I’m wondering if anybody has ever repaired a faulty night heater? Mine has started playing up, it fires up normally, blows out a normal amount of hot air for around 10 minutes, then enters shutdown mode and stops. Turning it off and on again repeats this cycle.
I’ve checked the intake, which is clear and checked the ducting, which is all intact. Any ideas what to look at next? I’m not going to buy a new one but I don’t mind taking it out and stripping it down on a workbench if needs be.
South Eastern Auto Electrical Services of Tovil are generally pretty helpful over the phone. They have been fitting these as aftermarket equipment for many years. 01622 690010
Had that on a Scania it was a little silver box of tricks inside apparently would cost about 300 for the part and do , so we cannibalised another FUBAR’d unit and got it going 
Might be a thermostat fault.
Glow plug?
At the moment I’m thinking ecu. It is firing up properly, and throwing out a lot of heat but then it shuts down. I imagine that it thinks it is overheating?
What make is it ? On a webasto there’s a over heat sensor between the metal body and outer plastic casing easy to change , does is not have any self diagnose flashing led ?
I can’t see anywhere where three would be a flashing LED code, there’'s an on/off switch on the dashboard and a rotary rheostat in the rear wall, there’s not a control unit as such, advanced timings etc are done through the dashboard display and the night heater isn’t covered by the diagnostics. It is a Webasto and I’ll have a look at the overheat sensor when I get a mo.
Check where the vent where it ■■■■■ the air in, I’ve seen night heaters do exactly what you describe because the air inlet is partially blocked.
if their is a blue an white wire next to the heater put a led test lamp on it it will give you a flash code,not the fast ones count the slow ones then we can advise you,i use a screw driver with a led bulb in it,keith
Depends what type it is ,if its a wabco the triggering unit just sits on top.2 screws and three plugs to undo and pull it off.The new glow plug even comes with a “special” split box spanner so you can change it.10 minute job.
Erberspatcher you got to pull out the unit and take it apart.Inside is the fan ,heat exchanger and volute.Replace the glow plug and also the thermal probe.This tells the heater ECU that the fuel being pumped into the unit is burning.If it doesnt fire up because of a faulty glow plug or blocked air inlet it cuts out the pump.
When you try to start the heater fuel is pumped in but if the thermal probe does not get hot it cuts out after a few seconds.When you repair it get ready for a lot of smoke because it has to burn off the fuel that has been injected on previous start/fail cycles maybe even a few flames out the exhaust.
Had a few drivers rush in to tell me that the unit outside the garage is on fire due to all the smoke on its first start up after a repair
Harry Monk:
I can’t see anywhere where three would be a flashing LED code, there’'s an on/off switch on the dashboard and a rotary rheostat in the rear wall, there’s not a control unit as such, advanced timings etc are done through the dashboard display and the night heater isn’t covered by the diagnostics. It is a Webasto and I’ll have a look at the overheat sensor when I get a mo.
On webasto I have had your fault with a bad earth to battery neg but this was retro fitted, I wouldn’t know where to look on a Renault other than to make another earth lead up to try to experiment with .
I’ve found the fault code display which is built into the rheostat, eight long flashes followed by five short flashes, if anyone knows what that means.
It’s the 8 that are the code.
Fan motor interruption or fan motor short-circuit or incorrect fan motor speed.
Find the type of your night heather in the list. Maybe that will help.
I was getting overheating, power and other faults brought a recon heater only to find it was a fault with the pick up from the fuel tank. Might be worth a look that end!
first of all, if it fires up, put it on max temperature and see if it shuts down then. if it doesn’t, it’s just full of sud and should be cleaned out regularly - put on max for an hour or so, at least weekly.
Hot water bottle and a good sleeping bag ,what more could you ask for,summers on its way. 