Intertek A/GPD1424 Series, Installation Instructions Manual

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14
CONDENSATE DRAIN
C
ONDENSATE
D
RAIN
C
ONNECTION
A 3/4” NPT drain connection is supplied for condensate piping. An
external trap must be installed for proper condensate drainage.
NORMAL SEQUENCES OF OPERATION
HEAT PUMP OPERATION
O
UTDOOR
T
HERMOSTAT
For optimal performance, a dual fuel thermostat with an outdoor tem-
perature sensor should be used. TSTATGTS3275 (Emerson Dual Fuel thermostat) with TSTATTSORS (outdoor temperature sensor) is
recommended.
This will allow the installer to control when the unit switches from heat pump to gas heat based on a set point entered into the
thermostat. It is recommended to set the thermostat between 35° - 45°F, depending on regional climate and energy rates.
O
PTIONAL
O
UTDOOR
T
HERMOSTAT
(OTDFPKG-01)
The outdoor thermostat is an optional accessory that can be set from 0 - 45°F and is set inside a “birdhouse” enclosure. This
enclosure will be mounted near the blower access panel. The dimples and knock-out are located on the corner posts, providing
ease of installation. Once the thermostat closes, a 24 volt signal is sent to the W1 terminal instead of the Y terminal and the heating
cycle will change from Heat Pump to Gas heating. It is recommended to set the thermostat between 35-45°F depending on regional
climate and energy rates.
H
EATING
C
YCLE
(H
EAT
P
UMP
)
The heat pump operates in the heating cycle by redirecting refrigerant flow through the refrigerant circuit external to the
compressor. This is accomplished through the reversing valve. Hot discharge vapor from the compressor is directed to the indoor
coil (evaporator on the cooling cycle) where the heat is removed, and the vapor condenses to liquid. It then goes through the
expansion device to the outdoor coil (condenser on the cooling cycle) where the liquid is evaporated, and the vapor goes to the
compressor.
When the solenoid valve coil is energizing for cooling, the piston in the reversing valve to the low pressure (high pressure) reverse
positions in the reversing valve. In addition to a reversing valve, a heat pump is equipped with an expansion device for the indoor
coil, and similar equipment for the outdoor coil is provided with a defrost control system.
H
EATING
C
YCLE
(N
ATURAL
G
AS
/ LP)
1. The Dual Fuel unit will operate in gas heat mode when the thermostat calls for a W-1 or W-2 signal. If outdoor thermostat is
installed, the unit will operate in gas heat when ambient is below set point or the unit receives call for low or high stage gas
heat.
2. Induced draft blower energizes for 15-second pre-purge.
3. A 7-second trial for ignition begins by energizing the low and high stages of the gas valve along with this spark ignition.
NOTE: The igniter produces a very intense electrical spark that ignites the gas.
4. Main burners light and control detects presence of flame.
5. If the call is for low stage heat, the induced draft blower switches from high to low speed and the gas valve from high to low
stage within 5 seconds after the main burners light. If call is for high stage heat, induced draft blower remains at high speed
and high stage gas valve remains open.
NOTE: If a W2 is not used, the control will step to low stage after the main burners light and remain at low stage for 5 or
10 minutes, depending on jumper position. If the jumper is set to none, you will never get a call for high stage heat.
If the
call for HEAT remains after the transition delay time expires, the control will transition from low stage to high stage.
6. The 30-second HEAT FAN ON delay time begins after the main burners light.
7. The unit delivers heat to the conditioned space until the thermostat is satisfied.
8. Gas valve(s) de-energizes. The induced draft blower continues operation for a 30-second post-purge.
NOTE: Induced draft blower remains at low speed (or switches from high to low if operating at high stage heat) for the 30-
second post purge.
9. Ignition control begins timing the HEAT FAN OFF delay. There is an adjustable HEAT FAN OFF delay of approximately 90/120/
150/180 seconds (factory set at 150). If the unit is operating at high stage when the call for heat is removed, the blower will
operate for 30 seconds at high heat speed then switch to low heat speed for the remainder of the selected HEAT FAN OFF
delay.
NOTE: After the HEAT FAN OFF delay time has elapsed, the blower will de-energize. This allows any additional heat in the heat
exchanger to be transferred to the conditioned space.
DRAIN
CONNECTION
UNIT 2" MINIMUM
FLEXIBLE
TUBING-HOSE
OR PIPE
3" MINIMUM
A POSITIVE LIQUID
SEAL IS REQUIRED
Drain Connection