The heater on my 2003 Peugeot 307SE SW HDi110 has suddenly stopped working, it is only getting just lukewarm. The fan works and we have checked for water leaks and checked the water levels which are all OK. Could it be the thermostat? It has always worked fine up to now.

Rob Manton, October 2007

check there are no blockages in the flow from the engine rad. upper hose should be hotter than lower. significant difference would suggest a blockage. Often caused by not flushing the coolant often enough. I'm sur it will be the thermostat. It may be opening the flow to often, sort that with engine recommendations as it affects fuel economy and we all need to do our bit for the environment.
Wish peugoet thought of that when they designed this car!

Big D, February 2009

hi ye the thermostat would be a possible suspect also make sure there isnt any air in the system i.e a airlock

huskey, November 2008

No i i have had the same problem, make sure all ur fuses in glove box and underneath bonnet are all working. If they are, u may need a new heater fan motor or could even be the resistor

shazad, October 2008