™ Solar Pool Heating System -- Installation & User Manual
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If the pump height is substantial and/or you have more than one return outlet to your pool, it may be that your
pump cannot positive pressurize the vacuum release valve. In this case you will get undesirable constant bubbling in
the outlet to the pool as the vacuum release valve is at negative pressure and is drawing in air. If this happens you
will need to install the down draft/brake PVC ball valve (16) on the return line (see plumbing diagrams) and carry out
the following procedure:
Start the system and wait for it to settle.
1) Constrict flow in the return line using the ball valve brake (16, see plumbing diagrams) lever handle by a
2) If after some time the air bubbling continues, constrict flow by another small increment.
3) If air bubbles stop reliably at this point, then the vacuum valve is now at the required positive pressure, the
pressure gauge should read a value near the head pressure (vertical distance from vacuum release and
pressure gauge) + a few kPa’s, this is ideal.
4) Leave the ball valve brake at this setting/constriction permanently (remove handle).
5) If the required constriction is greater than 50% you will need a stronger pump.
The following procedure for a manual system need be carried out only once during installation.
1) Open the three way ball valve (9, see plumbing diagrams) using the lever handle by a small increment.
2) Wait to see if there is sufficient flow and back pressure to create positive pressure at the vacuum valve (7).
3) If after some time air bubbling is still present in the return line, open the three way valve (9 see plumbing
diagrams) by another small increment.
4) If air bubbles stop reliably at this point, then the vacuum valve is now at the required positive pressure.
5) Fix in place a back stop on the ball valve lever handle at this travel point, as this will be your maximum
opening point for your three way valve when turning the heating system on again.
For an over-sized solar pump (13, see plumbing diagrams) we recommend the following procedure, carried out only
once during installation, to limit pressures inside the panels.
Over-sized pumps and flow rates could potentially limit the lifetime of your collectors due to
pressure working. Note, the return line to the pool MUST be unconstricted, with an
appropriate number of pool outlets so as not to create significant back pressure.
Use the below procedure for solving air bubbling issues, DO NOT remove or drop the
level of the vacuum release valve or increase pump strength. The vacuum release valve
MUST be mounted as specified to ensure collectors are not pressure worked.