Hi, my first post on this forum.
I have a RRS SVR 2015 and having issues with the heating. The car is only blowing cold air. The vehicle doesn’t lose coolant. It doesn’t over heat even on a long drive.
I have changed the pump on the side of the fuel burner heater and the solenoid underneath and still doesn’t make a difference.
Then you feel the pipes going to the heating matrix on the bulkhead, they are both cold. The pipes coming in/out of the fuel burning heater are also cold regardless of the car has been run for an hour.

Obviously we are desperate to get the issue fixed. Can anyone advise or point us in the right direction.

Any help is appreciated.

Sounds like the thermostat is not opening

Wouldn’t the system over heat or pressurise if the thermostat is not opening?

Red Arrow wrote:

Sounds like the thermostat is not opening

sounds like it might be the changeover valve on the FBH to me
same happened on my L322

I changed the valve with the FBH water pump. That side of the heating works remotely.

I’m going to change the thermostat tomorrow as I have noticed the coolant pipe underneath the expansion bottle with the bleed nipple is stone cold even after a long drive.

did you clear any fault codes after you changed it

Yes, all fault codes stored in the ecu were cleared. Fault codes attached.
The only code that keeps coming back is the windshield misting sensor.

So this evening I have had the thermostat changed and there appears to be no change. We are absolutely left baffled.

We have now had the thermostat, heating solenoid and pump on the FBH changed.

When I feel the pipes going into the heater matrix, they are cold. The pipes directly under the expansion bottle are also cold. The pipe south of the thermostat is also cold even after running the car for an hour.

We are now booking into a main dealership!