Friedrich
Heating & Cooling Combined Unit

Model # THC12K50 Official Friedrich central packaged terminal unit

Here are the diagrams and repair parts for Official Friedrich THC12K50 central packaged terminal unit, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 106 parts  |

Blower Scroll 21058350
#34

Air handler diagram

Blower scroll

Part #21058350

The manufacturer no longer makes this part, and there's no substitute part

Fuse,time 21058448
#74C

Control box assembly diagram

Fuse,time

Part #21058448

The manufacturer no longer makes this part, and there's no substitute part

Isolator 21063375
#42

Air handler diagram

Isolator

Part #21063375

The manufacturer no longer makes this part, and there's no substitute part

Thermostat 21059023

#NI08

All parts diagram

Thermostat

Part #21059023

The manufacturer no longer makes this part, and there's no substitute part

Short Shaft 25009600
#40

Air handler diagram

Short shaft

Part #25009600

The manufacturer no longer makes this part, and there's no substitute part

Relay 21058148
Relay

Part #21058148

The manufacturer no longer makes this part, and there's no substitute part

Access Cover 21062325
#32

Air handler diagram

Access cover

Part #21062325

The manufacturer no longer makes this part, and there's no substitute part

Thermostat Knob 21058437
#66

Control box assembly diagram

Thermostat knob

Part #21058437

The manufacturer no longer makes this part, and there's no substitute part

Drain Kit 25031800

#NI12

All parts diagram

Drain kit

Part #25031800

The manufacturer no longer makes this part, and there's no substitute part

Transformer 21091226

#NI10

All parts diagram

Transformer

Part #21091226

The manufacturer no longer makes this part, and there's no substitute part

Most common symptoms to help you fix your heating & cooling combined units

Choose a symptom to see related heating and air conditioning system repairs.

Thermostat problem, clogged air filter, burner failure…

Dirty air filter, clogged condenser coils, low refrigerant charge, faulty compressor…

Thermostat problems, bad compressor/condenser fan capacitor, lack of refrigerant, failed compressor…

Main causes: errant thermostat settings, lack of electrical power, clogged drain line, wiring failure, control failure.…

Main causes: Errant thermostat settings, lack of power, bad interlock switches, lack of exhaust ventilation, wiring fail…

Dirty flame sensor, failed flame sensor, damaged burner, bad high limit switch…

Most common repair guides to help fix your heating & cooling combined units

These step-by-step repair guides will help you safely fix what’s broken on your HVAC system.

How to unclog the air conditioner drain line

How to unclog the air conditioner drain line

The condensate drain line for your central air conditioner can clog with mold and mildew. Water will back up and start d…

Repair difficulty
Time required
 15 minutes or less
How to replace the furnace flame sensor

How to replace the furnace flame sensor

The flame sensor detects when furnace burner flames are lit. You may need to replace the flame sensor if flames only sta…

Repair difficulty
Time required
 15 minutes or less
How to replace a heating and air conditioning system thermostat

How to replace a heating and air conditioning system thermostat

The control thermostat for your HVAC system can stop working. This repair guide shows how to replace it.…

Repair difficulty
Time required
 30 minutes or less

Effective articles & videos to help repair your heating & cooling combined units

Use the advice and tips in these articles and videos to get the most out of your HVAC system.

Maintaining your air conditioner

Maintaining your air conditioner

Learn how to maintain your central air conditioner to keep it running smoothly all summer long.…

How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…