ICP Pressure Switch for WPG4604090RKB1 — OEM Draft Switch w/ Tubing | Ships Today

Overview

This OEM pressure switch assembly with tubing (part 1178417) is the combustion safety control on the ICP/Tempstar/Heil WPG4604090RKB1 packaged gas unit. It senses negative pressure created by the inducer blower and proves proper venting before the control board allows the igniter and gas valve to fire. If the switch fails to close — or its tubing is cracked, kinked, or clogged with condensate — the furnace locks out on a no-heat fault and will not light. A switch stuck closed is equally dangerous because it defeats the venting safety check.

Specifications

Compatibility

Designed for the ICP WPG4604090RKB1 packaged gas/electric unit and shared-platform Tempstar, Heil, and Comfortmaker WPG-series furnaces. Match the switch's set point (w.c. rating) and port count to your original before installing.

Installation Guide

1. Safety First — Disconnect power at the unit disconnect and verify zero voltage with a multimeter.
2. Access — Remove the burner/control compartment service panel.
3. Document — Photo the switch wiring and the tubing routing to the inducer.
4. Remove — Slide the spade terminals off, detach the tubing, and unscrew the old switch from its bracket.
5. Install — Mount the new switch, reconnect the tubing (no kinks or sags that trap condensate), and reattach the wires per your photo.
6. Test — Restore power, start a heat call, and confirm the switch closes after the inducer starts and the burners light.

Signs You Need a Replacement

• Furnace inducer runs but burners never ignite
• Lockout fault indicating an open pressure switch
• Cracked, brittle, or condensate-filled tubing
• Switch fails a continuity check when the inducer is running

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.