Technical X250 heater

[Mouldy]

HI all,
I've got a 2010 X250 3.0l with a semi auto box. It has been converted by Autotrail in a motorhome.

The heater in the cab is really not that good, it does have aircon and I possibly need to get this re-gassed, but ignoring that for now, is there any obvious thing I should be looking at to get the heater to be more efficient? Or should I get the re-gas done first as a process of elimination?

Fan is fine at all speeds but the heat output seems intermittent, i.e. takes a very long time to produce any heat and then cools off for a bit before producing more heat. May take up to fifteen to eighteen miles of motorway before any heat is produced.

All pointers and help gratefully recieved!

 

[Anthony489]

Hi Mouldy

The re-gas will help with cooling, but will do nothing for you if it's heat you need !

The heat source is what's effectively a mini radiator fed with hot coolant from the engine via small bore hoses. It's possible one of these has got squashed, restricting the flow. Alternatively, you may have an air lock, so bleeding the system will help.

This all assumes that the main engine cooling is working as intended, i.e. the engine is getting up to the correct temperature and the thermostat isn't stuck open.

Finally, the hot air and the cool air from outside has to be blended by means of flaps within the ducting. These are either directly operated by the heater controls or via motors in more up to date sysyems. Any fault here might mean your precious hot air is being diverted away from the cab.

 

[Mouldy]

My bad, of course it's aircon and not climate control!!
Engine cooling seems to be ok, Although it did spike the other week so maybe there is some crap, (technical term!), floating around in the system? Maybe a drain and flushing of the coolant maybe the way forward.

Thanks for the reply.

 

[Anthony489]

Hi

Many modern vehicles, (probably the X250 included), have software between the temperature sensor and the needle on the display. So any temperature within an acceptable window (say 85 to 95 degrees C) gets displayed as "normal", i.e. bang in the middle of the gauge's range. Maybe they are set up this way so that people don't fret about normal minor fluctuations.


This does mean however that if the needle does stray above or below normal when driving after warmup, it's likely to point to something genuinely abnormal.


It's not impossible for a thermostat to stick partly open, so when the engine load is low it is over-cooled, but when you start to climb long hills and/or do a motorway run the flow is restricted and the temperature starts to climb too high.

 

[Mouldy]

I guess that could be an issue. Van hasn't been used much in the past twelve months due to Covid. I don't have a technical manual so where is the 'stat located?

 

[Anthony489]

Hi

The thermostat is inside a housing on the upper left hand side of the engine (as you look at it), just to the left of the inlet manifold. It connects to the large diameter upper hose of the radiator. See pictures attached.

 

[Mouldy]

Thanks fella. May end up throwing it a garage due to time, or lack there of! I'll report back with any findings.