Proheat M80 - Manual (Page 28)

PROHEAT G-I PCM SERVICE MANUAL 2-7
CAUTION
Always ensure that the PROHEAT is allowed to Cool Down (Purge) for a full 3
minutes. If the power is shut off without a proper Cool Down (Purge) during
Full Output, DAMAGE TO THE HEATER MAY OCCUR.
The PROHEAT will continue in Full Output until the coolant temperature reaches
185°F (85°C) at the PROHEAT outlet Temperature Sensor. The PROHEAT closes
the Fuel Shut-off Valve and goes into Cool Down (Purge).
The Motor and Coolant Pump continue to operate for three minutes. After three
minutes, the Motor and Coolant Pump stop and the PROHEAT enters
Supplemental Standby (coolant pump off). The PROHEAT will Cool Down
(Purge) for three reasons:
• Coolant reaches 185°F (85°C).
• A fault is detected. Go to Section 4.0 Troubleshooting and Repair, page 4-1.
• The PROHEAT is operating in Ignition or Full Output when it is switched off.
The Coolant Pump is “OFF” but the G-I PCM continuously monitors the coolant
temperature. If the coolant temperature drops below 160°F (71°C), the G-I PCM
will enter the cycle starting at Pre-run. The PROHEAT will continue to repeat
Steps 2 to 6 until it is switched “OFF.”
If the coolant pump is requested on via the coolant pump input (analog or
CAN) the PROHEAT enters Standby (coolant pump on). If the coolant
temperature drops below 160°F (71°C) the PROHEAT will move directly to
Pre-check (step 3).
If the coolant pump is no longer requested on via the coolant pump input (analog
or CAN) the PROHEAT enters Supplemental Standby (coolant pump off).
The ON/OFF switch lamp, timer lamp or OEM indicator (installation options)
will turn off.
If the PROHEAT is in Full Output, it will Purge first and then shut “OFF”.
If the PROHEAT is in Standby, it will shut “OFF” immediately.
7. Supplemental
Standby
(Coolant pump off)
8. Supplemental
Mode Signal
Removed
(Engine off)
7A. Standby
(Coolant pump on)
9. Fault Shut
Down
5. Full Output
6. Cool Down (Purge)
If the PROHEAT diagnostics sense a system or component fault, the
PROHEAT will shut down all components and flash a fault code(s) which best
represents the conditions. To reset the PROHEAT, it must be switched off
and then on again.
NOTE: Damage may occur it the fault codes are ignored and the PROHEAT is
repeatedly switched off and on without addressing the problem.
NOTICE
There is no time delay to shut off the PROHEAT in Supplemental Mode.