Rheem RGRA-07EMAES Error Code 4 Blinks: Pressure Switch Circuit Closed

What Does Code 4 Blinks Mean?

Four blinks of the green STATUS LED on the Rheem RGRA-07EMAES is the UTEC 1012-925 Integrated Furnace Control (IFC) reporting that the pressure switch circuit is closed at a time when it should be open. Before it starts the ignition sequence, the board checks that the pressure switch is open with the induced-draft motor off. If the contacts are already made, the IFC cannot trust the switch to prove draft later in the cycle, so it flags the fault and refuses to fire.

This is the mirror image of the 2-blink code. Two blinks means the switch failed to close when draft should have proven; four blinks means the switch failed to open when there is no draft. On this single-stage board there is one pressure switch performing both proofs, so the control watches it move in both directions as a safety check. A switch stuck closed defeats that logic and is treated as unsafe.

The usual reasons are a pressure switch whose contacts have welded or stuck closed, water or condensate trapped in the switch or its sensing hose bridging the contacts, or a wiring short across the switch terminals. None of these are homeowner-serviceable — they require metering the switch and inspecting the draft-proving wiring — so this code routes to a technician.

What You'll Notice

• No heat, and the green STATUS LED repeats a four-blink pattern
• The furnace will not begin its ignition sequence even though it has power
• The inducer may not start normally because the control has already flagged the switch as faulty
• The problem can appear after high-condensate operation or if water has collected in the switch hose
• The fault persists through power resets, unlike a transient vent blockage

Common Causes

How This Is Diagnosed

A technician first confirms the pressure switch is genuinely closed at rest by metering it with the inducer off; the switch should read open. They then trace the sensing hose for trapped water or condensate, since moisture can bridge the contacts and mimic a stuck switch, and they inspect the switch wiring for a short across the terminals that would keep the circuit made.

If the switch is truly stuck closed and the hose and wiring are clear, the switch itself is replaced with the correct part for this model. Because the diagnosis involves electrical metering of a safety interlock and the draft-proving circuit, it is informational here and not a homeowner repair.

When to Call a Professional

This code involves components that are not homeowner-serviceable, so have a licensed HVAC technician diagnose and repair it. Keep in mind:

• The green STATUS LED shows four blinks and the fault stays after cycling furnace power
• You suspect water or condensate has collected in the pressure-switch hose or switch body
• The furnace recently had venting or condensate-drain problems that could have flooded the switch
• The four-blink code alternates with two-blink faults, suggesting an intermittent switch
• You are not equipped to safely meter a pressure switch and its wiring

✓ Verified against manufacturer service manual — March 2026