No heater in van :(

[NozSpark]

The title says it all really, but I will explain.

On idle (with engine warm) I get very little heat, if any, from my heater.

While driving along I get heat, but when I slow down for a junction or roundabout it goes cold again.

Temp gauge works and coolant expansion vessel has correct level of coolant..

It's starting to get blinking cold in my van now so any ieas will be gratefully received.

 

[steptoe]

1 airlock,

2 is there a blockage somewhere in the heater pipes?

3 is the fan actually working?

4 is the heater radiator blocked up? (leaves at this time of year is very likely.)

3 or 4 most likely IME

 

[Sidewinder]

Low coolant level in rad would be my 1st check.

I realise you have said the exp bottle is full, just had exact same problem with wifies car.

Leaking water pump & rad!

Loosing coolant enough to starve the heater matrix but not emptying the expansion bottle.

Check cold - obviously!

However, if you are careful then you can check hot and if you have little or no pressure, only around 1 bar (14-15psi) normally then you'll have a cooling system leak.

Not up you're way until 6th Dec you could freeze to death by then, otherwise I'd offer to bring my cooling system pressure tester up!

 

[Bez]

Check for leak in heater matrix, or as steps says, blockage, unusual to be blocked with leaves though as they're normally tucked away behind dash, low down in a central position. (lovely job to get at em')

 

[NozSpark]

Cheers guys..

The fan works perfectly!

NO water EVER in footwell (except from wet boots!)

I do get heat, but only at revs... not at idle or low revs!

So it sounds like an airlock or possibly leaves in the inlet.. TBH the bonnet gets lifted far too infrequently!

 

[PC Electrics]

Water pump impeller blades corroded away, can only pump water when speed is up. Diesels produce very little excess heat at idle so it doesn't cause an overheat yet (would if it were a petrol). How old is it and when was the coolant last refreshed? The anti corrosion pack on standard antifreeze is only good for 2 to 3 years.

 

[NozSpark]

Water pump impeller blades corroded away, can only pump water when speed is up. Diesels produce very little excess heat at idle so it doesn't cause an overheat yet (would if it were a petrol). How old is it and when was the coolant last refreshed? The anti corrosion pack on standard antifreeze is only good for 2 to 3 years.

Full of hope you are

TBH it was a thought:_|, but I'll try the other options first if you don't mind

 

[sellers]

As PC says the water pump blades could be the issue.

Unless the fan isn't working? Now not sure if this is notifiable? Must depend where you park it.

 

[steptoe]

heating systems,

deffo notifiable.

 

[revjames]

Sounds very much like poor water circulation. Air locks tend to casuse overheating and root cause usually head gasket. Might be worth checking thermostat first if it stays open then the water is going though rad and matrix all the time and overcooling. Just a thought.

 

[Cirrus]

If the van is a Ford then pretty standard!

 

[batty]

If the van is a Ford then pretty standard!

Thats racist my 13 year old Transit has a brilliant heater now i've said that it will probably break.

 

[NozSpark]

Not a Ford, it's French muck (a Renault Kangoo 655d)

 

[PC Electrics]

Could also be corrosion settled in the heater matrix causing a partial blockage that the pump cannot overcome at low speed.

You didn't answer my questions. Your answer might help to assess the likelyhood of corrosion being the cause.

What colour is the coolant in the expansion tank? Is it brownish with a skum or bright pink or green?

Most garages can test the effectiveness of the coolant anti corrosion package to see if the coolant has reached the end of its life.

If we suspect corrosion, you can try flushing out the system using a hose pipe. Flush the major component areas separately if you can get the hoses off.

Refill with tap water initially to see if the problem is cured or improved. If so, use a chemical cleaner to flush then fill with 30% long life antifreeze and 70% de-ionised water (not tap water).

 

[Theorysparky]

what was the last thing you did before it stopped working ???

change the coolant ????

or put a picture up ??????

 

[NozSpark]

OK,ok PC

Van is a 2000 (Y reg) 1.9d (not turbo), it's done 130k miles, last oil & filters change was a couple of months ago.... (probably stupidly) the coolant has not been changed since before I had it and IIRC is a slightly brownish colour.

There you go

 

[NozSpark]

what was the last thing you did before it stopped working ???change the coolant ????

or put a picture up ??????

Probably nailed some floor boards down, they squeaked a hell of a lot, but not now

---------- AUTO MERGE Post added at 22:36 ---------- Previous post was at 22:35 ----------

If you have heated seats ( I have them in VW T5) then turn on till your heater matrix problem is fixed

I'm lucky to have seats, never mind heated ones

 

[PC Electrics]

OK,ok PCVan is a 2000 (Y reg) 1.9d (not turbo), it's done 130k miles, last oil & filters change was a couple of months ago.... (probably stupidly) the coolant has not been changed since before I had it and IIRC is a slightly brownish colour.

There you go

Standard antifreeze is green, long life is pink.

Brown colour caused by corrosion.

Try flushing out first as a low cost fix.

Get that garden hose working for you.

Remove the stat to help too (if it's caked brown, get a new one).

 

[Sidewinder]

PC I have long life antifreeze that's blue!

2nd the flush.

IF the rad is full, never mind the expansion bottle, especially if the header is full of brown muck, the bleed valve in the pressure cap could be blocked and not drawing in the coolant from the exp bottle.

 

[NozSpark]

I think in order of cost I'll....

Make sure inlet is clear of leaves etc

Try and clear any possible air locks

Flush the cooling system

Change the thermostat

Replace the pump (and cam belt and pulleys while they're there)

Oh and not forgetting to put some fresh anti freeze in once I've got it working!