A heating problem...

[PhilP]

I have a 1990 230E W124 with a heating problem. If I use the temp wheels to turn the heating on (at its lowest setting) the temperature slowly rises to max, the wheel settings do not regulate the temp at all, their only use is to turn the heating on or off. There is no aircon, so the centre vents blow cold as intended, but the side vents get progressively hotter the longer you have the car running...
I recently visited three pointed parts and swapped out the heating matrix and duo valve whilst I was scavenging for a new interior, changing both of those parts for known working ones did not resolve the issue.
I was hoping someone has had, and solved, this issue before? Am I missing something obvious?

Thanks in advance for your help.

 

[kth286]

the heat is electronically controlled.

the sensor is normally in the overhead front roof light.

there is a fan in/behind the glovebox that feeds air via a pipe to the sensor.

check those items.

 

[PhilP]

Thanks, I will get on to that at the weekend!!

 

[Mike44]

My 124 is in at the moment having a new radiator and thermostat fitted. This is mainly due to the fact that the rad has gone but I too have had a problem with the heaters. The mechanic thinks this may solve both problems in one go. I'll let you know if it works!

 

[rumelk]

Heater Not Heating Up

I've got a heating issue related with my 93 w124 saloon. Its december now and its very cold outside and my car just does not want to heat up. The temprature gauge is fine (sits at about 80) however the heating just takes forever. The centre vents stay closed as its constantly blowing cold air, (theres no A/C).

Any suggestions as to what it be, and what part needs replacing. ideally a turbo charged heating system would be awesome, but if i could get some nice hot air circulation for the time being i will be very . Many Thanks

 

[PhilP]

the heat is electronically controlled.

the sensor is normally in the overhead front roof light.

there is a fan in/behind the glovebox that feeds air via a pipe to the sensor.

check those items.

Is this only if you have aircon/climate control? I have neither of these

 

[PhilP]

I have a 1990 230E W124 with a heating problem. If I use the temp wheels to turn the heating on (at its lowest setting) the temperature slowly rises to max, the wheel settings do not regulate the temp at all, their only use is to turn the heating on or off. There is no aircon, so the centre vents blow cold as intended, but the side vents get progressively hotter the longer you have the car running...
I recently visited three pointed parts and swapped out the heating matrix and duo valve whilst I was scavenging for a new interior, changing both of those parts for known working ones did not resolve the issue.
I was hoping someone has had, and solved, this issue before? Am I missing something obvious?

Thanks in advance for your help.

Turns out I didnt swap the matrix at all, just the heater switchgear, the matrix is a radiator that sits further forward. Perhaps I have an issue with the matrix then, would that explain the heating issue?

 

[kth286]

Is this only if you have aircon/climate control? I have neither of these

No - the 124 has accurate electronic control of it's cabin heating between a lower temp and an upper temp and your choice anywhere between those limits.

I do not remember the high and low limits numbers without looking it up.

The above is standard to all 124s without aircon or climate.

Aircon and climate add the cool air bit (when/if it is still working).

 

[rumelk]

I've got a heating issue related with my 93 w124 saloon. Its december now and its very cold outside and my car just does not want to heat up. The temprature gauge is fine (sits at about 80) however the heating just takes forever. The centre vents stay closed as its constantly blowing cold air, (theres no A/C).

Any suggestions as to what it be, and what part needs replacing. ideally a turbo charged heating system would be awesome, but if i could get some nice hot air circulation for the time being i will be very . Many Thanks