Goodman Mfg AMV8 instruction manual XI. Sequence of Operation Integrated Ignition Control

FILTERS - READ THIS SECTION BEFORE INSTALLING THE RETURN AIR DUCTWORK

Filters must be used with this furnace. Discuss filter maintenance with the building owner. Filters do not ship with this furnace, but must be provided by the installer. Filters must comply with UL900 or CAN/ULCS111 standards. If the furnace is installed without filters, the warranty will be voided.

NOTE: An undersized opening will cause reduced airflow.

For air delivery of less than 1800 CFM, use a one side or bottom return. For air delivery of 1800 CFM or higher, use either two- sided returns or a one-sided return with a bottom return. Refer to Minimum Filter Area tables at the end of this manual to determine filter area requirements.

UPRIGHT INSTALLATIONS

Depending on the installation and/or customer preference, differing filter arrangements can be applied. Filters can be installed in the central return register or a side panel external filter rack kit (upflows), or the ductwork above a counterflow furnace. As an alternative, a media air filter or electronic air cleaner can be used as the requested filter. The following figures show possible filter locations.

CIRCULATION AIR FILTERS

One of the most common causes of a problem in a forced air heating system is a blocked or dirty filter. Circulating air filters must be inspected monthly for dirt accumulation and replaced if necessary. Failure to maintain clean filters can cause premature heat exchanger failure.

A new home may require more frequent replacement until all construction dust and dirt is removed. Circulating air filters are to be installed in the return air duct external to the furnace cabinet.

WARNING

BEFORE PERFORMING ANY SERVICE ON THIS FURANCE, DISCONNECT THE MAIN POWER SUPPLY. DO NOT OPERATE THE FURNACE WITHOUT CIRCULATIONG AIR FILTERS IN PLACE.

MINIMUM FILTER SIZES

FURNACE INPUT	FILTER SIZE	TYPE
45M	160 in2	permanent
68M	241 in2	permanent
90M	320 in2	permanent
115M	400 in2	permanent
135M	370 in2	permanent
45M	320 in2	disposable
68M	483 in2	disposable
90M	640 in2	disposable
115M	800 in2	disposable
135M	738 in2	disposable

PERMANENT NOMINAL 600 F.P.M.

DISPOSABLE NOMINAL 300 F.P.M.

HORIZONTAL INSTALLATIONS

Filters must be installed in either the central return register or in the return air duct work.

XI. SEQUENCE OF OPERATION

(INTEGRATED IGNITION CONTROL)

Refer to Timing Charts for sequencing.

The normal power up sequence is as follows:

•115 VAC power applied to furnace.

•Integrated control module performs internal checks.

•Integrated control module flashes LED lights.

•Integrated control module monitors safety circuits continuously.

•Furnace awaits call from thermostat.

NORMAL HEATING SEQUENCE

•R and W1 (or R and W1/W2) thermostat contacts close, initiating a call for heat.

•Integrated control module performs safety circuit checks.

•Induced draft blower is energized on high speed for a 15- second prepurge. Humidifier terminals are energized with induced draft blower.

•Induced draft blower steps to low speed following prepurge. Low stage pressure switch contacts are closed.

•Igniter warm up begins upon step to low speed and presence of closed low stage pressure switch contacts.

•Gas valve opens at end of igniter warm up period, delivering gas to burners and establishing flame.

•Integrated control module monitors flame presence. Gas valve will remain open only if flame is sensed.

•If the thermostat call is for low heat, gas valve and induced draft blower will continue on low stage. If the call is for high heat, the gas valve and induced draft blower will change to high stage.

•Circulator blower is energized on the appropriate heat speed following a fixed thirty second blower on delay. The circulator blower requires 30 seconds to ramp up to full speed. Electronic air cleaner terminals are energized with circulator blower.

•Furnace is now operating on the specified stage called for by the two-stage thermostat.

•Furnace runs, integrated control module monitors safety circuits continuously.

•If the two-stage thermostat changes the call from low heat to high heat, the integrated control module will immediately switch the induced draft blower, gas valve, and circulator blower to their high stage settings.

•If the two-stage thermostat changes the call from high heat to low heat, the control will immediately switch the induced draft blower and gas valve to their low stage settings. The circulator blower will remain on high heating speed for thirty seconds before switching to the low heat circulating speed.

•R and W1 (or R and W1/W2) thermostat contacts open, completing the call for heat.

•Gas valve closes, extinguishing flame.

•Induced draft blower is de-energized following a fifteen second post purge. Humidifier terminals are de-energized.

•Circulator blower continues running for the selected heat off delay period (90, 120, 150 or 180 seconds). The speed run during this period depends on the last heat call provided by the thermostat.

If the last call for heat was a call for high heat, the air circulating motor will run on the high heating speed for thirty seconds and then switch to the low heating speed for the balance of the heat off delay period

•Electronic air cleaner terminals is de-energized

•Circulator blower ramps down to OFF during the 30 seconds following the heat off delay period.

•Furnace awaits next call from thermostat.

NORMAL COOLING SEQUENCE - INTEGRATED IGNITION CON- TROL

•R and YLO/G or Y/G thermostat contacts close, initiating a call for cool.

IO-247A 21 12/04