ICP CHS180, Инструкция по установке, запуску и обслуживанию

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Split System Heat Pumps Installation Instructions
14
Table 4 - Refrigerant Charge
Refrigerant Type R--22
Operating Charge (lb. oz.)* 37 -- 0
*The charge amount is related to a length of 25ft. used in
liquid and suction lines. Note: Add or remove the
refrigerant charge (.083lb/ft) when liquid and suction lines
have different lengths than 25ft.
FINAL CHECKS -- Ensure all safety controls are operating,
control panel covers are on, and the service panels are in
place.
Compressor crankcase heater must be on for 24 hours
before start--up. To energize the crankcase heater, set the
space thermostat above the ambient temperature so there
is no demand for cooling. Close the field disconnect.
The crankcase heater is now energized.
After the heater has been on for 24 hours, the unit can be
started. If no time has elapsed since the preliminary charge
step was completed, it is unnecessary to wait the 24--hour
period.
START UNIT -- Close the field disconnect and set the
Space thermostats above ambient temperature so that
there is no demand for cooling. Only the crankcase heaters
will be energized.
Place thermostat selector switch at COOL and set space
set point below ambient temperature so that a call for
cooling is ensured. If compressor does not start, set
thermostat lower.
CHECK HEATING CYCLE OPERATION -- Place
thermostat selector switch at HEAT and reset the space set
point above ambient temperature so that a call for heating
is ensured. Compressor will start. Observe system
operation.
Operating Sequence
HEATING -- Place thermostat selector at HEAT and set
temperature selector above room ambient.
COOLING -- Place thermostat selector at COOL and set
temperature selector below room ambient.
When thermostat calls for unit operation (either heating or
cooling), the indoor--fan motor starts immediately. The
outdoor--fan motors and compressor start within 3 seconds
to 5 minutes depending on when unit was last shut off by
thermostat, because unit contains a compressor time
delay circuit. When first--stage cooling is required,
thermostat (TC1) closes, causing the heat pump to start
with an unloaded compressor. When TC2 closes,
demanding additional cooling, the compressor loads to full
load operation.
During heating, compressor is always fully loaded. When
TH1 demands first--stage heating, the heat pump starts
within 3 seconds to 5 minutes depending on when unit was
last shut off by thermostat, because unit contains a
compressor time delay circuit. (The defrost board has
speed terminals to shorten this cycle.) When TH2 of the
thermostat closes, auxiliary heat supply (electric strip heat)
is energized in 1 or 2 stages depending on number of
stages available and whether outdoor thermostats are
closed.
Defrost Cycle
Defrost is achieved by reversal from heating to cooling
cycle and deenergization of outdoor--fan motors, allowing
hot refrigerant gas to defrost outdoor coil. Defrost is
achieved with a timer set to initiate defrost every 30, 50, or
90 minutes (factory set at 30 minutes).
Defrost is initiated when refrigerant temperature leaving
the outdoor coil is measured below 27 F (2.8 C), (typically
when the outdoor ambient temperature is below 45 F [7.2
C] as sensed by the defrost thermostat [DFT]).
Defrost is terminated when: The refrigerant temperature
rises to 65 F (18.3 C) (80 F [26.7 C] for CHS180) at the DFT
location on the liquid line; or the refrigerant pressure rises
to 280 psig (1931 kPag) at the HPS2 location on the liquid
line; or the defrost timer completes the 10--minute cycle.
Air Circulation
When the fan switch is at FAN ON, the indoor--air fans
operate continuously to provide ventilation. The
thermostat operates the other components as described
above.
Emergency Heat Cycle
If the compressor is inoperative due to a tripped safety
device, the second stage of the thermostat automatically
energizes the indoor--air fan and the electric resistance
heaters.
If desired, the compressor can be manually locked out by
setting the thermostat for emergency heat. In this instance,
the emergency heat indicator light on the thermostat
assembly is illuminated.
Service
Compressor Removal
1. Shut off power to unit. Remove unit access panel.
2. Recover refrigerant from system using refrigerant
recovery methods in accordance with local and
national standards.
3. Disconnect compressor wiring at compressor
terminal box.
4. Disconnect refrigerant lines from compressor.