Proheat X45–School Bus - Manual (Page 36)

Figure 3-23 Option B
1. Make sure the vehicle ignition is switched “OFF.”
2. Locate the PROHEAT thermostat in a central area of the sleeper,
approximately 12" above the bunk. Avoid direct air flow from sleeper fan
ducts. (Figure 3-25)
3. Remove the adjusting knob and face cover. Mark and drill mounting
holes. Mount thermostat using the screws provided. (Figure 3-27)
4. Install relay 1, always between OEM sleeper fan control and OEM
thermostat.
NOTE: The constant power supply wire must be of sufficient size to handle
sleeper fan motor electrical current draw.
5. Route sleeper fan harness from PCM to PROHEAT thermostat. Cut to length.
Connect white wire to terminal 1 of the thermostat.
6. Route a wire from terminal 2 of the thermostat to relay 1 (can be cut from left
over wire harness). Ground the relay using PROHEAT sleeper fan ground
wire (black).
PROHEAT
THERMOSTAT
RELAY 1 STANDARD
12 OR 24/30 AMP
W
HI
TE
BLACK
15 AMP
SLEEPER FAN
HARNESS
PCM
OEM THERMOSTAT
OEM
SLEEPER
HEATER
ASSEMBLY
VEHICLE
FUSE
PANEL
FAN MOTOR
(SINGLE WINDING TYPE)
RESISTOR ASSEMBLY
NOTE: MAY OR MAY NOT BE LOCATED
INSIDE SLEEPER HEATER ASSEMBLY
WHITE
CONSTANT POWER
SOURCE
(i.e. CIGARETTE LIGHTER)
OEM FAN
MOTOR
CONTROL
(2 OR 3 SPEED)
3-15 SECTION 3. INSTALLATION
OPTION B – OEM Heater & Thermostat 3.5.7