Carrier · Furnace

Ht-% Heating at a percent firing rate (59MN7C)

Normal status 59MN7C

What the display is showing

On the 59MN7C modulating furnace the heating status shows Ht followed by the current firing rate in percent while gas heating is active. Nothing is wrong; the figure changes as the control modulates.

Applies to: 59MN7C modulating furnace

Settings for these units

Filter sizes by casing width and filter cabinet · 59SC6A
Filter sizes by casing width and filter cabinet · 59TP6A
Minimum clearances to combustibles · 59TP6A
Minimum clearances to combustibles · 59SC6A
Filter sizes by casing width · 58SB0A/58SB1A
Filter sizes by casing width · Payne PG96VTA

Models that show this code

6 models in 59MN7C

59MN7C060C17--1459MN7C060C21--2059MN7C080C17--1459MN7C080C21--2059MN7C100C21--2259MN7C120C24--22

Other codes on the same units

Fn Component test - blower
HSi Component test - hot surface igniter
HoD Menu: heat blower-off delay
Hpd Heat pump defrost - furnace heating
Ht Heating (59SC6A, 59MN7C menu: heating airflow setting)
Htt Menu: heating thermostat type
PRG Startup display - model program number
PUr Component test - purge (inducer on)

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Source: Carrier 59MN7C installation instructions, Table 17 System Status Display Codes, p.46. Summarized in our own words; check the original manual for your model.

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.