Amana AMVC960803BN Error Code EE3: Open High Limit Switch

What Does Code EE3 Mean?

The primary high-limit switch is a temperature safety mounted near the heat exchanger of the AMVC960803BN. When enough conditioned air moves across the heat exchanger, it stays within a safe temperature band. If airflow drops, heat builds up and the limit opens, which the Integrated Control Module reports as EE3 on its 7-segment display and shuts the burners down. You will typically see the circulator blower keep running on its own to pull that trapped heat out of the cabinet.

Because this is a variable-speed, two-stage furnace, it moves a lot of air on high fire, and anything that chokes that airflow — most often a clogged filter, but also closed or blocked registers, crushed or undersized ductwork, or a blower running too slow — can push the heat exchanger past the limit setpoint. The manual lists blocked filters, restrictive ductwork, improper blower speed, or a failed blower motor as the causes.

EE3 is closely related to EEd, the auxiliary limit switch, but the two watch different spots: EE3 is the primary limit at the heat exchanger, while EEd is an auxiliary limit in the blower compartment. It also shares a family with E11, the flame rollout switch, which trips when heat or flame escapes the burner area rather than from an airflow shortage. The single homeowner-safe cause here is restricted airflow from a dirty filter, so that is all the DIY steps below cover — everything deeper is a technician's job.

What You'll Notice

• The blower keeps running continuously even though there is no warm air
• The furnace produces little or no heat after briefly firing
• The 7-segment display shows EE3
• The air filter is visibly gray, matted, or clogged when you pull it
• The furnace short-cycles: it lights, warms up, then shuts the burners off

Common Causes

How This Is Diagnosed

The cause is isolated from the easiest airflow restriction outward. First the filter is checked and replaced if dirty, and all supply and return grilles are confirmed open and unobstructed. If airflow is still short with a clean filter, a technician measures temperature rise and static pressure across the furnace, inspects the ductwork for restrictions or a closed damper, and verifies the blower is turning at the correct programmed speed. Only after airflow is confirmed adequate do they test the limit switch and its wiring for a stuck-open contact.

How to Fix It: Restore Airflow by Checking the Filter

What You'll Need

• New furnace air filter (correct size) 🛒 Find at FiltersFast · 🛒 Find at Amazon
• Flashlight

Steps

1. Turn off power at the breaker or furnace switch and shut off the gas supply Switch the furnace breaker (or disconnect switch) to OFF and turn the manual gas shutoff valve to the closed position (handle perpendicular to the pipe). If you smell gas at any time, leave immediately and call your gas company from outside.
2. Remove and inspect the air filter Locate the filter in the return duct or the furnace's filter slot. Hold it up to a light. If you cannot see light through it, or it is gray and matted, it is restricting airflow enough to trip the high limit.
3. Install a clean filter of the correct size Slide in a new filter of the same dimensions, with the airflow arrow pointing toward the furnace. Avoid overly dense high-MERV filters that your system cannot pull air through, as they can cause this exact overheating condition.
4. Open and clear all vents and returns Walk the house and make sure supply registers are open and not blocked by furniture or rugs, and that return grilles are unobstructed. Closing off too many rooms starves the blower of return air.
5. Restore gas and power, then let it reset Reseat the panel, open the gas valve (handle parallel to the pipe), and switch the breaker back ON. The high limit resets on its own once the heat exchanger cools. Set the thermostat to call for heat.

When to Call a Professional

Contact a licensed HVAC technician if:

• EE3 returns after the filter is replaced and all vents are open
• The blower runs but moves noticeably weak airflow
• The furnace short-cycles on overheating within a few minutes of lighting
• You hear the blower struggling, surging, or not starting
• You suspect crushed, undersized, or blocked ductwork

✓ Verified against manufacturer service manual — March 2026