipment, and back to the pool or spa: simply turn
on the heater and observe it again.
If it is a reverse flow system, remove the
excess valve motors to disable the system. Don't try to leave the
units intact and simply disconnect the wiring. This might also
disconnect the heater on/off or pump switches that are associated
with the remote control system. It is easier to manually remove the
motors while leaving the valves in a normal circulation position,
clip off and cap the wiring to those motors, and leave the rest of
the unit as is.
When you remove a particular piece of
equipment that is plumbed into the system, you must cut out the
plumbing and replumb upon reinstallation. But concept of the union
is that when you need to repair or replace a pump, filter, or other
equipment you need only unscrew the plumbing and reinstall it. Union
allow you to easily remove and replace equipment without doing any
Unions, like other plumbing, are made of
plastic or metal in standard diameters and are adapted to plumbing
like any other component. In a typical plumbing union, a nut is
placed over the end of one pipe, then male and female fittings
called shoulders are plumbed onto each end of the pipes to be
joined. The joint is made by screwing the nut down on the male
fitting. PTFE tape or other sealants are not needed as the design
of the union prevents leaking.
Unions are made for direct adaptation to pool
and spa equipment, where the pipe with the nut and female shoulder
is male-threaded at its other end for direct attachment to the pump,
filter, or any other female threaded equipment. Then, only the male
shoulder need be added to the next pipe and the piece of equipment
can be screwed into place.
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Gate and ball valves systems are seen where
the equipment is installed below the water level of the pool. They
are designed to shut off the flow of water in a pipe and are used to
isolate equipment or regulate water flow. It prevents flooding when
you open or remove a piece of equipment or plumbing for repairs.
Before the development of three-port valves, shutoff valves were
used on each pipe to manually determine water flow from and to pools
and spas, in the older plumbing system.
The gate valve and the ball valve are the two
types of shutoff valves. The gate valve has a disc-shaped gate
inside a housing that screws into place across the diameter of the
pipe, shutting off water flow. A variation of this is the slide
valve, where a simple guillotine-like plate is pushed into place
across the diameter of the pipe.
The other design is the ball valve, where the
valve housing contains a ball with a hole in it of similar diameter
as the pipe. A handle on the valve turns the ball so the hole aligns
with the pipe, allowing water flow, or aligns across the pipe,
blocking flow. In each of these designs, flow can be controlled by
degree as well as total on or total off.
The gate valve is operated by a handle that
drives a worm screw-style shaft inside a threaded gate. If the gate
sticks from obstruction or rust and too much force is applied to the
handle, the screw threads will strip out, making the valve useless.
The valve cap, also called the bonnet can be unscrewed and the drive
gear and gate can be removed and repaired or replaced without
removing the entire valve housing. Most plumbing supply houses sell
these replacement guts, but the parts from one manufacturer are not
interchangeable with another.
The packing gland prevents leaks where the
shaft enters the valve body. If leaks occur here, the packing
material can be replaced by unscrewing the cap nut, removing the old
twine and rewinding new twine. Sometimes just tightening the cap nut
will stop the leak, but it also tightens the packing material on the
shaft, making it more difficult to turn. Plastic gate and ball
valves use O-rings to prevent leaks in this location.
The purpose of the check valve is to check the
direction of water flow. The check valves have multipurpose uses,
and the common ones are listed below.
To keep hot water from flowing back into the
filter they are used in heater plumbing.
They are used in the spa air blower plumbing.
To check the flow of water and make sure that only air is blown into
the pipe and into the blower machinery.
To keep the flow of caustic chemicals moving
in the desired direction, with chlorinators.
When the pump is located above the pool water
level, check valves are placed in front to keep water from flowing
back into the pool when the pump is turned off.
There are two types of check valves, a flapper
gate type and a spring-loaded gate type. The flapper style opens or
closes with water flow, while the spring-loaded style are designed
to respond to certain water pressure. Depending on the strength of
the spring, it might require one, two, or more pounds of pressure
before the spring-loaded gate opens. As with other valves, check
valves are made of plastic or metal in standard plumbing sizes and
are plumbed in place with standard glue, thread, or sweat methods.
The flapper-style valve is simple in design
and working. It must be installed with the hinge of the flapper on
top. If it is installed on the bottom, gravity will pull the flapper
open all the time. Sometimes with metal flapper check valves, as the
flapper opens and closes you can hear them chatter, particularly if
there is air in the system. This is not a malfunction or a problem
of the valve. With the metal flapper, the gate may come off the
hinge due to rusting. The valve then must be replaced.
All check valves clog easily with debris,
remaining permanently open or permanently closed. Because of the
extra parts inside a spring-loaded check valve, they are more prone
to failure from any debris allowed in the line. If the valve is
threaded or installed with unions, it is easy to remove it, clear
the obstruction, and reinstall it. Another solution is to use the
90-degree check valve. This valve allows you to unscrew the cap,
remove the spring and gate, remove any obstruction, and reassemble.
Be careful not to over tighten the cap-they
crack easily on older models; newer models are made with beefier
caps to prevent this problem. These units have an O-ring in the cap
to prevent leaks. It is wise to clean these out every few months and
lubricate the gate, using silicone lubricant only.
Plumbing for solar heating is no different
from other pool and spa plumbing. It is located between the filter
and the heater, so water going to the solar panels is free of debris
and is available for solar heating.
A thermostat on the solar panel determines the
water temperature. The water coming out of the filter goes to a
three-port motorized valve which sends the water to the solar panels
for heating and returns it to the plumbing that enters the heater.
The heater thermostat senses the temperature of this solar heated
water and if it is still not as hot as desired, the heater will come
on to heat it further before returning it to the pool.
Therefore a main component of solar heat
plumbing is the three-port valve that either sends the water from
the filter directly to the heater or sends it first to the solar
panels and then the heater. A check valve is installed on the pipe
that returns water from the solar panel to the heater to prevent
water from entering this return line when the solar panels are not
in use. This might instead be another three-port valve that performs
the same function as the check valve but also ensures that when not
in use, the solar panels will not drain out. This might not be
important where solar panels are installed at or below the water
level of the equipment and pool, but most installations of panels
are on rooftops, high above the water level.
A solar heating package from your pool supply
house includes panels, plumbing, controls, and instructions. You
should hire a licensed carpenter, to help with the installation and
support of the panels and also complete the plumbing into the
The existing pump will probably be adequate
for circulation when adding solar equipment, because the gravity and
siphon effect balances the additional pressure the pump experiences
trying to push the water up to the panels. Therefore, the height of
the panels above the water has no effect on the pump's ability to
However you have to calculate the effect of
the length of pipe and fittings as with any plumbing installation.
When planning an installation, the pipes to and from the panels
should be insulated so heat is not lost along the way.
Once installed, the solar heating system
should be checked for leaks. Leaks can easily occur because of the
extremes of hot and cold temperatures that cause the panel materials
to expand and contract. Leak repair depends on the type of material
in the panel or plumbing, and each manufacturer makes leak repair
kits with instructions. The plumbing to and from the panels can be
repaired as needed using the techniques outlined in the chapter on
Dirt prevents the panels from absorbing heat
and can cut efficiency by as much as 50 percent. Cleaning will solve
Panels can become clogged with scale from hard
pool water and chemicals. Poor circulation can result due to
clogging and disassembling the panels from each end and exposing the
pipes of the panel that actually carry the water, and reaming these
out with special brushes is the solution to it. Again, how you make
this repair depends on the maker of the panel and its style. The
maker should provide instructions and special tools for this
procedure. As with leak repair or cleaning of solar panels, reaming
is simple to perform using the right techniques and skills.
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The most simple and common method of replacing
evaporated water in the pool or spa is to turn on the hose. But this
can take from few minutes to long hours. This can make you to forget
to turn off the hose some time. To overcome this automated water
fill systems are available to do this job.
There are basically two kinds of automated
water fill systems and other systems with variations on those themes
are available. If the pool or spa was built with a water fill line
plumbed in place, the on/off anti-siphon valve can be replaced with
a mechanically timed valve. In this way, you can set the water to
run 1 to 60 minutes.
Instructions for removing the manual valve and
installing this timer valve are in the package with the valve and
are simple to follow. For this you must turn off the household main
water supply. This is probably the only pool or spa repair requiring
shut off of the household water supply.
First, locate the supply meter, usually in
front of or alongside the house, in the ground, mounted in a
concrete box. Inside the box you will see the meter with a gate
valve on the outflow side of the meter. Turn this off. If it is
stuck or rusted, there is a shutoff valve on the inflow side of the
meter, but not with a standard handle. This valve can be turned off
with a channel lock pliers or a small pipe wrench by gripping the
post of the valve and turning it so it lines up across the pipe.
A variation on the timer valve is a similar
unit calibrated by gallons rather than time. It screws onto a hose
bib, the hose is screwed onto the timer unit, the hose bib is turned
on, and the dial is set for the number of gallons you need. You
determine the gallons needed by calculating how many inches of water
are needed, and how many gallons are in those inches.
There are, however, some models available in
gardening supply shops that include solid-state components for
regularly scheduled timed water flow or preset volume flow. These
require batteries and careful setting and work well if you carefully
check and recheck your settings and change the batteries frequently
so the system doesn't fail.
The other type of water level control works
much like the float valve in your toilet. A float which opens and
closes a valve attached to a water supply line, is located at the
water level desired. When the level drops, the float drops, opening
the valve. As the level rises, the opposite happens. The float and
plumbing can be located in the skimmer, but is more often located in
a small separate reservoir tank, perhaps not even near the pool. The
tank must be set at the same level as the pool, so the water in it
imitates the water level of the pool. A pipe connects this tank with
the pool so the actual water and its level are the same in each.
Also, as the level drops, the water fills the pool through this
These units are reliable and can be adjusted
for water level by bending the arm on the float to the desired level
or by setting the elbow in the float arm accordingly. A set screw
loosens the elbow to allow adjustment. The small valve is threaded,
so if it rusts, clogs, or fails, it can be unscrewed and easily
Water level controls serve another valuable
purpose. As water evaporates, scale of minerals especially calcium
are formed on the tiles and artificial rocks. So the simplest method
is to keep a constant water level in the pool. As water evaporates
and leaves scale, fresh water is introduced to refill the pool to
cover the scale line.