Cold heater (HVAC)

Hi all,

I have a 2000 p38 4.6 vogue with an LPG conversion and the heater doesn't seem to be very effective, even on a 2 hour drive, I had to keep my coat on.

The test book symbol is not showing on the HVAC unit and when I adjust the temperature from cold to hot, it goes from cold to luke warm, never hot (Although the HVAC unit shows hot).

I have changed the thermostat as I noticed the engine temperature guage dropping when I was going down hill, with the new thermostat the engine temp is stable.

When I changed the thermostat, I flushed the heater matrix and I have checked all the pipes get hot when the engine is running (hopefully no air locks).

My LPG is system is plumbed in series with my heater matrix (coolant flows through the LPG vapourisor then into the heater matrix).

Is it likely that the LPG system is cooling the coolant so much that the heater matrix is not getting hot enough or restrictung the flow to the heater matrix?

I am considering using some T pieces to put the LPG vapourisor in parallel with the heater, has anyone got a set-up where they are in parallel?

Any advice on how to fix?
Andy

pretty sure mine is will check in the morning and let you know

The LPG on my Disco II is in parallel with the heater. I suspect that it's better in series really though as in parallel there is the possibility of the flow going through the LPG and not as much through the heater.

Regards

Ben

Could my vapouriser be restricting the flow to the heater matrix?

Is your vapouriser getting hot on both the inlet and outlet pipe or is it freezing ? you will know if its freezing as it will have frost on it ?
bleed the system throughly and try it again it should not reduce the water trmp too much

ovalandrover said:

Is your vapouriser getting hot on both the inlet and outlet pipe or is it freezing ? you will know if its freezing as it will have frost on it ?
bleed the system throughly and try it again it should not reduce the water trmp too much

Click to expand...

The LPG is working fine, no problems, it is the lack of proper warm air out of the heater (Even with the heater on HI) that I am concerned with.

The heater pipes do get hot, but the one from the Vapouriser to the heater matrix is cool enough to hold in you hand, but the other pipes are to hot to hold.

I gues I probably need to get the Tpieces and see what happend when I change the system from series to parallel