C320 Petrol, thermostat problem?

[DSM10000]

It was a brisk 3 degrees C as I set off this morning, normally the car is delivering warm air within a mile of driving off and is showing around 90 degrees C on the display by the time I get to the A36 about 6 miles from home.

The cabin did not seem to be as warm as expected from the position of the heater controls and on checking the dashboard read out it showed somewhere between 80 and 85 degrees after these 6 miles although it was at around 90 degrees C about a mile or so further on.

I had no issues with the heater output last year in very low temperatures so am unsure if I have the beginning of an early thermostat problem. The car has covered 110,000 miles and has not had the thermostat changed according to any paperwork I have.

Is it an easy change for a competent home mechanic or best left to my specialist? The problem is that he is usually very busy and at the moment due to personal commitments I do not have much spare time to drop off cars during the week.

Many thanks as ever.

 

[Stratman]

It's a common problem and an easy DIY job.

 

[DSM10000]

I am assuming that you need to drain some of the coolant to change it? Are there any special procedures for refilling and bleeding the system afterwards? Also, is there more than one thermostat type?
Thanks