Installations Instructions

ManualsBrandsGoodman ManualsCooling & Air Quality3.5 Ton 16 SEER 97% AFUE 80,000 BTU Gas Furnace and Air Conditioner System - Upflow

FURNACE CONTROL BOARD

The furnace control board is an electronic device which, if a

potential safety concern is detected, will take the necessary

precautions and provide diagnostic information through an

LED display.

PRIMARY LIMIT

The primary limit control is located on the partition panel and

monitors heat exchanger compartment temperatures. It is a

normally-closed (electrically), automatic reset, temperature-

activated sensor. The limit guards against overheating as a

result of insufficient conditioned air passing over the heat

exchanger.

AUXILIARY LIMIT

The auxiliary limit controls are located on or near the circula-

tor blower and monitors blower compartment temperatures.

They are a normally-closed (electrically), auto-reset sensors.

These limits guard against overheating as a result of insuffi-

cient conditioned air passing over the heat exchanger.

ROLLOUT LIMIT

The rollout limit controls are mounted on the burner/mani-

fold assembly and monitor the burner flame. They are nor-

mally-closed (electrically), manual-reset sensors. These lim-

its guard against burner flames not being properly drawn into

the heat exchanger.

• Furnace circulator blower and outdoor cooling unit run

their appropriate speeds, integrated control module

monitors safety circuits continuously.

• R and Y1/G or Y2/G thermostat contacts open,

completing the call for cool.

• Outdoor fan and compressor are de-energized.

• Circulator blower continues running during a cool off

delay period. The OFF delay time and airflow level are

determined by the selected ramping profile.

• Electronic air cleaner terminal and circulator blower

are de-energized.

• Furnace awaits next call from thermostat.

FAN ONLY MODE

The normal operational sequence in fan only mode is as fol-

lows:

• R and G thermostat contacts close, initiating a call for

fan.

• Integrated control module performs safety circuit

checks.

• Circulator blower is energized on continuous fan speed

(25%, 50%, 75% or 100% DIP switch selectable when

using a conventional thermostat). Electronic air

cleaner terminal is energized.

• The furnace control board HUM dry contacts close.

• Circulator blower runs, integrated control module

monitors safety circuits continuously.

• R and G thermostat contacts open, completing the call for

fan.

• Circulator blower is de-energized. Electronic air cleaner

terminal is de-energized.

• Furnace awaits next call from thermostat.

PERATIONAL

HECKS

The burner flames should be inspected with the burner com-

partment door installed. Flames should be stable, quiet, soft,

and blue (dust may cause orange tips but they must not be

yellow). Flames should extend directly outward from the burn-

ers without curling, floating, or lifting off. Flames must not

impinge on the sides of the heat exchanger firing tubes.

Check the

Burner Flames for:

1. Stable, soft and blue.

2. Not curling, floating

or lifting off.

Burner Flame

Figure 54

AFETY

IRCUIT

ESCRIPTION

A number of safety circuits are employed to ensure safe and

proper furnace operation. These circuits serve to control any

potential safety hazards and serve as inputs in the monitoring

and diagnosis of abnormal function. These circuits are con-

tinuously monitored during furnace operation by the integrated

control module.