Got my air-con working OK today.I fitted a shut off valve in the top hose to the heater-box.This means that all you get is refridgerated air from the vents.Still got to try it long term but it does seem to have done the job.


How did you come up with that mod? Any known drawbacks (eg. gas runs out quicker)? Pics?

Sorry for all the questions, but this is news!


All I,ve done is to stop cooling-system water entering the heater box.In winter I can turn the valve and the heater works as normal.I think that the problem with the air-con is that as the engine warms up the heat overpowers the cooled air.Starting up from cold the air is chilled well but as the engine warms up the air from the vents gets warmer even with air-con on.So no hot water in the heater-box means the air-con keeps working.

Hmmm, don’t know about the coolant routing in an AC car, but in the non-AC, collant needs to pass through the heater until the thermostat opens, otherwise there would be no flow and the engine would boil its water locally!
That is the “small” circuit.
Maybe the AC cars have a different arrangement, but check it out just in case, you don’t want to be bocking a vital path.

Tried out my air-con on the way back to Yorkshire from the Brands EVO track day last monday(6th)and it works well.All engine temps were the same (79-83)and I had the recirculation so it picked up air from the interior.For the first time ever on a warm day the interior was cool.OAT must have been 25 or so and when I opened the valve to test things the interior very quickly became uncomfortable.Best thing of all is that the mod only cost a fiver(1 valve,2 40mm lengths of 15mm copper pipe and 2 hose-clips).

Getting even more interested. Any chance of a pic and/or diag?



I am also VERY interested!!!


Pictures please !

Pics will follow ASAP but basically I cut about 50cm out of the top hose into the heater box so that I could place an inline valve that I bought from a plumbers stockist.This had inlet and outlet for 15mm pipe so I placed about 20mm of copper pipe into each end.The hose has 16mm ID so I flared the end of both pipes so they couldnt come off.The seal is 100% watertight and when the water flow to the heater box is shut off the result is excellent.As standard either the hot doesnt shut off completely or the heater box is too small to separate hot and cold air.

Thanks DUCATIMAN, I look forward to the pics.

Did you drain the system to carry out the work, or just crimp the hose at either end?


I just crimped the hose.Interestingly,this weeks Autocar has the same criticism of the 111R air-con-works well on start up and then gives up.If you look at the arrangement to shut of the hot air it really does look very basic-I cant even see a way to adjust it.