Xantia 2ltr HDi Estate year 2000 heater blowing hot air constantly

[Lemaubec]

I have a year 2000 Xantia 2ltre HDi Estate.

A rare thing these days 220,000 KLM’s special Edition - Milesime - launched to celebrate year 2000

I’m new to this forum, but I am petrol head, trying his best to keep this lovely old estate running.

I’ve been restoring bikes and cars for over 50 years. The Citroen we have owned for 8 years now. ( I was going to post a picture, but can’t find the image loader button)

I had the usual problem with the blower transistors popping and replaced the unit with the heat sink using an OEM part. This has stopped it blowing full now when the ignition is switched on.

The aircon I don’t use, as the car stands about unused for months. I did have it regassed, but with it standing it finally stopped blowing cold again.

My problem is, despite putting to heater slide to cold - Blue - it constantly streams hot air through the system. I get no cooler air. This is not great when the outside temp is 38 degs!

If I set the ‘recirc’ button, the blower runs at a low constant speed, with warm air streaming. If I set the ‘fresh’ button. the blower seems to run very slow (putting the blower to auto does not change the speed) and again streams warm air.

Can anybody tell me where the warm cold/warm selection is made? In other words why is warm air streaming all the time?!

Where is it going wrong, where do I look now please?

Kind Regards.