I am not looking forward to suffering through another winter in my car. The heater is absolutely hopeless, the temperature takes forever to reach normal at the best of times but during the winter it is even worse. My journey to work is about 10 miles by dual carriageway and it is just beginning to get comfortable in the car by the time I arrive at work. When I first bought the car 8 years ago I took it to Mercedes because I could not believe it should be as bad as it is. They checked it out and told me "that is just the way they are, the best thing for you to do is to buy a hat and some gloves". Very witty indeed, but not exactly the thing you want to hear. Anyway I just wondered whether anyone else has experience of poor heating and if they have managed to improve matters somehow. The fact that it has some kind of an additional heating unit fitted that operates in low temperatures makes me think that it must be a design fault. This additional heater never seemed to work to me anyway so it is permanently switched off.
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ched999uk
Active Member
Does your water temp get to 80 deg C? If not first thing to try is the thermostat. Diesels do take more time to warm up than petrol but yours should be well warm after 10 miles. Either that or since new it has had a blocked heater matrix or associated pipework.
Does it ever get warm even if you travelled 100 miles?
Does it ever get warm even if you travelled 100 miles?
gkerr4
Active Member
hi - the obvious thing is to get your thermostat replaced - it should heat quicker than it does I would have thought. - it's not an expensive part although the labour will add up if you aren't doing it yourself.
second - have a google for auxiliary heaters - the common one is made by webasto - they can be run before you start the car - some on timers or even remote control - they use diesel fuel but heat the water in the cooling system to pre-heat the engine and cabin - my wifes VW touran has one which kicks in when the external temp is below 5deg C - you can really tell when it is on! (but mornings when it is 6 or 7 are still a pain!!)
second - have a google for auxiliary heaters - the common one is made by webasto - they can be run before you start the car - some on timers or even remote control - they use diesel fuel but heat the water in the cooling system to pre-heat the engine and cabin - my wifes VW touran has one which kicks in when the external temp is below 5deg C - you can really tell when it is on! (but mornings when it is 6 or 7 are still a pain!!)
Recently had the same problem. I had to travel over 30-40 miles to get some warm air inside. I swaped termostat and first of all I get heat inside after 5-7 min of trip to work (10min motorway driving) and best of all I could get over 30 mpg even on motorway trips. Recently done trip of 150 miles and I seen 42mpg - it will pay back in next 3 fill-ups.
I would change termostat regadless of other solutions. Specialy if you never had it done withing time you own vehicle.
I would change termostat regadless of other solutions. Specialy if you never had it done withing time you own vehicle.
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- 65 Plate E350 CDI Convertible, 2006 CLS 55 AMG, 1997 C230K, 1999 C43/55 AMG
If your car is fitted with one make sure the viscous fan coupling operates correctly, if it is U/S it could cause "over cooling".
Thanks for the replies. Even in the summer it does not go much above 80 degrees, I have never seen it go far above that point even after a good thrash. I guess a good starting point would be to replace the thermostat and see if that helps at all. I would be interested to know if anyone with a similar model has this problem. Apart from the dealers telling me that's the way they are I have also been told by a local independent Merc specialist that these engines are over cooled and that is why the auxiliary heaters were fitted.
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- Feb 8, 2007
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- Portsmouth, Hampshire.
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- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Does it have a viscous fan?
- Joined
- Feb 8, 2007
- Messages
- 20,433
- Location
- Portsmouth, Hampshire.
- Car
- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
The duo valves maybe stuck. They control the hot engine water the the interior heater matrix.
Try giving them a light tapwith a hammer.
They are located in front of the brake fluid resevoir.
Try giving them a light tapwith a hammer.
They are located in front of the brake fluid resevoir.
Tried giving the valves a bit of a tap, unfortunately it did not make any difference. I am going to change the thermostat and see if that helps. on my journey to work today I kept an eye on the temperature gauge to see what it actually reads. Even by the end of my trip to work (10 miles) it had not quite reached the mark in between the 40 and 80 on the gauge. Some warm air was coming out after about 3 or 4 miles but it was about 12 degrees outside today up here, this would not happen in really cold weather. Thanks for all of the replies, I am very grateful. I will report back when I get the thermostat changed.
From what you are saying my the temp guage not getting up to the correct temperature, it definately sounds like you have a thermostat issue.
Onve you have replaced the thermostat and if you still have problems check for the following :
Are the water pipes leaving the duo valves and entering the cabin hot ?
They should be hot if you have the temp up at max. If not, there is a possibility that either the duo valve or the controller is faulty.
Onve you have replaced the thermostat and if you still have problems check for the following :
Are the water pipes leaving the duo valves and entering the cabin hot ?
They should be hot if you have the temp up at max. If not, there is a possibility that either the duo valve or the controller is faulty.
Good news! Changed the thermostat today and took the car for a run, the temperature is now going almost up to the 80 degree mark, all of this week it had barely climbed above 40. Can't believe I have put up with this situation for all of this time. I should have tried this ages ago but to be honest the fact that the dealership and then someone else told me that this is how they were I did not think any more about it. Well, you live and learn.
