Heating!

[Annu]

Hi Guys,

Sorry am new to this page and am not sure ive posted it in the right area.

I own a Mercedes CLK 2.2 2008 model. I have been experiencing issues with the Heating, its been blowing cold air. So i took it to my local garage and he replaced it with a new Thermostat and that still didn't do the trick, and he couldn't figure out whats wrong with it and asked me to take it to a Merc Specialist. The specialist said that there is blockage and needs a new radiator. So ive replaced the radiator, and its blowing warm air but doesn't get fully hot. The blockage has been cleaned many times and the specialist suspects that i have a lazy thermostat, do think that could be the case? Even tho the mechanic who replaced the thermostat disagrees.

Please could someone give good advice I feel like am going around in circles not knowing which part it is!?

Thanks

Annu

 

[ullwn]

FWIW....................

On some Mercedes vehicles there is a separate electrical pump that pumps the hot water to the heater.

I do not know if applicability{if you have a separate pump] to your model.

Joseph

 

[rf065]

the specialist suspects that i have a lazy thermostat, do think that could be the case? Even tho the mechanic who replaced the thermostat disagrees.

What make of thermostat did they fit, a cheap as chips budget special or a recognised OEM manufacturer part? Answer that and it may lead to you trying another thermostat?

 

[artyman]

I had a problem with heating in my C class a couple of years ago and had the heater regulator replaced, my indie also recommended replacing the Heater Motor at the same time, so that may be an area to investigate.

 

[Dodipops]

The blend flap motor could be faulty and not fully allowing the hot air in to the cab

 

[Annu]

FWIW....................

On some Mercedes vehicles there is a separate electrical pump that pumps the hot water to the heater.

I do not know if applicability{if you have a separate pump] to your model.

Joseph

 

[Annu]

I think on this model there’s one water pump. The pump has been replaced not so long ago. Today I checked to see if it was working well and I could see the water flowing the plastic tube into the engine.

 

[Annu]

What make of thermostat did they fit, a cheap as chips budget special or a recognised OEM manufacturer part? Answer that and it may lead to you trying another thermostat?

 

[Annu]

He said it was an OEM version but he also mentioned that previously we had changed the thermostat so his assuming that it may not be the thermostat? But I have read reviews that the OEM version doesn’t last long. I’ve only had this one in for two months. When he replaced it, it hardly made a difference it’s only when I had the radiator changed which made the difference. Despite the difference it’s still not blowing out hot air!

 

[Annu]

I had a problem with heating in my C class a couple of years ago and had the heater regulator replaced, my indie also recommended replacing the Heater Motor at the same time, so that may be an area to investigate.

 

[Annu]

What is a heater regulator? Sorry am not an engineer only lawyer by profession lol

 

[Annu]

The blend flap motor could be faulty and not fully allowing the hot air in to the cab

 

[Annu]

is that a heating matrix? Well what I have noticed is that when the heater is on the lowest level I.e 1 to 4 it’s blowing hot air but Switching it to the max it gives out Luke warm air.

 

[artyman]

What is a heater regulator? Sorry am not an engineer only lawyer by profession lol

Sorry no idea, I just relied on my Indie to sort the problem. Cars are far too complicated these days for my mechanical skills, the last car I had in bits was a 1970 Hillman Avenger!

 

[markjay]

When there's no warm air on the cabin, is the engine actually at normal operating temperature (i.e. above 80 degrees)?

If it is, then the thermostat isn't the issue here.

 

[markjay]

What is a heater regulator? Sorry am not an engineer only lawyer by profession lol

On older cars there's a cabin heater matrix under the dash. Operating the heater lever from the dash used to pull a rod that flipped a valve that allowed hot coolant to flow through the cabin heater Matrix. If the valve was stuck, it wasn't possible to heat the air that flows into the cabin.

 

[Flyinspanner]

Does your model have a valve which opens to send hot water to the heater matrix? It could be not operating properly, partial flow - so hot air at low fan setting, as enough water flow - but at higher settings not enough hot water flow to sustain the heat?

also, try to maybe flush the heater matrix with hosepipe/ and also reverse flush in case it’s a bit sludged up.

 

[Annu]

Does your model have a valve which opens to send hot water to the heater matrix? It could be not operating properly, partial flow - so hot air at low fan setting, as enough water flow - but at higher settings not enough hot water flow to sustain the heat?

also, try to maybe flush the heater matrix with hosepipe/ and also reverse flush in case it’s a bit sludged up.

Hi,

I don't think the heater matrix has been flushed, i did have a blockage due to the old coolant and as a result my mechanic has flushed the entire system but i am not sure if he has flushed the Matrix. This morning it took over 30 mins for my car to warm up as there has been frost. But i did notice that the Water Pump was heating up but when it came to the radiator pipe it wasnt hot. Is this normal?

 

[markjay]

Hi,

I don't think the heater matrix has been flushed, i did have a blockage due to the old coolant and as a result my mechanic has flushed the entire system but i am not sure if he has flushed the Matrix. This morning it took over 30 mins for my car to warm up as there has been frost. But i did notice that the Water Pump was heating up but when it came to the radiator pipe it wasnt hot. Is this normal?

Diesels do take their time heating-up, but 30 minutes does sound excessive.

And yes the radiator pipe will be cold until the thermostat opens and allows the hot coolant form the engine to circulate into the radiator.

With regards flushing the cooling system, setting all dash heater controls to maximum heat when flushing is a must, to ensure that the valve contorlling the heater matrix in the cabin is fully open and that the heater matrix get flushed together with the rest of the cooling system. Presumably your mechanic would have done that though.

 

[Annu]

Diesels do take their time heating-up, but 30 minutes does sound excessive.

And yes the radiator pipe will be cold until the thermostat opens and allows the hot coolant form the engine to circulate into the radiator.

With regards flushing the cooling system, setting all dash heater controls to maximum heat when flushing is a must, to ensure that the valve contorlling the heater matrix in the cabin is fully open and that the heater matrix get flushed together with the rest of the cooling system. Presumably your mechanic would have done that though.

Ive just spoken to him and his said that his done that all. He suspects that its the Thermostat or the Waterpump which was changed a few years ago. Am not sure what to do? As the person who fitted the Thermostat is of the understanding as it cant be the thermostat! Am not sure if i should go back to him and ask him to change the Thermostat and i still have the same issue.