Troubleshooting: Heating Sequence of Operation (Continued)

HEATING SEQUENCE OF OPERATION

CONTINUED

THERMOSTAT CALLS FOR HEAT.

STATUS LED −− HEARTBEAT.

SEE BOX A.

FLAME SIGNAL ABOVE

(u1.40 microamps)

YES

YES

SINGLE−STAGE THERMOSTAT MODE (DIP SWITCH SET AT

YES

START SECOND−STAGE RECOGNITION ON DELAY (10 OR 15 MINUTES).

STATUS LED −− HEARTBEAT

ROLLOUT SWITCHES CLOSED?

YES

FIRST−STAGE (LOW FIRE)

PRESSURE SWITCH CLOSED?

NO

LOW FLAME SIGNAL

(Does not affect control operation) STATUS ERROR CODE 1 + 2.

TWO STAGE THERMOSTAT MODE (DIP SWITCH SET AT

YES

 

 

 

 

45−SECOND INDOOR BLOWER ON DELAY BEGINS.

 

 

 

 

 

STATUS LED −− HEARTBEAT.

 

 

 

 

 

YES

 

 

 

YES

 

 

 

NO

PRIMARY & SECONDARY LIMIT SWITCHES

 

 

 

 

 

CLOSED?

 

NO

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

INDOOR BLOWER ON.

 

 

 

 

 

 

 

YES

STATUS ERROR CODE 5 + 1. SEQUENCE HOLDS

 

 

UNTIL ROLLOUT SWITCH IS RESET AND MAIN

 

 

 

 

 

 

 

 

 

 

POWER IS INTERRUPTED OR THERMOSTAT

 

 

 

 

 

IS CYCLED OFF/ON FOR 3 SECOND MINIMUM.

 

YES

NO

NO

FIRST−STAGE HEAT DEMAND SATISFIED?

YES

GAS VALVE OFF, COMBUSTION AIR INDUCER

OFF FOLLOWING POST PURGE.

INDOOR BLOWER OFF WITH DELAY

STATUS LED −− PULSE

SECOND−STAGE HEAT DEMAND.

SECOND−STAGE HEAT DEMAND REQUIRED?

YES

SECOND STAGE PRESSURE SWITCH CLOSED?

ABNORMAL FLASH CODE.

NOTE − IF SECOND−STAGE PRESSURE SWITCH

WAS ORIGINALLY FOUND CLOSED,

ABNORMAL CODE WILL FLASH.

NO

YES

SECOND−STAGE 30−SECOND DELAY ON BEGINS.

STATUS LED −− HEARTBEAT.

YES

SECOND−STAGE COMBUSTION AIR INDUCER ON. SECOND−STAGE GAS VALVE ON. HIGH HEAT INDOOR BLOWER SPEED ON. STATUS LED −− HEARTBEAT.

YES

SECOND−STAGE PRESSURE SWITCH CLOSED

IN LESS THAN TEN (10) SECONDS?

STATUS LED −− HEARTBEAT

YES

CONTINUED ON NEXT PAGE

GAS VALVE OFF, COMBUSTION AIR INDUCER OFF,

 

INDOOR BLOWER ON.

 

STATUS ERROR CODE 3 + 1.

 

 

 

YES

HAS PRIMARY OR SECONDARY LIMIT

SWITCH CLOSED WITHIN 3 MINUTES?

 

(Indoor blower on low speed during 3−minute period)

 

 

 

NO

 

 

 

 

 

LIMIT SWITCH WATCHGUARD MODE.

 

GAS VALVE OFF, COMBUSTION AIR INDUCER OFF,

 

INDOOR BLOWER OFF WITH DELAY.

YES

STATUS ERROR CODE 4 + 5

 

IS 60−MINUTE RESET PERIOD COMPLETE?

 

GAS VALVE OFF. COMBUSTION AIR INDUCER ON. INDOOR BLOWER OFF AFTER DELAY.

STATUS ERROR CODE 2 + 3. CONTROL RESTARTS YES IGNITION SEQUENCE IF PRESSURE SWITCH

CLOSES WITHIN 2−1/2 MINUTES.

 

SECOND−STAGE PRESSURE SWITCH CLOSED

NO

 

AT BEGINNING OF HEAT DEMAND?

 

 

 

STATUS ERROR CODE 2 + 6.

 

 

 

 

 

SECOND STAGE HEAT DEMAND

 

 

STATUS LED −− HEARTBEAT.

 

 

NO

 

 

RETURNS TO FIRST−STAGE HEAT MODE WHICH

 

 

CONTINUES UNTIL SECOND−STAGE PRESSURE

 

 

SWITCH CAN BE PROVEN or HEAT DEMAND IS

 

 

SATISFIED. FIVE (5) MINUTE WAIT PERIOD

 

NO

INITIATED BEFORE RETRY. WERE 5 ATTEMPTS

 

MADE FOR SECOND−STAGE HEAT?

 

 

YES

 

 

 

CONTINUES FIRST−STAGE HEATING DEMAND.

 

 

WILL NOT REATTEMPT SECOND−STAGE

 

 

HEATING DEMAND.

 

 

STATUS ERROR CODE 2 + 5.

 

Page 59

Page 59
Image 59
Lennox International Inc G61MP Series Units, Gas Units installation instructions U1.40 microamps

G61MP Series Units, Gas Units specifications

Lennox International Inc. has established itself as a leader in the heating and cooling industry, and its G61MP Series Gas Units stand as a testament to the company's commitment to innovation and energy efficiency. These gas units are specifically designed for residential applications and are recognized for their reliability, performance, and advanced technology.

One of the main features of the G61MP Series is its variable speed motor, which offers significantly enhanced comfort over traditional single-stage gas units. This technology allows for precise temperature control and improved humidity management. By adjusting its speed according to the heating demand, the unit minimizes temperature fluctuations, leading to a more consistent indoor climate.

Another notable characteristic of the G61MP Series is its ECM blower motor, which operates quietly and efficiently. This motor not only reduces energy consumption but also enhances the overall comfort of the home by providing a steady flow of warm air without the disruptive noise often associated with traditional gas units.

The G61MP Series units are designed with a focus on energy efficiency, boasting an impressive Annual Fuel Utilization Efficiency (AFUE) rating. This rating indicates that these units convert a significant portion of the fuel they consume into usable heat, resulting in lower energy bills for homeowners. The units are equipped with a modulating gas valve that further optimizes fuel usage by adjusting the gas flow according to the heating needs of the home.

Safety is a paramount consideration in the design of the G61MP Series. These units are built with advanced safety features, including a self-diagnostic control system that continuously monitors the unit’s performance. This system alerts homeowners to any potential issues, allowing for proactive maintenance and ensuring the longevity of the equipment.

The G61MP Series is also designed for ease of installation and servicing. Its compact design allows for flexible placement in various home environments, while the user-friendly access panels simplify routine maintenance tasks.

In conclusion, Lennox International Inc.'s G61MP Series Gas Units deliver a combination of advanced technology, energy efficiency, and reliability, making them an excellent choice for homeowners looking to enhance their heating systems. With features designed to maximize comfort, minimize energy costs, and ensure safety, these units represent a significant advancement in residential heating solutions.