heater only blows luke warm

hi. i have a 2001 td5 auto 117000 on the clock . a while ago when it turned a bit chilly put the heater on hadnt used it all summer would only blow luke warm.temp gauge was up to half way where it normally sits i did a post only replies were are you loosing water?. not lost any water my mate who is a mechanic said lets flush it out with a hose pipe nothing to loose. we gave it a good flush out. i was a bit scepticle as there didnt seem to be any crud that was flushed out. filled it up with new anti freeze and bingo heater now blows out red hot . ps if any one tries this dont try and take the water pipes off the ones that go into the bulkhead to the heater. very difficult to get at the clips that hold them on .we took the one off that goes to the fuel heater and the one that comes out of the middle of the bulkhead attach the hose to this pipe it wouldnt blow through putting it on the fuel heater pipe. hope this might help someone with same problem.

The heater on the D2's is a mixer type, the water flows all the time, so it sounds like you have had an airlock in the matrix.

Peter

ok thanks for that allthough it seems strange the heater has been working fine for the six years i have had the car and i havnt lost any water.

I would suggest that your thermostat needs replacing. Don't buy cheap for this item - it's a relatively sophisticated device and needs to work as per mfr spec.

Dave