Sullair RC Series - Refrigerant Compressor Not Running

SECTION 7 TROUBLESHOOTING
149
Dryer-on light is lit but
Refrigerant Compressor
does not run.
Clogged condenser fins
or clogged water
condenser.
Clear fins or water
condenser of all
obstructions.
The clogged fins in the
condenser will restrict the air
passage and reduce the
refrigeration capacity,” causing
high temperature in the
evaporator. Same will occur if
water condenser is clogged with
mud or dirt. Air condenser and
water condenser should be
periodically checked and
cleaned. Protect water circuit by
an adapted filter.
Possible high crankcase
temperature
Possible loss of phase
Possible low voltage
causing overload trip
Possible failed
compressor
Too much compressed air
flow.
Check actual flow through
the dryer.
This dryer is designed for a
maximum air flow at design
conditions. If too much air is
pumped into the dryer, water
removal capacity may not be
sufficient, resulting in liquid
carryover downstream. Check
the rated output the air
compressor.
Faulty electrical wiring Inspect the circuit The compressor-on light should
be wired into the refrigerant
compressor circuit. See wiring
diagram in chapter “Drawings”
of this manual.
One electrical protection
has tripped.
Reset the protection or
replace the blown fuse.
The dryer is protected against
high amp draw by fuse and/or
overload relay that can trip in
case of need. Reset or replace
fuse once, but do not persist if it
trips again, request assistance
from a qualified refrigeration
contractor.
Dryer-on light is lit but fan
is not running.
Fan has to run if
refrigerant high pressure
reaches upper set point.
Check that compressed
air flows through the
dryer. Check that fan
blades are free to move.
Fan operates automatically to
keep refrigerant pressure below
the maximum value. The fan
can stop if pressure is under the
recommended setting.
Check the fan pressure
switch.
When compressor starts,
it vibrates a lot and
makes mechanical noise.
Compressor is slugging
liquid refrigerant at start-
up.
Be sure the pre-heating
period of at least 4 hours
is respected for dryers
equipped with a
crankcase heater.
Refrigerant may move between
receivers when refrigerant
compressor is stopped and not
heated, especially if stopped for
a long time. This migration may
cause liquid shock (slugging) in
valves specially on large dryers
containing more refrigerant.
PROBLEM
POSSIBLE CAUSE REPAIR COMMENTS