Cooling Mode; Operational Checks; Fan Only Mode; Safety Circuit Description - Amana xMVM97 series Installation Instructions Manual

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 (30) seconds and then switch to the low heating
speed for the balance of the heat off delay period (60,
90, 120 or 150 seconds).
•
Circulator blower and electronic air cleaner terminal 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.
C M
OOLING ODE
The normal operational sequence in cooling mode is as follows:
•
R and Y1/G or Y2/G thermostat contacts close, initiating
a call for cool.
•
Integrated control module performs safety circuit checks.
•
Outdoor fan and compressor are energized to their
appropriate speed.
•
Circulator blower is energized on the appropriate cool
speed at the level and time determined by the selected
ramping profile. Electronic air cleaner terminal is
energized with circulator blower.
•
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.
F O M
AN NLY ODE
The normal operational sequence in fan only mode is as follows:
•
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.
O C
PERATIONAL HECKS
The burner flames should be inspected with the burner compart-
ment 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 burners without
curling, floating, or lifting off. Flames must not impinge on the
sides of the heat exchanger firing tubes.
S C D
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 continu-
ously monitored during furnace operation by the integrated con-
trol module.
F C B
URNACE ONTROL OARD
The furnace control board is an electronic device which, if a
potential safety concern is detected, will take the necessary pre-
cautions and provide diagnostic information through an LED dis-
play.
P L
RIMARY IMIT
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-ac-
tivated sensor. The limit guards against overheating as a result
of insufficient conditioned air passing over the heat exchanger.
A L
UXILIARY IMIT
The auxiliary limit controls are located on or near the circulator
blower and monitors blower compartment temperatures. They
are a normally-closed (electrically), auto-reset sensors. These
limits guard against overheating as a result of insufficient
conditioned air passing over the heat exchanger.
R L
OLLOUT IMIT
The rollout limit controls are mounted on the burner/manifold
assembly and monitor the burner flame. They are normally-
closed (electrically), manual-reset sensors. These limits guard
against burner flames not being properly drawn into the heat
exchanger.
45
Check the
Burner Flames for:
1. Stable, soft and blue.
2. Not curling, floating
or lifting off.
Burner Flame
Figure 53