I've replaced the matrix in the heater box but it hasn't sorted the lack of heat out so next stage is rebuilding the heater box and sealing it up properly. The foam on the flap was in a bad way when I put it back together but I could do with ordering it and having it here before I take it apart so it can be back on the road after a few hours.

Does anyone know the size of the foam piece? Anyone bought one and have a price/place?

I don't know the size but I tightened the wires on the heater box there's a sticky on here plus I changed the thermostat which made my heater hotter

superdougie said:

I don't know the size but I tightened the wires on the heater box there's a sticky on here plus I changed the thermostat which made my heater hotter

Click to expand...

Yeah I've been told to do that too! That's my next job!

superdougie said:

I don't know the size but I tightened the wires on the heater box there's a sticky on here plus I changed the thermostat which made my heater hotter

Click to expand...

The cables are right, it's an issue of not being air tight thats the problem. The air is either bypassing the matrix or the hot air is escaping/drawing in cooler air.

Hi, I did the same and had the same outcome. The old matrix had a foam seal top and bottom, the new matrix has neither and although it's a little bigger and a tight fit it's not tight enough, so it will leak air.

The foam seal your talking about is only about £8 from paddocks and is a must to be changed. I ended up removing the box and re-sealing every corner of the nix.
This was a good start but no way the end.

Another area to remember is that the air is blown in to a big void along the bulk head.
I ended up removing all my dash etc to re-seal the heater tray. This took three days but was worth it.

Now I'm going to sound stupid but I'm about to do it all again.
I'm going to take it all out and but it back, but with the tray/void lined with insulation. By insulating and reducing the size if the void, my plan is that the heat will get to the de-misters both faster and better.

I will be posting step by step pictures.

Hope you have better luck than I have had. I have flushed out the heater Matrix, changed three thermostats,tried a 88 degree one, removed the viscos fan, fitted and electric one, tried a rad muff and its still freezing when it gets really cold. I have no fitted a 300wat electric heater which does improve things a little.