Options - Modine Manufacturing PDP Installation And Service Manual

oPtions

figure 13.1 - factory mounted option location
➂
➁
➆ ➄
All units include the standard (STD) features. The unit must be
reviewed to determine the optional (OPT) features that may
have been supplied with the unit.
(1) Gas valve
a) single stage Gas valve - (std)
The main gas valve is factory installed on the unit heater gas
train. The main gas valve provides the pilot, regulator, main
gas, and manual shutoff functions. For additional information,
see the supplier literature included with the unit.
b) two stage Gas valve - (oPt)
The two-stage gas valve is factory installed on the unit heater
gas train. The two stage gas valve provides the pilot, regulator,
main gas (100% and 50% fire), and manual shutoff functions. For
additional information, see the supplier literature included with
the unit.
c) mechanical modulation - (oPt)
Mechanical modulation utilizes a main gas valve as well as a
mechanical modulating gas valve (not shown). The mechanical
modulating valve includes a hydrostatic sensing bulb that is
temporarily affixed to the side of gas train to be field installed
in ductwork. The discharge air temperature is field set by the
control dial on the modulating gas valve. Refer to Control
Operating Sequence - Mechanical Modulating Gas Controls for
set point temperatures.
figure 13. - mechanical modulation sensing Bulb
Hydrostatic Sensing Bulb
Hydrostatic Sensing Bulb
➇
➃
➀
Gas Control knob
Gas Control knob
NO OFF
Control Dial
Control Dial
➈
⑥
() ignition controller - (oPt)
The ignition controller is factory installed on the back of the unit
heater with the spark igniter and sensor located on the burner.
For both natural and propane gas units, the ignition controller
is 100% shut-off with continuous retry. On a call for heat, the
system will attempt to light the pilot for 70 seconds. If the pilot
is not sensed for any reason, the ignition control will wait for
approximately six minutes with the combination gas control
closed and no spark. After six minutes, the cycle will begin
again. After three cycles, some ignition controllers lockout for
approximately one hour before the cycle begins again. This will
continue indefinitely until the pilot flame is sensed or power is
interrupted to the system.
(3) time delay relay - (std on all but mech. mod.)
The time delay relay is factory installed in electrical junction
box. The time delay relay allows the gas controls to operate for
approximately 30 to 90 seconds before the blower starts. This
allows the heat exchanger a warm up period so that the initial
delivered air is not cool. The time delay relay also keeps the
motor running for approximately 30 - 90 seconds after the call
for heat has been satisfied to remove the residual heat from the
heat exchanger. For single-phase units below 2 Hp, the time
delay relay controls the motor directly. For single-phase units 2
Hp and greater and all three phase units, the time delay relay
controls the motor starter.
note: Mechanical modulation units are used on make-up
air only and do not require time delay relays. Therefore,
mechanical modulation units are not supplied with time delay
relays.
(4) low voltage terminal Board - (std)
The low voltage terminal board is located in electrical junction
box. The terminal board is labeled to match the electrical
wiring diagram provided with the unit. All low voltage field
wiring connections should be made to the exposed side of the
terminal board (exterior of electrical junction box) to prevent
miswiring by modifying the factory wiring which is inside the
electrical junction box.
6-580.4 13