15
FACTORY INSTALLED FEATURES
A number of factory installed options are available on the GZ
Series of Heat Pumps. The following details the purpose, function
and components of each option.
Heat Recovery Package (HRP)
(optional)
The heat recovery package is a factory installed option on GZ
series heat pumps. The HRP can be used to heat potable water
during unit operation using waste heat from the compressor
discharge gas. In some cases the HRP can provide most or all of
the hot water requirements for a typical home.
The HRP consists of three major components:
1. Double wall, vented refrigerant to water heat exchanger
2. Circulating pump
3. Control circuit
The heat exchanger is rated for use with potable water and is
acceptable for use as a domestic water heating device in most
building codes.
The pump circulates water between the domestic hot water tank
and HRP heat exchanger in the Heat Pump. The control circuit
ensures that the HRP only operates when there is available heat
from the compressor and when the water is within a safe
temperature range of below 140
_
F. When the heat pump
compressor operates, the HRP will monitor the temperature of the
discharge gas from the compressor. Once discharge gas is hot
enough to provide useful heat to the domestic water tank, the
circulating pump will be enabled, drawing water from the tank,
through the HRP heat exchanger and then depositing the heated
water back into the tank.
If the water temperature reaches 140
_
F, the circulating pump is
disabled to prevent over heating of the domestic water. The HRP is
provided with an on/off switch in case the end user desires that the
HRP be inactivated (typically during the winter months when
space heating is most important).
The circulating pump is enabled when compressor discharge
temperature reaches 120
_
F (48.9
_
C).
The circulating pump is disabled if an overload condition exists
(over 1.35 amps).
CAUTION
!
UNIT DAMAGE AND/OR OPERATION HAZARD
Failure to follow this caution may result in unit damage
and/or improper equipment operation.
If heat recovery unit is installed in an area where freezing
may occur, the unit must be drained during winter months
to prevent heat exchanger damage. Heat exchanger
ruptures that occur due to freezing will void the heat
recovery package warranty along with the heat pump
warranty.
CAUTION
!
UNIT DAMAGE AND/OR OPERATION HAZARD
Failure to follow this caution may result in unit damage
and/or improper equipment operation.
Do not apply additional controlled devices to the control
circuit power supply without consulting the factory. Doing
so may void equipment warranties.
FIELD INSTALLED ACCESSORIES
Liquid Line Solenoid Accessory
Experience and good design practice dictate 75 feet as the
maximum practical length for interconnecting refrigerant lines in
split system heat pumps without special considerations. Beyond 75
feet, system losses become substantial and the total refrigerant
charge required can compromise the reliability and design life of
the equipment.
Local codes or installation may suggest a liquid line solenoid,
installation of long line solenoid should adhere to valve installation
instructions.
Accessory Liquid Solenoid with Communicating System Wall
Control: When using the Wall Control, the liquid--line solenoid
output is provided at the Y1 connection. Connect the solenoid as
shown in Fig. 19. This is a 24VAC output that is energized
whenever the compressor is energized. In compressor OFF mode,
it closes to prevent refrigerant migration into the unit through the
liquid--line.
Systems
with
Accessory
Liquid
Solenoid
Using
a
Non--Communicating Thermostat:
The liquid solenoid is connected to the Y1 and C terminal
connections (see Fig. 19) and assumes that both Y2 and Y1 are
energized by the thermostat during call for high stage operation.
In compressor OFF mode, the liquid solenoid closes to prevent
refrigerant migration into the unit through the liquid--line. The
terminal connections for Y1 and C will have LLS and the stat wires
sharing the same connection points.
C W/Y
LLS & Water
Solenoid
NOTE
: Optional wiring if wiring kit #4129 is not used.
A150167
Fig. 19 -- LLS and Water Solenoid Connections
