Heater only blows cold air

Sun Oct 04, 2009 12:25 pm

I got a problem with my heater on my e30 it only seems to blow cold air even when set to hot. The temp on the car seems fine its not overheating or anything. anyone have any ideas what the problem may be?

Sun Oct 04, 2009 12:34 pm

gurps_singh1 wrote:I got a problem with my heater on my e30 it only seems to blow cold air even when set to hot. The temp on the car seems fine its not overheating or anything. anyone have any ideas what the problem may be?

Have you checked for airlocks in the cooling system?
If so, when was the last time you replaced the thermostat?

Sun Oct 04, 2009 1:50 pm

Anyone had the heater hoses off under the bonnet at any time?
Check they are on the correct way around (one from the back of the head to the lower stub on the bulkhead.)

Sun Oct 04, 2009 6:26 pm

mine has just started doing the same i got a feeling its the valve behind the dash as its not making a noise when you turn the temp control from cold to hot

Sun Oct 04, 2009 6:47 pm

have a look in the wiki ..there are a few articles

Sun Oct 04, 2009 6:59 pm

tomti wrote:mine has just started doing the same i got a feeling its the valve behind the dash as its not making a noise when you turn the temp control from cold to hot

?? What noise do you expect it to make??

Sun Oct 04, 2009 7:02 pm

when i got near it shouldn't it make a flappy noise like the slider controls do when i turn from hot to cold?

Sun Oct 04, 2009 7:02 pm

My heater heats the footwells fine and also a little on the screen (enough to de-mist it) but only pushes cold air out straight ahead through the passenger and driver vents. Is that a valve problem?

Sun Oct 04, 2009 7:26 pm

Hellbound wrote:My heater heats the footwells fine and also a little on the screen (enough to de-mist it) but only pushes cold air out straight ahead through the passenger and driver vents. Is that a valve problem?

Passenger and driver vents should still be blowing cold air when heater knob is turned so that the screen and footwell vents are blowing warm air.
When the temperature knob is turned to its higher reaches, the face vents should start blowing hot as well.
If this don't happen, there's a problem with the bowden cables.

Sun Oct 04, 2009 7:27 pm

tomti wrote:when i got near it shouldn't it make a flappy noise like the slider controls do when i turn from hot to cold?

Only if the pipes are on the wrong way around!

Sun Oct 04, 2009 7:29 pm

ok maybe it shouldn't make a noise then do you think this is why my heater is cold? any idea how much they are from bmw?

Sun Oct 04, 2009 9:24 pm

Brianmoooore wrote:Only if the pipes are on the wrong way around!

Tue Jul 16, 2013 10:34 pm

Brianmoooore wrote:Check they are on the correct way around (one from the back of the head to the lower stub on the bulkhead.)

Thanks, I took this advice, after my engine change, the temp. guage wouldn't move out of the blue, the heater was stone cold, there was a dripping sound, coming from the heater valve, luckily it was bone dry! Swapped the hoses around, all sorted now!