Rheem · Furnace

66 Blower overspeed (BLOWER OVRSPEED)

Medium severity RGPE/RGLE

What the control is telling you

ECM blower running faster than expected - usually means very low static (missing panel/filter) or very high restriction.

Applies to: RGPE/RGLE 2-stage 80+

Likely causes

Blower door or filter/panels missing
Duct disconnected
Severe restriction

Test and repair steps

Confirm blower door and all panels are in place.
Check filter and ducts for disconnection or blockage.
Check blower wheel.
Verify on unit check airflow (decimal blink = 1 per 100 CFM) against expected.

Settings for these units

Filter sizes as shipped, upflow (Table 19) · RGPE/RGLE
Reduced clearance to combustibles (Fig. 3 and 4) · RGPE/RGLE

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Source: RGPE/RGLE: Table 16 p.49 / Table 20. Summarized in our own words; check the original manual for your model.

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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.