R68DD0014 Mortex Pressure Switch 

The R68DD0014 is a factory‑specified 0.20" WC pressure switch used in Mortex and Heat Controller furnaces. This switch monitors combustion‑air draft and closes only when the induced draft blower creates the correct negative pressure.

If the switch does not close, the furnace will lock out ignition to prevent unsafe burner operation. This OEM switch restores proper safety proving when the original becomes weak, stuck, or fails to close.

• This confirms the R68DD0014 is OEM‑specific and not interchangeable with generic adjustable switches or higher WC ratings.

Cross‑Reference

Direct OEM

• R68DD0014 — Mortex / Heat Controller 0.20" WC Pressure Switch

Related Mortex Pressure Switches (Not direct replacements)

• R68DD0015 — 0.25" WC

• R68DD0016 — 0.30" WC

• R68DD0017 — 0.35" WC

• R68DD0018 — 0.40" WC

Technician Notes

• Set Point: 0.20" WC

• Circuit: Normally open — closes on pressure rise

• Function: Proves combustion‑air draft before ignition

• Failure Symptoms:

  • Furnace starts then shuts down

  • Inducer runs but no ignition

  • Error code for pressure switch open

  • Intermittent ignition / short cycling

• Installation Tips:

  • Verify tubing is not cracked or blocked

  • Check inducer wheel for debris

  • Ensure correct port orientation (NO → COM)

  • Do not substitute higher WC switches — will cause lockouts