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16
Installation and User’s Guide
Water Pressure Switch Adjustment
CAUTION
—
The water pressure switch should be adjusted to turn the heater off when the pump is off. Setting the switch
to close at too low of a flow can damage the appliance. Adjust the switch to turn the heater off, not on.
The pressure switch is preset at the factory for activation at 1.5 psi [10 kPa]. This factory setting works for most basic
installations as shown previously on
pages 7, 9-10
in this manual. Only adjust the water pressure switch if the heat pump
does not operate
when the proper flow is applied to unit
or if the heat pump does not shut off when the filter pump is off.
Occasionally, unusual plumbing configurations or necessary restrictions in the plumbing may cause pressure sensing
problems. In these rare situations, the plumbing system configuration may require adjustment of the water pressure switch.
Adjustment of the pressure switch may be necessary if any part of the filter system piping is 3 feet [0.91 m] or more above the
top of the heat pump.
In general, if the heat pump is installed more than 6 feet [1.83 m] below the pool surface, an external water flow switch must be
added to the plumbing system.
On some installations, the piping from the heat pump to the pool is very short. The back pressure could be too low to trigger the
pressure switch. If this happens, it may be necessary to install a directional fitting or elbows where the return line enters the pool.
This will increase back pressure enough for the heat pump to operate properly. If this configuration is necessary, be sure to check
that the system flow is above the minimum requirement of 30 gpm (110 lpm) after the direction fitting or elbow has been installed.
Make sure the pool filter is clean before making any pressure switch adjustment: A dirty filter will restrict the water flow and
the pressure switch cannot be adjusted properly.
To adjust the pressure switch:
The following adjustment is for installations where the heat pump is
below
pool water level.
1.
Be sure that all valves in the system are set to allow water flow through the heat pump. Start the filter pump.
2.
Set the heat pump temperature above the actual temperature to call for heat. Turn the heat Pump
ON
.
3.
Once the heat pump is running, turn off the filter pump. The heat pump should turn off immediately.
4.
If the heat pump continues to operate when the filter pump is off, then the water pressure switch needs to be adjusted.
5.
Remove the heat pump’s left front panel and remove remaining right front panel. The water pressure switch is located in
the water plumbing in the lower right corner of the heat pump.
6.
Slowly rotate the adjustment wheel on the water pressure switch in a
clockwise
direction until the the
“LOW WATER
FLOW”
Alarm shows on the LCD, the Red Service LED turns
ON
, and the heat pump stops.
7.
Check the setting of the water pressure switch by starting and stopping the filter pump and checking the control panel
and operation of the heater between each flow change.
8.
If the water pressure switch cannot be adjusted to accommodate the conditions listed above, an external flow switch must
be added to the plumbing system to ensure that the heat pump will not operate without the proper flow through the heat
exchanger.
The following adjustment is for installations where the heat pump is
above
pool water level.
1.
Be sure that all valves in the system are set to allow water flow through the heat pump. Start the filter pump.
2.
Set the heat pump temperature above the actual temperature to call for heat. Turn the heat Pump
ON
.
3.
If the LCD shows a “
LOW WATER FLOW
” Alarm and Red Service LED is present then the water pressure switch needs
to be adjusted.
4.
Remove the heat pump’s left front panel and remove remaining right front panel. The water pressure switch is located in
the water plumbing in the lower right corner of the heat pump.
5.
Slowly rotate the adjustment wheel on the water pressure switch in a
counterclockwise
direction until the “
LOW WATER
FLOW
” Alarm and Red Service LED vanish, time delay countdown will start.
6.
Once the heat pump is running, turn off the filter pump. The heat pump should turn off immediately.
7.
If the heat pump continues to operate when the filter pump is off, turn the adjustment wheel on the water pressure switch
in a
clockwise
direction until the “
LOW WATER FLOW
” Alarm shows on the LCD, the Red Service LED turns
ON
, and
the heat pump stops.
8.
Check the setting of the water pressure switch by starting and stopping the filter pump and checking the control panel
and operation of the heater between each flow change.
9.
If the water pressure switch cannot be adjusted to accommodate the conditions listed above, an external flow switch must
be added to the plumbing system to ensure that the heat pump will not operate without the proper flow through the heat
exchanger.