Carrier DesertMaster 50TJM, Operation And Maintenance, Page: 16 / 28

Bold Fan RPM is Factory Setting
Table 6 – Fan RPM at Motor Pulley Settings.
3.7– Condenser Fans and Motors
Fans and motors are factory set. Refer to Condenser-Fan Adjustment Section as required.
3.8– Return – Air Filters
Check that correct filters are installed in filter tracks. See Table 1 “Physical data”. Do not operate unit without
return–air filters.
3.9 – Base Unit Operation
COOLING, UNITS — when thermostat calls for cooling, terminals G and Y1 are energized. The indoor (evaporator)
fan contactor (IFC), and compressor contactor no. 1 (C1) are energized and evaporator-fan motor, compressor no. 1
and condenser fans start. The condenser-fan motors run continuously while unit is cooling. If the thermostat calls for
a second stage of cooling by energizing Y2, compressor contactor no. 2 (C2) is energized and compressor no. 2
starts.
HEATING, UNITS — (If Accessory or Optional Heater is installed) — upon a call for heating through terminal W1,
IFC and heater contactor no. 1 (HC1) are energized.
4.0 – SERVICE
4.1 – Cleaning
Inspect unit interior at beginning of each heating and cooling season and as operating conditions require. Remove
unit top panel and/or side panels for access to unit interior.
EVAPORATOR COIL — Clean as required with a commercial coil cleaner.
CONDENSER COIL — Clean condenser coil annually and as required by location and outdoor-air conditions.
Inspect coil monthly — clean as required.
CONDENSATE DRAIN — Check and clean each year at start of cooling season.
FILTERS — Clean or replace at start of each heating and cooling season, or more often if operating conditions
require. Refer to Table 1 “Physical Data” type and size.
4.2 – Lubrication
Compressors are charged with the correct amount of oil at the factory.
Replacing Compressor - In the case of a motor burnout, the majority of contaminated will be removed with the
compressor. The rest of the oil is cleaned through the use of suction and liquid line filter driers. A 100% activated
alumna suction line filter drier is recommended but must be removed after 72 hours.
The compressor contains POE oil. POE oil has a high affinity for moisture. Do not remove the compressor’s tube
plugs until ready to insert the unit suction and discharge tube ends. The discharge connection plug should be
removed first before pulling the suction connection plug to allow the dry air pressure inside the compressor to
escape.
Note: This is only valid for the R410A systems.
Freq.
Unit
50TJM
MOTOR PULLEY TURNS OPEN
0 1/2 1 1 1/2 2 2 1/2 3 3 1/2 4 4 1/2 5 5 1/2 6
50Hz
18
- - 1030 1001 978 946 918 884 860
830 804 775 745
24
- - 1041 1011 989 956 928 894
870
839 813 784 753
28
- - 1041 1011 989 956 928 894 870
839 813 784 753
34
1029 996 960
928
902 875 847 830 813 791 774 757 740
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