Xantia heater issues...

[CitroJim]

I ordered a resistor module from ebay and it was rubbish and didnt work at all.

Indeed I examined one of these a while back and was shocked to discover it had totally the wrong power transistors fitted NPN ones instead of PNP...

In fairness, the part number on the transistors were only one digit different but that made all the difference...

Faulty (genuine) ones are very amenable to repair and I've somewhere published a 'how to' somewhere on this forum...

[Mark Graham]

little bit of an update, I think there was a small air lock in the heater matrix. I didnt manage to get coolant to flow out the bleed valve but i think i got most of the air out and i now have warm air!

The flap seems to be working as i can change it from cold to warm air

Even though the coolant was just changed it looks very rusty to me which makes me think that it was mostly water before it was changed, I think i am going to drain the coolant again and flush out matrix, engine and radiator in turn.

[CitroJim]

Mark, excellent Progress!

Yes, do flush the cooling system and refill with a good antifreeze mix. The engine will thank you as they thrive on a well maintained cooling system and quickly object if not so. Do also check your cooling fans work too...

[white exec]

Result! Good news.
Air-locks in the heater matrix (and worse, the cylinder head) are not unknown, and it helps to use a temporary "header bottle" to force air out of the system after refilling it.

Any 1L bottle will do, bottom cut off, and a short length of old hose, with a snug fit into the car's header tank, so it blocks off the overflow hole. Keep the bottle at least half-full of coolant as the engine gets up to full working temperature, indicated by the fans cutting in at least twice. The additional head of coolant encourages air out of the system, and out of the bleed screws. It also allows you to easily see when air has stopped coming out of the system. Leave in place while the engine cools.

[admiral51]

Good progress Mark

On a side note if the resistor replacement does not work i have a blower motor from a MK2 that is yours for postage costs

[Mark Graham]

Result! Good news.
Air-locks in the heater matrix (and worse, the cylinder head) are not unknown, and it helps to use a temporary "header bottle" to force air out of the system after refilling it.



Any 1L bottle will do, bottom cut off, and a short length of old hose, with a snug fit into the car's header tank, so it blocks off the overflow hole. Keep the bottle at least half-full of coolant as the engine gets up to full working temperature, indicated by the fans cutting in at least twice. The additional head of coolant encourages air out of the system, and out of the bleed screws. It also allows you to easily see when air has stopped coming out of the system. Leave in place while the engine cools.

thank you very much! Worked a treat, no airlocks now

[Mark Graham]

Good progress Mark

On a side note if the resistor replacement does not work i have a blower motor from a MK2 that is yours for postage costs

Thank you very much for the offer! I will let you know when the replacement i ordered arrives