Lennox MERIT ML180UH User Manual

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Troubleshooting: Continuous Fan Sequence of Operation
CONTINUOUS HEAT SPEED FAN SEQUENCE OF OPERATION
LED: SLOW FLASH RATE REMAINS
UNCHANGED THROUGHOUT SEQUENCE.
MANUAL FAN SELECTION MADE AT THERMOSTAT.
CONTROL (G) ENERGIZES SYSTEM FAN AT HEAT
SPEED. EAC TERMINAL IS ENERGIZED.
THERMOSTAT CALLS FOR HEAT (W).
THERMOSTAT CALLS FOR COOLING.
THERMOSTAT OPENS.
SYSTEM FAN SWITCHED TO COOL SPEED.
EAC TERM. REMAINS ON.
THERMOSTAT OPENS.
MANUAL FAN SELECTION MADE AT THERMOSTAT.
CONTROL (G) ENERGIZES SYSTEM FAN AT HEAT
SPEED. EAC TERM. ENERGIZED.
NO
YES
YES
NO
HUM TERM. ENERGIZES
WITH COMB. AIR INDUCER.
SYSTEM FAN REMAINS ON
HEATING SPEED.
SYSTEM FAN REMAINS ON
HEATING SPEED.
HUM TERM. DE−ENERGIZES
WITH COMB. AIR INDUCER

Lennox MERIT ML180UH Specifications

General

AFUE	80%
Blower Motor	PSC
Gas Valve	Single-stage
Ignition System	Hot surface ignition
Fuel Type	Natural gas or Propane
Heating Capacity	44, 000-132, 000 BTU/h
Warranty	5-Year Limited Warranty on covered components