HK06WC091 – PRESSURE SWITCH

Furnace air-proving pressure switch from Carrier’s HK06WC family, the same series as HK06WC069 and HK06WC090, used in Carrier, Bryant and Payne gas furnaces. It senses the negative pressure developed by the draft inducer and must close before the control will energize the igniter and gas valve. Carrier does not publish public part detail outside its gated dealer portal, so no water-column setpoint is listed here – read the rating printed on the switch you are removing and match it exactly.

Specifications from our own stock records. The manufacturer does not publish a public page for this item.

Before you order

IMPORTANT: Carrier’s own description for this part is PRESSURE SWITCH, SPST, HIGH FIRE — it is the high-fire (second stage) switch on two-stage furnaces. Its low-fire counterpart is HK06WC092. It is NOT the same part as HK06WC090, which is a single-stage switch with no stage designation and a different supersession history; the two are not interchangeable. Carrier has discontinued this number in favour of HK06MC110. Published application data. Always match the full model and serial number on your unit before ordering.

Specs

• Part NumberHK06WC091
• Brand (as recorded)Carrier
• Product TypeFurnace air pressure switch
• SeriesHK06WC
• Setpoint (W.C.)Not published - verify on switch body
• FunctionProves inducer draft before ignition
• Data SourceOTP stock record - not manufacturer-verified

Fits these models

• 58CVA and 58CVX 070 / 090 / 110 / 135 / 155 series
• 58STA, 58STX, 58STK 045 / 070 / 090 / 110 / 135 series
• 58CTA, 58CTX, 58CTW, 58CTY 070 / 090 / 110 / 135 series
• 58DLA and 58DLX 070 / 090 / 110 / 135 / 155 series
• 58PHA, 58PHB, 58PHX 045 / 070 / 090 series
• 58TP1A045V141212, 58TP1A135V241122, 58TN1A090C171116
• 310AAV, 310JAV, 311AAV, 311JAV series
• 312AAV, 312JAV, 313AAV, 313JAV, 313JBV series
• 315AAV 048090, 066135, 066155 series

What does the furnace pressure switch prove?

It is a normally open switch on a hose running to the inducer housing or the heat exchanger. When the inducer spins up and pulls enough negative pressure, the contacts close and the board is allowed to light the burners. A switch marked -0.75 in. W.C. closes at three quarters of an inch of water column of vacuum. That is the furnace verifying draft before it makes fire.

Mine will not close. Do I need a new switch?

Usually not, because these do not fail all that often. On a 90 percent furnace look at the condensate trap and drain line first - water backing up into the secondary heat exchanger is the most common cause we hear about. After that, the hose (cracked, kinked, or full of crud and water), the port on the inducer housing, the flue and intake for a bird or wasp nest, and the inducer itself for weak amp draw or a chewed up wheel.

How do I pick the right one?

Read the setpoint off the switch body. It is printed or stamped right there, along with whether it is a single or two-stage switch. Do not guess by looks - the same housing gets built at a half dozen different pressures, and -0.75, -0.80 and -0.85 in. W.C. are indistinguishable on the shelf. Bring the old switch or a clear photo of the label.

Can I jump it out to get heat tonight?

No. That switch is what keeps a blocked flue from pushing combustion gas into the house instead of out the roof.