Furnace Pressure Switches
We sell directly to the homeowner
A pressure switch is a safety interlock that proves the draft inducer is actually moving air before the control board will open the gas valve. It senses the negative pressure the inducer creates through a small hose; no vacuum, no gas. Most "stuck open" faults are not the switch at all — they are the switch correctly reporting a venting problem.
520 pressure switches in stock, ready for same-day pickup at our Coquitlam warehouse or shipped worldwide.
Signs your pressure switche may have failed
- Inducer runs, then everything stops before the ignitor glows
- Control board reports pressure switch stuck open, or stuck closed
- Failure is intermittent and worse in wind, rain, or hard frost
- Water visible in the pressure hose or the inducer port
Not sure which part you need? Call 1-778-759-9864 with your furnace model number and we will confirm it before you order.
Shop pressure switches by brand
Pressure Switches we stock
LENNOX SWITCH, LOW PRESSURE
LENNOX SWITCH, LOW PRESSURE
LENNOX PRESSURE SWITCH, LOW AMBIENT, OPENS 150F, CLOSES 275F
LENNOX TUBING KIT, PRESSURE SWITCH, BLACK & RED
LENNOX HIGH PRESSURE SWITCH, ACTUATES AT 410 PSI; MANUAL RESET
LENNOX SWITCH - PRESSURE
LENNOX TUBING, PRESSURE SWITCH
LENNOX SWITCH, HIGH PRESSURE, 450/300
102448-01 SWITCH-HIGH PRESSURE (640PSI)
Pressure Switch, 1.25" Water Column, SPST
Airswitch Safety Interlock Pressure Switch, SPST, Normally Open
LOSS OF CHARGE PRESSURE SWITCH, ACTUATES AT 55 PSI; RESETS AT 25 PSI
Switch, High Pressure, Cutout 450, Manual Reset
Pressure Switch, 0.47" WC, SPST
High Pressure Switch, Actuates at 640 PI/Resets at 475 PSI, SPST, Normally Closed
LENNOX SWITCH, HIGH PRESSURE, 120/240V, MANUAL RESET
LENNOX SWITCH, HIGH PRESSURE, 590 # CUTOUT, MANUAL RESET
LENNOX PRESSURE TRANSDUCER
LENNOX SWITCH-PRESSURE (LOW FIRE) 1.35"WC
LENNOX PRESSURE SWITCH TUBING KIT
SWITCH; PRESSURE, SPST 0.90"WC
SWITCH; HIGH PRESSURE, BRAZED, SPST, OPE
SWITCH; PRESSURE-.70
SWITCH; PRESSURE-.65
Pressure Switch, Dual, 0.50"WC/0.17"WC
SWITCH, PRESSURE, OPEN AT -1.51 WC,
Air Pressure Control Switch, SPST, 0.20" WC
Image coming soon
000-429
SWITCH PRESSURE
Image coming soon
001-118
LENNOX SWITCH, PRESSURE - YK-4.4
Image coming soon
020-067
SWITCH; HIGH PRESSURE, SPST, OPEN @ 650
Image coming soon
020-068
SWITCH; LOW PRESSURE, OPEN @ 50 PSIG, CL
Image coming soon
020-069
SWITCH; LOW PRESSURE, OPENS AT 35 PSI AN
Image coming soon
020-550
SWITCH; PRESSURE-.72
Image coming soon
021-295
CONTROL, AIR PRESSURE, -.45 IN WC OPEN,
Image coming soon
021-865
SWITCH,DIFFERENTIAL PRESSURE, SPDT, 32-1
Image coming soon
021-867
SWITCH PRESSURECUTOUT 120240 VAC - 1
Image coming soon
021-870
SWITCH DIFFERENTIAL PRESSURE -40 TO 15
Image coming soon
021-872
SWITCH, AIR FLOW
Image coming soon
021-876
SWITCH SPDT 25AMP 277V PRESSURE
Image coming soon
021-877
SWITCH, SPDT, 22 AMPS, 480V, PRESSURE
Image coming soon
021-878
SWITCH PRESSURE SPDT 300 VA AT 120-27
Image coming soon
021-881
SWITCH; CONTROL, LOW PRESSURE, 8 OPEN, 2
Image coming soon
021-883
SWITCH HIGH PRESSURE CUTOUT 800 PSIG
Image coming soon
021-885
SWITCH, LOW PRESSURE 25 OP/41 CL
Image coming soon
021-886
SWITCH; LOW PRESSURE, OPEN @ 50 PSIG CLO
Image coming soon
021-887
SWITCH, HIGH PRESSURE, BRAZED, OPENS AT
Image coming soon
021-888
SWITCH; HIGH PRESSURE, SPST, OPEN @ 650
Image coming soon
021-889
SWITCH; HIGH PRESSURE SPST OPEN @ 650
Showing 48 of 520. Pick your brand above for the full list, or browse every part by number.
Pressure Switches questions
- What does "pressure switch stuck open" actually mean?
- The board energised the inducer and then waited for the switch to close, and it never did. Before replacing the switch, check the obvious causes: a blocked or cracked hose, a plugged inducer port, a blocked or iced-over vent termination, a full condensate trap, or a failing inducer that no longer pulls its rated draft. The switch is frequently the messenger, not the fault.
- What about "pressure switch stuck closed"?
- The board found the switch already closed before the inducer started, so it cannot verify the safety. That usually means welded contacts inside the switch — a genuine replacement case — or a hose left connected to the wrong port.
- Does the pressure rating on the switch matter?
- Yes, and it is the number to match. Switches are rated in inches of water column — for example −0.40" WC — and that setpoint is chosen for your specific furnace and vent configuration. A switch with the wrong rating either nuisance-trips or fails to protect you. Match the rating stamped on the old switch, not just the physical shape.
Need it today in Greater Vancouver?
Call ahead and we will set the part aside at the Coquitlam counter. No account, no trade card, no minimum order.