What device turns on the blower motor during the cooling cycle for an electric furnace?
In an electric furnace or fan coil setup, the blower motor is typically turned on during the cooling cycle by the blower relay function on the control board (often called the fan control board). On the Icp FSM2X3600A1, that function is commonly handled by the air handler fan control board 1171734.
What the fan control board does in cooling
When your thermostat calls for cooling, the low-voltage signal is processed by the control board, which then energizes the indoor blower at the correct time and speed tap (or programmed speed) to move air across the evaporator coil.
Common control-board responsibilities include:
- Turning the blower on after a cooling call starts
- Keeping the blower running briefly after cooling stops (off-delay)
- Managing blower speed selection (depending on system design)
- Coordinating safety inputs (door switch, limits, condensate safety if equipped)
Quick checks before replacing parts
Shut off power at the breaker before opening any panels; fan coils contain high voltage.
- Confirm the thermostat is set to Cool and the fan is Auto
- Check for a clogged filter that can restrict airflow (use the correct size, such as central air conditioner air filter, 21-1/2 x 19-7/8 x 1-in 1171653 if it matches your setup)
- Verify the indoor unit has power (no tripped breaker, service switch on)
- Inspect for loose or burned wiring at the blower and control board
- If the blower is completely dead, check the low-voltage supply (a failed transformer 1172028 can prevent the control circuit from operating)
Symptoms and likely causes
| Symptom | Most common cause | What it points to |
|---|---|---|
| Outdoor unit runs, indoor blower never starts | Control not energizing blower | Fan control board/relay circuit |
| Blower runs only in “Fan On,” not in cooling | Cooling call not being processed | Thermostat signal or control board |
| Blower hums but will not spin | Motor/capacitor/mechanical issue | Blower motor system (not the relay) |
| No 24V control power | Control power failure | Transformer or wiring issue |
Why it matters
If the blower does not run during cooling, the evaporator coil can freeze and airflow drops sharply; that can lead to poor comfort and additional strain on the system.
Last updated: February 2026
Where is the blower motor located on a heat pump?
On a typical heat pump system, the blower motor is located in the indoor air handler or fan coil, not in the outdoor unit. For your Icp fan coil model FSM2X3600A1, that means the blower motor sits inside the cabinet where the return air filter and evaporator coil are.
What you will usually see when you open the indoor unit
In most fan coil and air handler designs, the blower assembly is positioned to pull air through the filter and coil, then push it into the ductwork.
- Blower motor and blower wheel are in the lower or middle section of the cabinet
- Evaporator coil is typically above the blower (upflow) or beside it (horizontal)
- Filter slot is at the return-air side, upstream of the blower
- Wiring harness and control board are mounted in a separate electrical compartment
- Condensate drain pan is under the coil (near where moisture collects)
Quick location guide (indoor vs. outdoor)
| Component | Typical location | What it does |
|---|---|---|
| Blower motor | Indoor fan coil/air handler | Moves air through ducts |
| Compressor | Outdoor heat pump unit | Pumps refrigerant |
| Condenser fan motor | Outdoor heat pump unit | Moves air across outdoor coil |
Why it matters
If you are troubleshooting weak airflow, noisy operation, or no air movement, checking the indoor fan coil area first saves time. A clogged filter can also make the blower work harder and reduce heating and cooling performance.
Parts that commonly relate to blower and airflow issues
These are common service items we see tied to airflow complaints on fan coil systems:
- Replace a dirty filter with the correct size, such as central air conditioner air filter, 21-1/2 x 19-7/8 x 1-in 1171653
- If the indoor fan will not run or runs erratically, the air handler fan control board 1171734 is a common electrical suspect
- If you have no 24-volt control power (thermostat appears dead), the transformer 1172028 is a common part to test
Last updated: February 2026
Do fan coil units provide heat?
Yes. An Icp fan coil like model FSM2X3600A1 can provide heat when it is paired with a heat source such as an electric heat kit or a hot-water coil, or when it is part of a heat pump system. The fan coil itself moves air across the indoor coil to deliver warm air.
How a fan coil provides heat
A fan coil is the indoor air-moving section; it does not “make” heat by itself in every setup. Heat output depends on what is installed with it.
Common heating configurations include:
- Heat pump system: the indoor coil becomes the heating coil in heating mode
- Electric heat strips (aux heat): electric elements add heat in the air handler
- Hydronic (hot-water) coil: hot water from a boiler warms the coil
- No heat installed: the unit can still circulate air and provide cooling, but not heat
Quick check: what you have at home
Use these clues to identify whether your FSM2X3600A1 setup is configured for heat:
- Thermostat has HEAT mode and the system produces warm air
- You see a separate electric heater compartment attached to the air handler
- There is a hot-water line set going to a coil section (hydronic systems)
- Outdoor unit is labeled as a heat pump (not cooling-only)
What to do if you get little or no heat
If the blower runs but the air is not warm, these are the most common causes:
- Dirty or restrictive filter reducing airflow (replace the central air conditioner air filter, 21-1/2 x 19-7/8 x 1-in 1171653)
- Low voltage control issue (check the transformer 1172028)
- Blower control problem affecting airflow or staging (inspect the air handler fan control board 1171734)
- Thermostat wiring or settings issue
- Heat pump problem (defrost, refrigerant charge, or outdoor unit fault)
Why it matters
Knowing whether your fan coil is configured for heat helps you troubleshoot correctly. A “no heat” complaint can be an airflow problem (filter or blower control) or a missing/failed heat source (electric heat kit, hydronic coil, or heat pump operation).
| Symptom | Most likely area to check first |
|---|---|
| Blower runs, air is cool in HEAT mode | Heat source (heat pump, heat strips, hydronic coil) |
| Weak airflow, rooms never warm up | Filter, blower speed, fan control board |
| Thermostat blank or clicking, no response | Transformer, low-voltage circuit |
Last updated: February 2026
Why is my furnace fan not kicking on?
If the fan on your Icp FSM2X3600A1 fan coil is not kicking on, the most common causes are a thermostat/call-for-fan issue, a power problem (breaker, fuse, door switch), a failed control board, or a low-voltage transformer problem. Start with power and thermostat checks before replacing parts.
Quick checks we recommend first
- Set the thermostat to FAN = ON (not AUTO) and raise/lower temperature to force a call.
- Check the air handler disconnect and your home breaker for the HVAC circuit.
- Confirm the blower compartment door/panel is fully closed (many units have a safety switch).
- Replace a dirty filter; restricted airflow can trigger safeties or overheating.
- Look for burnt wiring, loose spade connectors, or corrosion on control terminals.
Parts that commonly cause “fan won’t run”
If power is present and the thermostat is calling for fan, these parts are common suspects for this model:
| Symptom | What it usually points to | Part to check |
|---|---|---|
| No blower response in heat/cool or FAN ON | Control not sending blower command | Air handler fan control board 1171734 |
| No 24 VAC control power (thermostat dead) | Failed low-voltage supply | Transformer 1172028 |
| Fan runs weak, freezes up, or short-cycles | Airflow restriction | Central air conditioner air filter, 21-1/2 x 19-7/8 x 1-in 1171653 |
Safe troubleshooting steps (power off when opening panels)
- Turn off power at the breaker/disconnect before removing access panels.
- Inspect the filter and return air path; replace the filter if it is loaded with dust.
- If you have a multimeter, verify 24 VAC at the control circuit and thermostat wiring.
- Check for a blown low-voltage fuse on the control board (if equipped).
- If the blower hums but will not spin, stop and have the motor/capacitor circuit checked by a technician.
For meter basics, we use the same approach shown in how to use a multimeter to test electrical parts video.
Why it matters
A fan that does not run can quickly lead to no heat/no cooling, coil freeze-up, or overheating shutdowns. Fixing airflow and control-power issues early helps prevent bigger repairs.
Last updated: February 2026
What are the parts of the HVAC heat pump system?
An HVAC heat pump system is made up of an outdoor unit (compressor and coil) and an indoor air handler or fan coil like the Icp FSM2X3600A1, plus controls, refrigerant lines, and air distribution. Inside the fan coil, the filter, blower, and electrical controls are key service parts.
Main parts you will typically find in a heat pump system
- Outdoor unit: compressor, outdoor coil, condenser fan motor, defrost controls
- Indoor unit (fan coil/air handler): evaporator coil, blower motor and wheel, drain pan and condensate drain
- Refrigerant circuit: suction line, liquid line, metering device (TXV or piston), service valves
- Electrical and controls: thermostat, low-voltage transformer, relays/boards, safety switches
- Air distribution: return duct, supply duct, registers, return grille
Common service parts for Icp FSM2X3600A1
These are examples of parts we commonly see replaced on fan coils and air handlers:
- Central air conditioner air filter, 21-1/2 x 19-7/8 x 1-in 1171653 (protects the coil and blower from dust)
- Air handler fan control board 1171734 (controls indoor blower operation and fan speeds)
- Transformer 1172028 (steps line voltage down to low voltage for controls)
Quick comparison: what each part does
| Part | Where it is | What it affects when it fails |
|---|---|---|
| Air filter | Return air path | Low airflow, icing, poor heating/cooling, higher energy use |
| Fan control board | Indoor unit control section | Blower not running, wrong speed, intermittent operation |
| Transformer | Indoor unit electrical section | No 24V control power, thermostat appears dead |
Why it matters
Knowing which section you are working on (outdoor unit vs. indoor fan coil vs. controls) helps you troubleshoot faster and order the right replacement part the first time. On the FSM2X3600A1, airflow and control-power issues often trace back to the filter, fan control board, or transformer.
Last updated: February 2026
