IN-WARRANTY RETURN MATERIAL PROCEDURE
COMPRESSOR
Copeland
Refrigeration Corporation has stocking wholesalers
who maintain a stock of replacement compressors and ser-
vice parts to serve refrigeration contractors and servicemen.
When a compressor fails in warranty, contact your local
sales representative, or McQuay Warranty Claims Deparment
at the address on the cover of this bulletin. You will be
authorized to exchange the defective compressor at a
Copeland
wholesaler, or an advance replacement can be ob-
tained. A credit is issued you by the wholesaler for the re-
turned compressor after Copeland factory inspection of the
inoperative compressor. If that compressor is out of
Copeland’s warranty, a salvage credit only is allowed. Pro-
vide McQuay with full details; i.e., McQuay unit model and
unit serial numbers. Include the invoice and the salvage value
credit memo copies and we will reimburse the difference. In
this transaction, be certain that the compressor is definitely
defective. If a compressor is received from the field that tests
satisfactorily, a service charge plus a transportation charge
will be charged against its original credit value.
On all out-of-warranty compressor failures, Copeland of-
fers the same field facilities for service and/or replacement
as described above. The credit issued by Copeland on the
returned compressor will be determined by the repair charge
established for that particular unit.
COMPONENTS OTHER THAN COMPRESSORS
Material may not be returned except by permission of
authorized factory service personnel of McQuay Air Condi-
tioning at Minneapolis, Minnesota. A “return goods” tag will
be sent to be included with the returned material. Enter the
The return of the part does not constitute an order for
replacement. Therefore, a purchase order must be entered
through your nearest McQuay representative. The order
information as called for on the tag in order to expedite han-
dling at our factories and prompt issuance of credits.
should include part name, part number, model number and
serial number of the unit involved.
Following our personal inspection of the returned part, and
All parts shall be returned to the pre-designated McQuay
factory transportation charges prepaid.
if it is determined that the failure is due to faulty material or
workmanship, and in warranty, credit will be issued on
customer’s purchase order.
APPENDIX
STANDARD CONTROLS
NOTE: PERFORM AN OPERATIONAL CHECK ON ALL UNIT SAFETY CONTROLS ONCE PER YEAR.
OIL PRESSURESAFETY CONTROL
The oil pressure safety control is a manually resettable device
which senses the differential between oil pressure at the
discharge of the compressor oil pump and suction pressure
inside the compressor crankcase. When the oil pressure
reaches approximately 15 psi above the crankcase suction
pressure, the pressure actuated contact of the control opens
from its normally closed position. If this pressure differential
cannot be developed, the contact will remain closed and
energize a heater element within the control. The heater ele-
ment warms a normally closed bimetallic contact and causes
the contact to open, de-energizing a safety relay and break-
ing power to the compressor.
minutes for the heater element and bimetallic contacts to cool
and reset the control again.
It takes about 120 seconds to warm the heater element
enough to open the bimetallic contact, thus allowing time for
the pressure differential to develop.
If during operation, the differential drops below 10 psi, the
heater element will be energized and the compressor will
stop. The control can be reset by pushing the reset button
on the control. If the compressor does not restart, allow a few
To check the control, pump down and shut off all power
to the unit. Open the circuit breakers or the fused discon-
nect for that compressor and install a voltmeter between ter-
minals L and M of the oil pressure control. Turn on power
to the unit control circuit (separate disconnect or main unit
disconnect depending on the type of installation). Check to
see that the control stop switch
S1
is in the “on” position.
The control circuit should now be energized, but with the
absence of compressor power, no oil pressure differential can
develop and thus the pressure actuated contacts of the con-
trol will energize the heater element and open the bimetallic
contacts of the control within 120 seconds. When this hap-
pens, the safety relay is de-energized, the voltmeter reading
will rise to
24V,
and the compressor contactor should open.
Repeated operations of the control will cause a slight heat
buildup in the bimetallic contacts resulting in a slightly longer
time for reset with each successive operation.
Pressure Actuator
Contact
Heater Element
Neutral
Line
Note 2
L M
*I
IX
Bimetallic Contacts
Neutral
Safety Relay
IM 269
/
Page 51
To Next Page
Loading...
Need help?
General