Installation
RT-SVX33E-EN
25
Compressor Crankcase Heaters
Each compressor is equipped with a crankcase heater. The
proper operation of the crankcase heater is important to
maintain an elevated compressor oil temperature during
the “Off” cycle to reduce oil foaming during compressor
starts. Oil foaming occurs when refrigerant condenses in
the compressor and mixes with the oil. In lower ambient
conditions, refrigerant migration to the compressor could
increase.
When the compressor starts, the sudden reduction in
crankcase pressure causes the liquid refrigerant to boil
rapidly causing the oil to foam. This condition could
damage compressor bearings due to reduced lubrication
and could cause compressor mechanical failures.
Before starting the unit in the “Cooling” mode, set the
system switch to the “Off” position and turn the main
power disconnect to the “On” position and allow the
crankcase heater to operate a minimum of 8 hours.
Before closing the main power disconnect switch, insure
that the “System” selection switch is in the “Off” position
and the “Fan” selection switch is in the “Auto” position.
Close the main power disconnect switch and the unit
mounted disconnect switch, if applicable.
ReliaTel Controls
Upon power initialization, the RTRM performs self-
diagnostic checks to insure that all internal controls are
functional. It also checks the configuration parameters
against the components connected to the system. The
Liteport LED located on the RTRM module is turned “On”
within one second of power-up if internal operation is
okay.
Use one of the following “Test” procedure to bypass some
time delays and to start the unit at the control panel. Each
step of unit operation can be activated individually by
temporarily shorting across the “Test” terminals for two to
three seconds. The Liteport LED located on the RTRM
module will blink when the test mode has been initiated.
The unit can be left in any “Test” step for up to one hour
before it will automatically terminate, or it can be
terminated by opening the main power disconnect switch.
Once the test mode has been terminated, the Liteport LED
will glow continuously and the unit will revert to the
“System” control.
Final Steps
Use the checklist provided below in conjunction with the
checklist in
“General Unit Requirements,” p. 18
, to ensure
that the unit is properly installed and ready for operation.
•
Check all electrical connections for tightness and
“point of termination” accuracy.
•
Verify that the condenser airflow is unobstructed.
•
Verify that the condenser fan and indoor blower turn
freely without rubbing and are properly tightened on
the shafts.
•
Check the supply fan belts for proper tension and the
fan bearings for sufficient lubrication. If the belts
require adjustment, or if the bearings need lubricating,
refer to the maintenance section of this manual for
instructions.
•
Verify that a condensate trap is installed and the piping
is properly sized and pitched.
•
Verify that the correct size and number of filters are in
place.
•
Inspect the interior of the unit for tools and debris and
install all panels in preparation for starting the unit.
NOTICE:
Compressors Failure!
Unit must be powered and crankcase heaters energized
at least 8 hours BEFORE compressors are started. This
will protect the compressors from premature failure.
