HVACopediaYork · Furnace
Slow green flash Idle - no thermostat call
What the display is showing
Slow flash means 2 seconds on, 2 seconds off. Green slow flash is normal standby with no thermostat call.
Applies to: York TM9V two-stage variable-speed furnace
Settings for these units
Clearance to combustibles · York TM9V
| Side of furnace | Upflow | Downflow | Horizontal |
|---|---|---|---|
| Top / vent / rear / side / front | ? | ? | ? |
| Combustible floor | Yes | Yes (special sub-base only) | Yes |
| Closet | Yes | Yes | Yes |
| Line contact | No | No | Yes |
Leave about 24 in. at the front and 18 in. at the side for service.
Approved for alcove and attic installs.
Filter size by return location · York TM9V
| Airflow | Cabinet | Side return filter | Bottom return filter |
|---|---|---|---|
| 1000 CFM | A | 16 x 25 in. | 14 x 25 in. |
| 1200 CFM | B | 16 x 25 in. | 16 x 25 in. |
| 1600 CFM | C | 16 x 25 in. | 20 x 25 in. |
| 2000 CFM | C | (2) 16 x 25 in. | 20 x 25 in. |
| 2000 CFM | D | (2) 16 x 25 in. | 22 x 25 in. |
Sizes assume high velocity filters (600 FPM); throwaway filters must stay at or below 300 FPM.
Filters go outside the cabinet - never inside the furnace.
Models that show this code
7 models in York TM9V
Other codes on the same units
- 10 red flashes Gas valve powered with no heat call
- 11 red flashes Limit open 5-15 minutes - blower failure
- 13 red flashes High-fire pressure switch open
- LAST ERROR button Read or clear the stored fault codes
- LED steady off Board LED dark - no power to control
- Rapid amber flash Weak flame signal
- Slow amber flash Normal - call for heat
- Steady on (any color) LED lit solid - internal control fault
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Source: York TM9V installation manual 1083294-UIM-A-0114, Furnace Control Diagnostics, p.40. Summarized in our own words; check the original manual for your model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.