AHRI RJNL-B, Руководство по установке

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At initial start-up or after extended shutdown periods make
sure the crankcase heater is energized for at least 12 hours
before the compressor is started.
XVIII. AUXILIARY HEAT
The amount of auxiliary heat required depends on the heat
loss of the structure to be heated and the capacity of the heat
pump. It is good practice to install strip heat to maintain at least
60ºF indoor temperatures in case of compressor failure. The
auxiliary heat is energized by the second stage of the thermo-
stat. The amount of electric heat that is allowed to come on, as
determined by the output of the heat pump, may be controlled
by an outdoor thermostat.
ONLY ELECTRIC HEATER KITS SUPPLIED BY THIS MAN-
UFACTURER AS DESCRIBED IN THIS PUBLICATION HAVE
BEEN DESIGNED, TESTED, AND EVALUATED BY A
NATIONALLY RECOGNIZED SAFETY TESTING AGENCY
FOR USE WITH THIS UNIT. USE OF ANY OTHER MANU-
FACTURED ELECTRIC HEATERS INSTALLED WITHIN
THIS UNIT MAY CAUSE HAZARDOUS CONDITIONS
RESULTING IN PROPERTY DAMAGE, FIRE, BODILY
INJURY OR DEATH.
XIX. DEMAND DEFROST CONTROL
The demand defrost control is a printed circuit board assembly
consisting of solid state control devices with electro-mechani-
cal outputs. The demand defrost control monitors the outdoor
ambient temperature, outdoor coil temperature, and the com-
pressor run-time to determine when a defrost cycle is required.
Enhanced Feature Demand Defrost Control: Defrost
control has high and low pressure control inputs with unique
pressure switch logic built into the microprocessor to pro-
vide compressor and system protection without nuisance
lock-outs. Cycles the compressor off for 5 seconds at the
beginning and end of the defrost cycle to eliminate the
increased compressor noise caused by rapidly changing
system pressures when the reversing valve switches. See
High/Low Pressure Control Monitoring Section below for
diagnostic flash codes for the two diagnostic LED’s provid-
ed on the control.
DEFROST INITIATION
A defrost will be initiated when the three conditions below are
satisfied:
1) The outdoor coil temperature is below 35°F.
2) The compressor has operated for at least 34 minutes with
the outdoor coil temperature below 35°F.
3) The measured difference between the ambient temperature
and the outdoor coil temperature is greater than the calcu-
lated delta T.
Additionally, a defrost will be initiated if six hours of accumulat-
ed compressor run-time has elapsed without a defrost with the
outdoor coil temperature below 35°F.
DEFROST TERMINATION
Once a defrost is initiated, the defrost will continue until four-
teen minutes has elapsed or the coil temperature has reached
the terminate temperature. The terminate temperature is facto-
ry set at 70°F, although the temperature can be changed to
50°F, 60°F, 70°F or 80°F by relocating a jumper on the board.
TEMPERATURE SENSORS
The coil sensor is clipped to a tube on the outdoor coil at the
point fed by the distribution tubes from the expansion device
(short 3/8 dia. tube). The air sensor is located behind a cover
on the control access side of the unit.
If the ambient sensor fails the defrost control will initiate a
defrost every 34 minutes with the coil temperature below 35°F.
If the coil sensor fails the defrost control will not initiate a
defrost.
TEST MODE
Unit must be in a normal heat cycle (compressor running) to
perform a defrost test. A quick short and release of the test
pins will cause a normal defrost cycle. A second short and
release more than 5 seconds after initial short and release will
end the defrost cycle. Test pins shorted without release will
cause a 14 minute defrost that ignores outdoor ambient tem-
perature and outdoor coil temperature.
HIGH/LOW PRESSURE CONTROL MONITORING -
ENHANCED DEFROST CONTROL ONLY
Status of high and low pressure controls is monitored by the
enhanced feature demand defrost control and the following
actions are taken.
High Pressure Control – Provides active protection in both
cooling and heating modes at all outdoor ambient tempera-
tures. The high pressure control is an automatic reset type
and opens at approximately 610 psig and closes at approxi-
mately 420 psig. The compressor and fan motor will stop
when the high pressure control opens and will start again if
the high side pressure drops to approximately 420 psig
when the automatic reset high pressure control resets. If
the high pressure control opens 3 times within a particular
call for heating or cooling operation, the defrost control will
lock out compressor and outdoor fan operation.
Low Pressure Control – Provides active protection in both
heating and cooling modes at all outdoor ambient tempera-
tures. The low pressure control is an automatic reset type
and opens at approximately 15 psig and closes at approxi-
mately 40 psig. Operation is slightly different between cool-
ing and heating modes.
Cooling Mode: The compressor and fan motor will
stop when the low pressure control opens and will start
again when the low side pressure rises to approximate-
ly 40 psig when the low pressure control automatically
resets. If the low pressure switch opens 3 times within a
particular call for cooling operation, the defrost control
will lock out compressor and outdoor fan operation.
Heating Mode: The compressor and fan motor will stop
when the low pressure control opens and will start
again when the low side pressure rises to approximate-
ly 40 psig when the low pressure control automatically
resets. If the low pressure switch trips 3 times within
120 minutes of operation during a particular call for
heating operation, the defrost control will lock out com-
pressor and outdoor fan operation. If the lock-out due to
low pressure occurs at an outdoor ambient temperature
below 5°F, the defrost control will automatically exit the
lock-out mode when the outdoor ambient temperature
rises to 5°F. This feature is necessary since the low
pressure control could possibly have opened due to the
outdoor ambient being very low rather than an actual
system fault.
WARNING
!