Air Conditioning Passenger Only

Hi, I can't believe on the hottest day of the year the air con is now playing up. Only got full cold air on passenger side. Drivers air is warm and stale.
Went to see the local quick fit boys who checked the gas and compressor and said all was ok, didn't charge either.

When the heater control is turned to hot, temperature rises as usual. Occasionally when I open the car there is a loud clicking/ticking noise somewhere in the centre console which sounds like a stepper motor, it runs for about 10 seconds or so.
I can only assume the valve / motor which allows the conditioned air to the drivers side is playing up.
Has anyone ever replaced these?
Have had a look at RAVE but more confused now.
Ran allcoms but no faults on HEVAC.

Any help gratefully received.

Regards
Ian

Allcomms? so I'm guessing it's an L322? It would be a blend motor on a P38, L322 is stupidly complicated with old fashioned water valves etc so I don't know for sure, but it will be the temperature control mechanism failed.

Yep, the L322 uses valves to control water flow through the matrices (the Heater Matrix is in 2 halves - Passenger and Driver) Pre-conditioned air is then drawn over the matrices and into the cabin, if one water valve isn't closing properly, the air will be warmed as it passes over the matrix.

Saint.V8 said:

Yep, the L322 uses valves to control water flow through the matrices (the Heater Matrix is in 2 halves - Passenger and Driver) Pre-conditioned air is then drawn over the matrices and into the cabin, if one water valve isn't closing properly, the air will be warmed as it passes over the matrix.

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Areal bit of 60's tech