Although PVC pipe is generally white, black is also
available but may be difficult to find locally. If for
aesthetics black pipe is desired, it can always be
painted black. Before painting, the PVC pipe must be
wiped with cleaner to remove the glossy surface
coating. This will ensure that the paint will not flake
off prematurely.
MANUAL SYSTEMS
The manual control is with a non-positively sealed
three-way valve. Water flows continuously through
the solar collectors when the filter pump is on, but can
be diverted manually by the homeowner if the pool
becomes too warm or during extended cloudy
weather. During a thread of freezing conditions it can
also be diverted, by first shutting off the pool pump,
allowing the collectors to drain, diverting the three-
way manual valve to the “bypass collector” position
and shutting the isolation valves on the collector freed
and return lines. A lower end cap on the collectors or
any of the connecting hoses can be removed to make
sure there is no standing water in the panels. The filter
pump can then be re-started to allow for normal pool
filtration.
During normal operation of the system when the
three-way valve is in the ‘bypass collector’ position
all the water in the panels should drain back through
the three-way valve (non-positively sealed) when the
filter pump shuts off. An alternate way to protect
against sudden freezes can be accomplished by
running a bypass line (1/8”-14”) between the collector
feed and return line above the isolation valves. It is
possible that a small amount of water may be present
in the collectors when a non-positively sealed three-
way valve is used and the filter pump is on. If a
positively sealed three-way valve is used, a bypass
line as mentioned above is mandatory to allow for
panel drainage.
Automatic Control Systems
The performance of a solar pool heating system can
be improved with the use of an electronic control and
motorized three-way valve. The control activates the
motorized valve and either sends water through
collectors for heating or automatically bypasses the
collectors when the pool is warm enough of
insufficient sunlight is available. Refer to the
manufacturer’s instructions included with the
automatic equipment you use.
Other Equipment
Some pools employ an automatic pool cleaner. This
should be plumbed before the control valve to assure
positive flow to the cleaner at all times. If the pool
uses an automatic chlorinator, this should be plumbed
after the outlet tee on the return to the pool.
Supplemental Gas, Oil-Fired, or Electric Heaters
It is desirable to pipe the stand-by heater in a bypass
loop. Refer to the System Diagram Figure 12. Fuel-
fired heaters often create a large pressure drop. By
placing the heater in a by-pass loop, pump size, and
electrical energy requirements may be reduced.
SECTION 3: SYSTEM START-UP, CHECK-
OUT, AND MAINTENANCE
System Start-up and Check-out for Automatic
Systems
To check out the system for proper operation turn on
the filter system. Set the temperature control to its
highest level. Switch the control to the “flow through
collector” mode. The “flow through collector” light
should come on. The three-way valve will then be
sending water through the collectors, and air will be
purged out of the collectors into the pool return line
for several minutes, and should then clear. The panels
should feel uniformly cool to the touch. Switch the
control to the “bypass collector” mode. The
corresponding light will go on and the three-way
valve will be sending water directly back to the pool,
bypassing the solar panels. After about 5-10 minutes,
feel the solar panels again. They should have begun to
warm up. Now switch back to the automatic mode. If
the sun is still shining on the solar collectors, the
“flow through collector” light should come on again.
Slide the temperature control down ward, and when
you reach the actual temperature of the pool water,
the light will turn off. The flow bypass collector light
will go on again. Slide the temperature control to
maximum. The flow through collector light will go
back on. For more detailed information on the system
startup,
trouble
shooting
and
valve/control
installation, follow the manufacturers’ instructions
included with the automatic control system.
Flow Rate Test and Adjustment
With the system running and the sun shining, all
collectors of the system should be uniformly cool to
the touch, and the system will be operating at
optimum performance. If the system has been
installed according to these instructions, and the
