Bunk heater in a 2007 Volvo

what's the manufacture of the bunk heater?

 

Do you hear clicking outside? There should be a fuel pump about the size of 2 rolls of quarters that should click. If it clicks the pump is getting fuel. Check fuse. Check that fue isnt gelled

 

On the SET ON/OFF + - panel press on
the panel above should come on
press + or - until panel says heat
after this press the fan switch and the panel will have 1/2/3/4 on it
you should hear the fan come on
it will take a few min for the bunk heater to fully heat up

 

Shut it of. Lift up your bed locate the heater, there should be green bulb on the wires. Start your heater and once it stops by itself that green indicator will flash. Count the number of flasher, number of flashes is a fault code. Or another thing heater should have iet hose to cool heater follow that inlet hose make sure nothing is caught at the start of inlet hose

 

Bunk heaters are fickle things. Look under the truck, directly under the bunk heater. There'll be an inlet, and outlet, and a fuel line usually in between the two. Make sure that's connected. Normally on the driver's side by the fuel tank is where you'll find the fuel pump for the bunk heater. Not sure if this is applicable to all brands, but I know ours are supposed to be at a 45 degree angle. Barring that, before you go taking it apart, check your batteries. If your batteries are marginal or bad, your bunk heater won't operate.
The next step after that would be to check the ECM for fault codes, but you'd have to either have the software or go to someone who does for that.
We have the Espar heaters... they're bad for the fan motors going out.

 

First make sure it's set right. You have Off/Auto/On commands on the heater. If you have it on Auto with a low temp setting it will act that way.

Make sure it isn't on Auto and like 45 degrees or something ridiculous.

I doubt this is anything but on the bottom of that panel you'll see a little door. Those are your bunk fuses under it. You might try pulling the heater fuse and possibly reset the control module.

Another possibility other than what others said it has a thermistor that shuts the fuel down in case of igniter failure. The thermistor (has different names) could be bad. Any of them problems you are headed to a shop so there is no sense trying to figure it out. Just call your shop, breakdown or dispatcher depending on your company departments and procedures.

I'm pretty sure you have a Webasto heater which are common factory installed Volvo heaters.

 

Here's some more directions for that panel. Some have a plus/minus knob, some have the buttons but same directions.

I'd give you the link but I'm too embarrassed to give out my CREngland How to Drive a Volvo Truck Manual pdf!