Remote HWG
Rev.: Februrary 10, 2016
8Geothermal Heat Pump Systems
Hot Water Generator Module - Domestic Water Installation
The heat pump, water piping, HWG, and hot water tank
should be located where the ambient temperature does
not fall below 50°F [10°C]. Keep water piping lengths at a
minimum. DO NOT use a one way length greater than 50 ft.
(one way) [15 m].
All installations must be in accordance with local codes. The
installer is responsible for knowing the local requirements,
and for performing the installation accordingly. DO NOT
connect the pump wiring until “Initial Start-Up” section,
below. Powering the pump before all installation steps are
completed may damage the pump.
Water Tank Preparation
1. Turn o power or fuel supply to the hot water tank.
2. Connect a hose to the drain valve on the water tank.
3. Shut o the cold water supply to the water tank.
4. Open the drain valve and open the pressure relief valve
or a hot water faucet to drain tank.
5. When using an existing tank, it should be ushed with
cold water after it is drained until the water leaving the
drain hose is clear and free of sediment.
6. Close all valves and remove the drain hose.
7. Install HWG water piping.
HWG Water Piping
1. Using at least 5/8” [16mm] O.D. copper, route and install
the water piping and valves as shown in Figures 1 or 2.
Install an approved anti-scald valve if the 150°F HWG
setpoint is or will be selected. An appropriate method
must be employed to purge air from the HWG piping.
This may be accomplished by ushing water through the
HWG (as In Figures 1 and 2) or by Installing an air vent at
the high point of the HWG piping system.
2. Insulate all HWG water piping with no less than 3/8”
[10mm] wall closed cell insulation.
3. Open both shut o valves and make sure the tank drain
valve is closed.
Water Tank Rell
1. Close valve #4. Ensure that the HWG valves (valves #2
and #3) are open. Open the cold water supply (valve #1)
to ll the tank through the HWG piping. This will purge air
from the HWG piping.
2. Open a hot water faucet to vent air from the system until
water ows from faucet; turn o faucet. Open valve #4.
3.
Depress the hot water tank pressure relief valve handle to
ensure that there is no air remaining in the tank.
4. Inspect all work for leaks.
5.
Before restoring power or fuel supply to the water heater,
� WARNING! �
adjust the temperature setting on the tank thermostat(s)
to insure maximum utilization of the heat available from
the refrigeration system and conserve the most energy.
On tanks with both upper and lower elements and
thermostats, the lower element should be turned down
to 100°F [38°C] or the lowest setting; the upper element
should be adjusted to 120-130°F [49-54°C]. Depending
upon the specic needs of the customer, you may want
to adjust the upper element dierently. On tanks with a
single thermostat, a preheat tank should be used (Fig 2).
6. Replace access cover(s) and restore power or
fuel supply.
Initial Start-Up
1. Make sure all valves in the HWG water circuit are fully
open.
2. Make electrical connections (power and low voltage)
as shown on the HWG wiring diagram. Example wiring
diagrams and an electrical data table are included in this
document (See Figures 5-8).
3. Turn the heat pump power and remote HWG power “o”
and switch dip switch SW12 on the HWG controller to the
“o” (enabled) position to activate the HWG.
4. The HWG pump should not run if the compressor is not
running.
5. The temperature dierence between the water entering
and leaving the HWG should be approximately 5-10 °F
[3-6 °C].
6. Allow the unit to operate for 20 to 30 minutes insure that
it is functioning properly.
7. Always turn dip switch SW12 on the HWG controller to
the “on” (disabled) position to deactivate the HWG when
servicing the outdoor compressor section.
Warning! Use extreme caution when working around
the microprocessor control as it contains line voltage
connections that presents a shock hazard that can
cause severe injury or death!
HWG Water Piping Size and Length
Unit
Nominal
Tonnage
Nominal
HWG Flow
(gpm)
1/2" Copper
(max length*)
3/4" Copper
(max length*)
1.5 0.6 50 -
2.0 0.8 50 -
2.5 1.0 50 -
3.0 1.2 50 -
3.5 1.4 50 -
4.0 1.6 45 50
5.0 2.0 25 50
6.0 2.4 10 50
*Maximum length is equivalent length (in feet) one way of type L
copper.
