Eberspächer HYDRONIC B4WSC Technical manual - page 24
24
D
S
GB
F
Function
Depending on the wiring, the heater can be operated
as purely stationary heater or as combined stationary
and auxiliary heater to compensate for an insufficient
output of heat by the vehicle engine.
Stationary heating operation
Switching on
The pilot lamp in the control unit lights up when the
heater is switched on (switch, timer ...). The water pump
starts and after a fixed programme with prerinsing and
preheating, combustion air fan, glow plug and fuel dos-
ing pump set combustion going. Once a stable flame
has formed, the glow plug is switched off by a timer.
Heating operation
Depending on the heat requirement, the heater may
be adjusted to the following levels:
LARGE
SMALL
OFF (control interval)
The temperature thresholds have been fixed pro-
grammed in the electronic control device. If the heat
requirement at level “SMALL” is so low that the cool-
ing water temperature reaches 85
°C, the device
goes into the control interval. This is followed by the
fan continuing to run for approx. 130 seconds. The
pilot lamp also lights up during the control interval
and the water pump continues to run up to the next
controlled start.
Check the following points in the event of faults:
The heater does not start when it is switched on:
Turn-off the heater and then switch it on again,
but not more than twice in succession.
If the heater still does not start:
Is there fuel in the tank?
Has the fuse blown?
Are all electrical lines and connections ok?
Is the combustion-air duct or exhaust-gas duct
blocked?
Conduct a diagnostic test with the JE diagnostic
instrument or the module clock as described in
“Trouble Shooting and Repairs Instructions”
for the HYDRONIC B 4 W SC / B 5 W SC.