KeepRite Gas Furnace Error Code 3 flashes: Pressure switch did not close (or reopened)

KeepRite gas furnace showing code 3 flashes on the ICP/KeepRite gas furnace control board? The inducer started but the pressure switch did not close (or closed then reopened during the cycle), so the control cannot prove adequate venting/combustion airflow and will not allow ignition. Here is what it means, what you can safely check, and when to call a licensed CANRO technician in an urgent situation across Metro Vancouver.

Likely causes of KeepRite code 3 flashes

• Weak or failing inducer motor
• Blocked intake or exhaust vent / blocked condensate drain (high-efficiency)
• Disconnected, cracked or water-filled pressure tubing
• Defective pressure switch stuck open
• Excessive wind or improper vent sizing/length

What you can safely check first

• Check outdoor intake/exhaust terminations for snow, ice, leaves, or nests
• Confirm nothing is blocking the vent pipes
• Verify the condensate drain is not clogged or frozen (high-efficiency models)
• Reset by cycling the thermostat once; if it repeats, call a technician

What not to touch: beyond these checks, do not open the unit or touch the gas valve, wiring, control board or refrigerant lines. In BC, gas and HVAC repairs must be done by a licensed technician — both for your safety and to keep your manufacturer warranty valid.

Repair or replace your KeepRite gas furnace?

A single fault code rarely means you need a new gas furnace. The deciding factors are the unit’s age, the cost of the failed component versus its efficiency, and whether it’s a recurring problem. Our technicians give you an honest diagnosis and a written repair-or-replace recommendation — never a scare-sell. Explore more gas furnace guides and services or browse all HVAC error codes we fix.

Frequently asked questions

Applies to KeepRite ICP/KeepRite gas furnace control board. Code behaviour can vary by model and control board — our technician confirms the exact cause against your unit before any repair.

CANRO Heating & Cooling — TSBC Class-A gas-fitting licence · Red Seal HVAC certified · WorkSafeBC and liability insured · 4.9★ from 85+ Google reviews · Serving Metro Vancouver since 1999.