Page. 14 of 29
March 2016
Edition 1
PLANAR
5
Heater Components - Repair and Replacement.
5.1 Functions, Removal and Replacement of Glow Plug.
The glow plug provides ignition of fuel mixture during start-up of the heater.
Removal and replacement of glow plug is described in Section 5.
Model
Glow Plug
Operating Voltage
Heater
Operating Voltage
PLANAR-2D
PLANAR-4DM2
PLANAR-44D
9V
12V
18V
24V
PLANAR-8DM
12V
12V
24V
Performance check instruction:
Remove glow plug from the bushing, connect it to CU and start the heater.Note how
glow plug heats up, it should start heating up from the tip to the middle of the heating
element. If the heating element heats up from the middle or from the tip and to the base,
then the glow plug is faulty.
If the glow plug heats up insufficiently, check the voltage outputted by CU to the
glow plug connector. The supply voltage should be ≈9, 12, 18V (depending on the
model). If the voltage readings do not match, replace the CU. If after the replacement of
the CU the heater is operational, the replaced CU is considered failed.
If glow plug is not heating up, check its operation. To do this, disconnect glow plug
connector, connect glow plug to DC power supply with voltage of 9, 12, or 18V
(depending on glow plug model), and after 30 seconds, measure the current.
Current should be between 5.2 to 6.78A (for 9V), from 3 to 5.2A (for 12V) and 2.5
to 3.4 (for 18V). Test time - no more than 90 seconds. Time between tests no less than
180 seconds.
If glow plug does not meet any of the above requirements, it should be replaced.
Glow plug replacement is performed in reverse order. Before installation, check O-rings
for weariness.
If glow plug is OK, check the wires and wire contacts on the control unit. If the
contacts are clean, replace CU and repeat the start. If after replacing CU heater is
operational, then replaced CU is considered failed and must be replaced.
