ICP F9MES Series, Service And Technical Support Manual

SERVICE AND TECHNICAL SUPPORT MANUAL

Gas Furnace: F9MES

Specifications  subject to change without notice.

440 04 4900 02

11

Change the blower speed taps as required to maintain proper

temperature rise for Heating and Cooling as described above.

To change blower motor speed selections for heating mode,

remove blower motor lead from control HEAT terminal(s). (See

Figure 4

) Select desired blower motor speed lead(s) from the

other motor leads and relocate it/them to HEAT (heating blower

tap) terminal(s). Reconnect original lead on SPARE terminal.

Adjust Blower Off Delay (Heat Mode)

If desired, the main blower off time delay period may be

lengthened or shortened when operating in the heating mode

to provide greater comfort. For position and location of jumpers

on control center. (See 

Figure 4

 and 

Figure 15

)

The blower off-delay has four adjustable settings from 108 sec

to 216 sec. (See 

Table 4

) To change the blower off delay

setting, move the jumper from one set of pins on the control to

the pins used for the desired blower off delay. Factory blower

off-delay setting is 144 sec.

Table 4

Blower Off Delay Jumper Positions

PINS

1 AND 2

2 AND 3

3 AND 4

4 AND 5

Control

(swtich setting)

90

120

150

180

Time (in sec.)

108

144

180

216

Adjust Cooling Airflow

The cooling airflow can be set from the remaining blower speed

taps. Refer to the Air Delivery Tables in these instructions.

FURNACE OVERHEATING HAZARD

Failure to follow this caution may result in reduced furnace

life.
Recheck temperature rise. It must be within limits specified

on the rating plate. Recommended operation is at the

mid--point of rise range or slightly above.

CAUTION

!

Adjust Thermostat Heat Anticipator

Mechanical thermostat:

 Set thermostat heat anticipator to

match the amp. draw of the electrical components in the R-W

circuit. Accurate amp. draw readings can be obtained at the

wires normally connected to thermostat sub-base terminals, R

and W. The thermostat anticipator should NOT be in the circuit

while measuring current.

1. Remove thermostat from sub-base or from wall.
2. Connect an amp. meter across the R and W sub-base

terminals or R and W wires at wall.

3. Record amp. draw across terminals when furnace is in

low heat and after blower starts.

4. Set heat anticipator on thermostat per thermostat

instructions and install on sub-base or wall.

5. Install blower access door.

Electronic thermostat:

 Set cycle rate for 3 cycles per hr.

Figure 5

Amp. Draw Check with Ammeter

A96316

R Y W G

10 TURNS

THERMOSTAT SUBBASE

TERMINALS WITH

THERMOSTAT REMOVED

(ANITICIPATOR, CLOCK, ETC.,

MUST BE OUT OF CIRCUIT.)

HOOK-AROUND

AMMETER

EXAMPLE: 5.0 AMPS ON AMMETER

10 TURNS AROUND JAWS

=  0.5 AMPS FOR THERMOSTAT

     ANTICIPATOR SETTING

FROM UNIT 24-V

CONTROL TERMINALS

Check Safety Controls

The flame sensor, gas valve, and pressure switch were all

checked in the Start

−

up procedure section as part of normal

operation.

1. Check Main Limit Switch 

This control shuts off combustion system and energizes

air

−

circulating blower motor, if furnace overheats. By

using this method to check the temperature limit control,

it can be established that the limit is functioning properly

and that the limit will operate if there is a restricted

return

−

air supply or motor failure. If the limit control does

not function during this test, the cause must be

determined and corrected.

a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of

cardboard or sheet metal until the limit trips.

c. Unblock return air to permit normal circulation.

d. Burners will re

−

light when furnace cools down.

2. Check Pressure Switch(es) 

This control proves operation of the draft inducer blower.
a. Turn off 220

−

V 50Hz power to furnace.

b. Disconnect inducer motor lead wires from wire

harness.

c. Turn on 220

−

V 50Hz power to furnace.

d. Set thermostat to “call for heat” and wait 1 minute.

When low pressure switch is functioning properly, hot

surface  igniter should 

NOT 

glow and control

diagnostic light flashes a status code 3.  If hot

surface igniter glows when inducer motor is

disconnected, shut down furnace immediately.

e. Determine reason low pressure switch did not

function properly and correct condition.

f. Turn off 220

−

V 50Hz power to furnace.

g. Reconnect inducer motor wires, replace  door, and

turn on 220

−

V 50Hz power.

h. Blower will run for 108 seconds before beginning the

call for heat again.

i. Furnace should ignite normally.