Unit installation

22
Turn the adjustment
clockwise and the
switch will require
"more" pressure rise
or drop to activate
and deactivate the
heater.
Turn the adjustment
counter clockwise
and the switch will
require "less" pres-
sure rise or drop to
activate and deacti-
vate the heater.
The water pressure switch is preset at the factory and
should only be adjusted slightly by one to two turns
maximum, in either direction. Adjust only when the
heater does not shut off with the water circulation pump.
WATER PRESSURE SWITCH CHECK
The water pressure switch is preset at the factory and should only be adjusted "if needed".
The water pressure switch is designed to shut the heater off when the water circulation pump shuts off. The water
pressure switch will keep the unit from running when there is no water flow. The water pressure switch has a 1 to
5 psi pressure range on water pressure rise or fall.
After you have plumbed and wired the heater, you should check to see if the heater will shut off when the circu-
lation pump shuts off. Also, test run other pool equipment (automatic pool vacuums, spas, solar panels, etc.), that
may restrict the water flow. If the heater stops running when these items are operating, you may have to adjust the
water pressure switch to compensate for flow restriction. The unit will suffer severe damage if it operates
without enough water running through the heat exchanger. If the system will not work due to low or fluctuating
water flow with the above mentioned items, you may require another optional, external water "FLOW" switch
(part# 888-032) OR a special use pressure switch (part# 408). A "flow" type switch can be used in place of the
existing water pressure switch inside the unit.
Remove Main
Compressor
Access Cover
Water Pressure
Switch Location
(Inlet Pipe)
Compressor
If the heater does not shut off when the circulation pump
does, or the heater cycles off and on, there may be a problem
in the filtering system or other equipment creating back pres-
sure on the system. Items such as solar panels, units in-
stalled above or below water elevation or suction leaks caus-
ing water to back siphon through the unit, may keep the
pressure switch engaged. Determine what can be done to
improve water flow to accommodate the addition of the new
heater.
NOTE: Be careful not to turn the adjustment
knob too far counterclockwise or the adjust-
ment knob and internal spring may come apart.
CAUTION
!