Classic HVPA & HVPSA M&S 8.09-1
15700 - 5
HVAC Equipment
2.1 START-UP PROCEDURE
Important: If your unit has a crankcase heater be sure that the crankcase heater has been
energized for at least 24 hours prior to start-up of the unit. Double check all electrical con-
nections before applying power. Various thermostats can be used to control the heat pump.
The thermostat may have a fan switch with an Automatic and On positions, a system switch
with Heat, Cool, and Off positions, and an emergency heat position with lights. The spec
sheets have detailed description of the various Marvair
®
thermostats. Since other thermo-
stats or remote control systems may be used, the following procedures should be viewed as
guidelines for standard thermostats with system and fan switches.
Check-out of Cooling Cycle
Procedure:
Classic™ Heat Pump
1. Set the fan switch to "Auto" and the system switch to "Off".
2. Move the cooling temperature on the wall thermostat to a point
higher
than the
room temperature. Move the heating temperature to a temperature that is
lower
than the room temperature.
3. Set the thermostats system switch to "Cool" or "Auto" position. Nothing should
operate at this time.
4. Set the time delay in the control box to three minutes. Note that time delay is an
option on some Classic™ units and may not be on your heat pump.
5. Remove the cover plate from the thermostat. Slowly lower the thermostat cooling
temperature. Once the indoor fan turns on, allow approximately three minutes for
the compressor and outdoor fan to start.
For units equipped with the low ambient control, note that the outdoor fan may not
come on immediately, because it is cycled by refrigerant pressures. Some units have
a time delay module which prevents the compressor from restarting immediately
after interruption of power. See section 1.5P and 1.5Q for details on the operation of
the low ambient control and the time delay.
If the unit fails to operate, refer to the troubleshooting information in Chapter 6.1.
Classic™ Heat Pump with Economizer
1. Set the fan switch to "Auto" and the system switch to "Off".
2. Set the cooling temperature on the wall thermostat to a point
higher
than the room
temperature. Set the heating temperature to a temperature that is
lower
than room
temperature.
3. Set the thermostat system switch in the "Auto" or "Cool" position. Nothing should
operate at this time.
