York Error Code 3 double red flashes: Second-stage pressure switch not closing (Furnace)
York error code 3 double red flashes on a furnace means: Second-stage pressure switch not closing. It is also called York diagnostic code 3 double red flashes.
Homeowner? What York code 3 double red flashes means for you
Check, then call Your furnace is reporting: Second-stage pressure switch not closing. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.
- Make sure the furnace front door or panel is closed properly; many furnaces will not run with the door switch open.
- Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
- Outside, make sure the intake and exhaust pipes or vent cap are not blocked by snow, ice, leaves or a nest.
- Check that the gas valve next to the furnace is open (handle in line with the pipe). Do not force it.
- Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does York error code 3 double red flashes mean?
Two-stage boards (UTEC / White-Rodgers): the high-fire pressure switch stays open on a second-stage call. TM9V boards report this as 13 red flashes instead.
Applies to: York/JCI residential gas furnaces: York UTEC IFC furnaces, York White-Rodgers IFC furnaces
Common causes of York code 3 double red flashes
- Partly blocked vent or intake
- Inducer not reaching high speed
- Hose or wiring problem at the high-fire switch
A technician checks these and 1 other possible causes on site before replacing any part.
Other York Furnace codes
All York Furnace error codes →
York code 3 double red flashes: homeowner questions
What does York code 3 double red flashes mean?
Second-stage pressure switch not closing. Two-stage boards (UTEC / White-Rodgers): the high-fire pressure switch stays open on a second-stage call. TM9V boards report this as 13 red flashes instead.
Is it safe to keep using my furnace with code 3 double red flashes?
It depends on the cause. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Can I reset York code 3 double red flashes myself?
You can try one reset (power off for 30 seconds, then on). If York code 3 double red flashes comes back, the cause is still there and a licensed technician should check it.
Who can fix York code 3 double red flashes near me?
Aurora Star Tech Inc. repairs York furnaces in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: Furnace Not Turning On: What to Check · Furnace Blinking Light: What the Flash Codes Mean
Troubleshooting guides
- Blowing cold air All brands · Furnace
- No heat All brands · Furnace
- Short cycling All brands · Furnace
Source: York All JCI single-two-stage furnaces with UTEC IFC board codes ST-045-09.pdf - section Fault Code LED Flashes; York JCI single-two-stage furnaces with White-Rodgers-Emerson IFC (older installed base) codes ST-028-07.pdf - section Fault Code Sheets. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.