7
4.
Turn the fan switch to the “ON” position. The blower should
operate after a 7 second delay.
5.
Turn the fan switch to “Auto” position. The blower should
stop after a 65 second delay.
6.
Slowly lower the cooling temperature until the unit starts.
The compressor, blower and fan should now be operating.
Allow the unit to run 10 minutes, make sure cool air is
being supplied by the unit.
7.
Turn the temperature setting to the highest position,
stopping the unit. The indoor blower will continue to run for
65 seconds.
8.
Turn the thermostat system switch to “OFF” and disconnect
all power when servicing the unit.
HIGH VOLTAGE!
DISCONNECT ALL POWER BEFORE INSTALLING OR
SERVICING. MULTIPLE POWER SOURCES MAY BE
PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
WARNING
Heat Pump Start-Up Procedure
9.
Check the cooling mode for the heat pump in the same
manner as above. The reversing valve is energized when
the thermostat is placed in the cooling position. A clicking
sound should be noticeable from the reversing valve. By
lowering the temperature setting to call for cooling, the
contractor is energized. The compressor, blower and fan
should then be running. After the cooling mode is checked
out, turn the thermostat system switch to “OFF
”.
10. Turn the thermostat system switch to “HEAT” and fan switch
to “AUTO
”.
11. Slowly raise the heating temperature setting. When the
heating first stage makes contact, stop raising the
temperature setting.. The compressor, blower and fan
should now be running with the reversing valve in the de-
energized (heating) position. After giving the unit time to
settle out, make sure the unit is supplying heated air.
12. If the out door ambient is above 80°F, the unit may trip on
its high pressure cut out when on heating. The compressor
should stop. The heating cycle must be thoroughly
checked, so postpone the test to another day when
conditions are more suitable but-DO NOT FAIL TO TEST.
If the out door ambient is low and the unit operates properly
on the heating cycle, you may check the pressure cutout
operation by blocking off the indoor return air until the unit
trips.
13. If unit operates properly in the heating cycle, raise the
temperature setting until the heating second stage makes
contact. Supplemental resistance heat, if installed should
now come on. Make sure it operates properly.
NOTE: If outdoor thermostats are installed the outdoor
ambient must be below the set point of these
thermostats for the heaters to operate. It may be
necessary to jumper these thermostats to check heater
operation if outdoor ambient is mild.
14. For thermostats with emergency heat switch, return to step
11. The emergency heat switch is located at the bottom of
the thermostat. Move the switch to emergency heat. The
heat pump will stop, the blower will continue to run, all
heaters will come on and the thermostat emergency heat
light will come on.
15. If checking the unit in the wintertime, when the outdoor coil
is cold enough to actuate the defrost control, observe at
least one defrost cycle to make sure the unit defrosts
completely.
Final System Checks
16. Check to see if all supply and return air grilles are adjusted
and the air distribution system is balanced for the best
compromise between heating and cooling.
17. Check for air leaks in the ductwork.
18. See Sections on
Air Flow Measurement and Adjustment
and
Checking Charge
.
19. Make sure the unit is free of “rattles”, and the tubing in the
unit is free from excessive vibration. Also make sure tubes
or lines are not rubbing against each other or sheet metal
surfaces or edges. If so, correct the trouble.
20. Set the thermostat at the appropriate setting for cooling
and heating or automatic changeover for normal use.
21. Be sure the Owner is instructed on the unit operation, filter,
servicing, correct thermostat operation, etc.
The foregoing “Start-up Procedure and Check List” is
recommended to serve as an indication that the unit will
operate normally.
COMPONENTS
1.
Contactor
- This control is activated (closed) by the room
thermostat for both heating and cooling. The contactor has
a 24V coil and supplies power to the compressor and
outdoor fan motor.
2.
Crankcase Heater –
This item is “ON” whenever power
is
supplied to the unit. It warms the compressor crankcase
thereby preventing liquid migration and subsequent
compressor damage. The insert type heater is self
regulating. It is connected electrically to the contactor L1
and L2 terminals.
3.
Condenser Motor -
This item is activated by the contactor
during heating and cooling, except during defrost and
emergency heat operation.
4.
Compressor -
This item is activated by the contactor for
heating and cooling, except during emergency heat. It is
protected by
an internal overload.
5.
Contactor Relay -
This control is activated by the thermostat
(24V coil) and supplies power to the contactor.
6.
Defrost Control
- The Defrost control provides time/
temperature initiation and termination of the defrost cycle.
When a Defrost cycle is initiated, the defrost control shifts
the reversing valve to “cooling” mode, stops the outdoor
fan and brings on supplemental heat. Normally, a Defrost
cycle will take only 2-3 minutes unless system is low on
charge or outdoor conditions are severe. (Windy and cold)
7.
Outdoor Thermostat -
These optional controls are used
to prevent full electric heater operation at varying outdoor
ambient (0° F-to 45° F). They are normally open above
their set points and closed below to permit staging of
indoor supplement heater operation. If the outdoor ambient
temperature is below 0° F (-18° C) with 50% or higher RH,
an outdoor thermostat (OT) must be installed and set at
(0°) on the dial. Failure to comply with this requirement
may result in damage to the product which may not be
covered by the manufacturer’s warranty.
8.
Reversing Valve Coil -
This coil is activated by the
thermostat, in the cooling mode and during defrost. It
positions the reversing valve pilot valve for cooling
operation.
