Electrical Connections; Start-Up Procedure - Modine Manufacturing IFS Installation And Service Manual

INSTALLATION / START-UP PROCEDURE

Electrical Connections

WARNING
1. Disconnect power supply before making wiring
connections to prevent electrical shock and equipment
damage.
2. All appliances must be wired strictly in accordance with
wiring diagram furnished with the appliance. Any wiring
different from the wiring diagram could result in a hazard
to persons and property.
3. Any original factory wiring that requires replacement must
be replaced with wiring material having a temperature
rating of at least 105°C.
4. Ensure that the supply voltage to the appliance, as
indicated on the serial plate, is not 5% greater than rated
voltage.
CAUTION
Ensure that the supply voltage to the appliance, as indicated
on the serial plate, is not 5% less than rated voltage.
1. Installation of wiring must conform with local building
codes, or in the absence of local codes, with the National
Electric Code ANSI/NFPA 70 - Latest Edition. Unit must
be electrically grounded in conformance to this code.
In Canada, wiring must comply with CSA C22.1, Part 1,
Electrical Code.
2. All duct furnaces are provided with a wiring diagram located
on the inside door of the electrical junction box. Refer to
this wiring diagram for all wiring connections. For factory
installed options and field installed accessory wiring, refer
to Set A and Set B on the provided wiring diagram.
3. The power supply to the duct furnace should be protected
with a fused disconnect switch.
4. Refer to the unit serial plate (see Figure 26.1) for the amp
draw of the duct furnace. Size the disconnect switch to
cover the amp draw of the unit. For 460V and 575V units
(Digit 14=F or G) a step down transformer is required.
Units with Digit 15=1 require a 250VA transformer, units
with Digit 15=2 require a 500VA transformer, and units with
Digit 15=3 or 4 require a 1000VA transformer
5. Refer to the unit dimensional drawing on page 18 for the
electrical knockout locations.
12

START-UP PROCEDURE

IMPORTANT
Start-up and adjustment procedures should be performed by a
qualified service agency.
1. Turn off power to the unit at the disconnect switch. Check
that fuses or circuit breakers are in place and sized correctly.
Turn all hand gas valves to the "OFF" position.
2. Check that the supply voltage matches the unit supply
voltage listed on the serial plate. Verify that all wiring is
secure and properly protected. Trace circuits to insure that
the unit has been wired according to the wiring diagram.
3. Check that all electrical and gas connections to the unit are
sealed to prevent air leakage.
4. Check to insure that the venting system is installed and free
from obstructions.
5. Check to see that there are no obstructions to the intake and
discharge of the duct furnace.
6. Perform a visual inspection of the unit to make sure no
damage has occurred during installation.
7. Turn on power to the unit at the disconnect switch. Check to
insure that the voltage between terminals 1 and 2 is 24V.
8. Check the thermostat, ignition control, gas valve, power
exhauster motor, and supply fan blower motor for electrical
operation. If these do not function, recheck the wiring
diagram. Check to insure that none of the Gas Control
Options & Accessories (see page 16) have tripped.
9. Recheck the gas supply pressure at the field installed
manual-shut-off valve. The inlet pressure should be 6"-7"
W.C. on natural gas or 11"-14" W.C. on propane. If inlet
pressure is too high, install an additional pressure regulator
upstream of the combination gas control.
10. Open the field installed manual gas shut-off valve.
11. Open the manual main gas valve on the combination gas
control. Call for heat with the thermostat and allow the
pilot to light. On a call for heat the power exhauster relay
will energize the power exhauster motor. Once the power
exhauster motor reaches full speed, the differential pressure
switch will close before the pilot can light. If the pilot does
not light, purge the pilot line. If air purging is required,
disconnect the pilot line at outlet of pilot valve. In no case
should line be purged into heat exchanger. Check the pilot
flame length (See Pilot Burner Adjustment).
12. Once the pilot has been established, check to make sure
that the main gas valve opens. Check the manifold gas
pressure (See Main Burner Adjustment) and flame length
(See Air Shutter Adjustment) while the circulating air blower
is operating.
13. Check to insure that gas controls sequence properly
(See Control Operating Sequence). Verify if the unit has
any additional control devices and set according to the
instructions in the Gas Controls Options.
14. Once proper operation of the duct furnace has been verified,
remove any jumper wires that were required for testing.
15. Close the electrical compartment door.
16. Replace all exterior panels.
AIR 5-593.9