Electrical; Furnace Operation; Field Supplied And Installed Optional Accessories; Electronic Air Cleaner - Fedders FV95A054 Installating And Operation Manual

Electrical

WARNING
DISCONNECT THE ELECTRICAL POWER SUPPLY TO THE
FURNACE BEFORE ATTEMPTING THIS MAINTENANCE
PROCEDURE. FAILURE
ELECTRICAL SHOCK RESULTING IN PERSONAL INJURY OR
LOSS OF LIFE.
All electrical connections should be examined to ensure that
they are tight and corrosion free. Repair any connections
that have become loose or corroded.
CAUTION
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and
dangerous operation.
Always verify proper operation after servicing.

Furnace Operation

The furnace should be cycled during the annual inspection
and servicing to:
1. Test all safety related controls.
2. Determine that the temperature rise falls within the
range shown on the appliance rating plate.
3. Ensure that the burner ignition is smooth and that the
flames are smooth soft blue, and not impinging on the
heat exchanger.
FIELD SUPPLIED AND INSTALLED OPTIONAL
ACCESSORIES

Electronic Air Cleaner

The integrated furnace control has provisions to supply
power and control an electronic air cleaner rated at 120vac,
1.0 amp max.
Line voltage for an electronic air cleaner may be picked up
from the "EAC-N". 120 volt power will be available at these
terminals whenever the circulating fan is operating in the
heating or cooling modes.
Humidifiers/ Electronic Air Cleaners
The integrated furnace control has provisions to supply
power and to control a line voltage humidifier or the
primary of a 120 / 24 volt humidifier step down transformer,
rated at 120vac, 1.0 amp max.
Line voltage for a humidifier may be picked up from the
"HUM-H" terminal and from the "HUM-N" terminal. 120
volt power will be available at these terminals whenever
the circulating fan is operating in the heating mode.
IMPORTANT
All HUM (humidifier) and EAC (electronic air cleaner)
terminals are 120v. Do not directly connect 24v
equipment to them.
IMPORTANT
All furnace and furnace accessory wiring shall conform
to the temperature limitations of 63°F (35°C) rise.
TO DO SO CAN CAUSE
ALL WIRING INSIDE THE FURNACE MUST HAVE A
MINIMUM TEMPERATURE RATING OF 105C.

Troubleshooting

Page 41, Table 9, Page 42, Table 10 and Figure (trouble shooting)
will aid in trouble shooting.
The controller ignites the furnace in low heat and high
inducer (only the low pressure switch is required to make)
and after a 60 second warm-up period adjusts either the gas
or inducer to heat demand. With the single stage
thermostat option, there is a selectable low heat period
before high heat. If there is a problem with high or low
h eat the UTEC 1170-25 controller will attempt to continue
to supply heat in one of three alternate firing scenarios.
Scenario one:
• if, after the warm-up period and the low heat period with
a single stage thermostat, or with a two stage T-stat the
demand for heat is high and the high heat pressure switch
fails to make, the furnace will run in low gas and high
inducer until the high pressure switch makes.
The second scenario;
If the low heat fails after the warm-up period, the
controller will wait 3 minutes before ignition retrial and
then after the warm-up period go to high heat. Most likely
the failure of the low heat is temporary and may be due to
a combination of high wind and long vent length and low
voltage. If there is a blocked drain the furnace will not turn
the igniter or gas on. If there is an air trap in the heat
exchanger drain tube the furnace will cycle and flash code
for pressure switch failed to close.
The third scenario;
If the low heat fails after the warm-up period, and when
the next trial for high fails to make the high pressure
switch, the unit will stay in low heat and high inducer (as
long as the low pressure switch is made). If, during this
period, the high pressure switch makes, the gas valve will
switch to high. A loss of high pressure switch will force the
gas valve to low. If there is ice in the vent the continuous
heat should free it. Note: When the inducer is in high and
the gas low the flame noise sounds deceptively like high
heat.
The fourth scenario:
If there is a demand for high heat (low heat firing period is
finished) and during the trial for ignition the high pressure
switch does not pull in the controller will continue in low
heat and make a retrial for high every 5 or 10 minutes.
39
WARNING