HVACopediaKeepRite · Furnace · Heating
Single-stage 95% furnace: heating cycle and blower delays
What happens, in order
- After flame is proven, blower starts at heat speed 25 s after the gas valve opens; air cleaner terminal comes on with the blower
- Thermostat satisfied gas valve closes and humidifier terminal drops
- Inducer runs a 15 s post-purge, then stops
- Blower keeps running for the heat-off delay (90, 120, 150 or 180 s), factory 120 s
Timings and thresholds
| Item | Value |
|---|---|
| Blower-on delay | 25 s |
| Inducer post-purge | 15 s |
| Heat-off delay options | 90 / 120 / 150 / 180 s |
| Heat-off delay factory | 120 s |
Applies to: KeepRite / ICP (F-G)9MXE single-stage 95% furnace (KeepRite G9MXE)
Models
More KeepRite furnace sequences
- Modulating 95% furnace: ignition sequence and retries · Ignition
- Single- and two-stage 95% furnace: ignition sequence and retries · Ignition
- Modulating 95% furnace: adaptive heating, staging and blower delays · Heating
- Two-stage 95% furnace: low/high heat, staging and blower delays · Heating
- Furnace blower with outdoor A/C: cooling, dehumidify and continuous fan · Cooling
- Furnace used with a heat pump (dual fuel blower timing) · Other
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Source: KeepRite/ICP (F-G)9MXE service manual 440 04 4311 09, Sequence of Operation. Written in our own words; timings can differ by model and software version, so check the manual for your exact unit.
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