Help! I have no heat.

[goheel]

The vents on my 94 540 blow cold hair even though I had it on heat setting. Does anybody know what's going on? I'm also hearing the "clicking" sound where the temperature controller is. It sucks to have no heat in the winter.:(

[acidfire52]

Check this out...

Heater valve Check (http://www.bmwe34.net/e34main/Maintenance/Electrical/HeaterValve.htm)

Or, check your coolant levels.. If you are low, you will have no heat.

[goheel]

I did refill the coolant. I thought the heater valve problem applies when you get heat at maximum setting only. I get NO heat at all.

[acidfire52]

well, i don't know what to tell ya next...

Ther are some pretty smart guys here, sure one of them can help.

[opivy15]

Not sure if 94's have electroic actuators or not....If your buttons are push buttons then it does. If you physically have to turn a knob then there is a possibility it is a mechanical linkage.

If you have electroic actuators the motor could have broke or the temp door plate could be broken. Basically the temp door is stuck on cold air only. If this is the case you need a new acutator. A good way to tell is if you can drive the car inside somewhere so it is sucking warm air from the outside...then if warm air comes through the vent then you know its the temp door.

[goheel]

My car has the temp control knobs where you have to turn them, so I guess the electronic actuators possibility is not it.

[colo525i]

Even though there are knobs, they control electric valves that modulate the heat. It sounds as if they are stuck shut or not getting coolant. My car would whine about low coolant when i had a leaky hose long before i lost the heat.

Easy way to check them is to start the car, run it to temperature, set the heat to full blast and feel the valves. If they are hot, they are getting coolant. Then check the hoses feeding into the cabin, if those are also warm, the heater cores are getting coolant.

If the control valves are cold, the warm coolant from the engine is not getting to them, you may have an air bubble trapped in the system. If the valves seem to be getting heat but not the hoses to the cabin, try the trick mentioned in the link acidfire52 posted about smacking the heater valves. Mine would work occasionally on full blast, then started to not work at all. Rapping on them with a screwdriver (on the metal part) has cleared that up.