Disappointed with Eberspacher Heater

[richard]

My Hylo Exclusive fitted with an Eberspacher heater purchased May 06 has been lightly used until I took it to France last week: two one week long holidays plus a few long weekends. Yet last week I found that the cabin heating was most temperamental. Sometimes the heating didn't seem to light at all: turn off and restart. On a number of occasions the hot water was heated but the fan cabin heating failed to start: especially when started on a low fan setting. Sometimes I found that by starting when switched to hot water only and then switching to hot water and fan heating, with the fan setting midway between max and min, I would get the fan to operate. In any event there seems to be quite a delay between switching on and anything happening. None of which is very helpful when you wake up at 5.00AM on a cold spring morning and all you want to do is warm up quickly while you doze back to sleep!

NB: The header tank for the heating system was always kept above the Min level, althought admittedly for the first couple of days it was only just above that level until I filled it up to Max.

Yet: The Romahome instruction manual refers to the Eberspacher Manual for how to operate the heater. In this it states that when you want to use the fan heater it should be set on its lowest setting when switching on. But, from the description it seems to imply that the heater is using the vehicle's engine cooling system

So what I am after is:
Advice about what I may have been doing wrong, about fan settings when starting and closing down (I have heard that with other heaters it is best to run at maximum fan for a few minutes before closing down in order to get rid of any carbon build up), any other helpful advice and suggestions to Romahome as to how they could make their manual more helpful in this respect.

Ant, I hope you can help!
Many thanks,
Richard.

[ant]

Hi Richard.
Firstly stop reading the book, it will only confuse you!
Secondly , you talk of the fan speed setting, the fan speed is automatically controlled by the heaters ecu. I think you are confusing the thermostat control as a fan speed setting control.
There are three things that are important to get right when using the heater.
1, Fuel, the heater is fed from the return pipe into the tank, this means you must have more than a third of a tank of fuel for the return pipe to reach the diesel in the tank.
2, Battery voltage, the heater is very fussy about having enough voltage to complete its lighting up cycle, if the voltage in your battery is a bit low start the engine and run it while lighting the heater, once its going you can turn the engine off. DO NOT try and start the heater with low battery voltage more than three times as it will lock out and require a £280 +vat part to un lock it.
3 Always start the heater with the thermostat control wheel on full ( the confused fan speed wheel). By start it on full the heater will not make any judgements about is it or isn't it cold enough to start the heater.
Once the heater is going and hot air is being blown out at full speed you can turn the thermostat down and as the temp' approaches the chosen temp setting the fan will automatically begin to slow down, eventually just running very slowly.
The heater will only run for an hour before resetting, if this happens to be at night it will relight once the temp has dropped well below the thermstat setting.
If you shut the heater off yourself it will continue to run while it shuts down and purges the system of unburnt fuel ( smell of diesel fumes sometimes).
Lastly, nothing happens instantly with the eberspacher, each process takes about 60 seconds to complete before you notice any change.
Hope this helps
Ant

[richard]

Ant, Many thanks for all that. Just some clarification on one point: Is it best practice to turn the thermostatic control up to max immediately before turning off so as to get rid of any carbon build up?
Perhaps when you next speak to Romahome you can suggest they expand on their instructions. I cant remember reading anywhere that the main deisel tank should be at least one third full!
Richard.

[ant]

Richard.
The heater automatically deals with any carbon build up in its shutting down cycle which uses as much electrical power as its lighting up cycle, so there is no need to change the thermostat setting. The response time of the heater changing the thermostat would probably not be registered before the heater shut down anyway.
I only discovered the tank level problem by mistake when my own heater started to run fast with cold air, on filling the tank as a last resort after a lot of testing and searching the problem was cured and never repeated itself while the tank was over a third full.
Ant
Ant