Vaillant Turbomax 824e is my Diverter valve U/S

When my heating is on I can't get any hot water.

When my heating is off the radiators seem to have a mind of their own and heat up.

It is then pot luck as to whether I will get any hot water.

In the event of my needing to change the valve can anyone confirm how to drain the central heating on this model of boiler. Do you use the pressure release valve on the bottom left underside as it has a pipe running from it that goes through the wall to the outside?

Probably diverter - look thorugh previous postings - there's an easy way to test it.

Don't use the safety valve - it's not a drain off.

Just near the flow/retrun isolating valves you will see the drain-off valves.

Gasguru

Thanks for your prompt response. I have removed the motor head on the diverter valve and was able to move the pin back and forth with my long nose pliers.

Are there amy other tests that you can suggest to enable me to diagnose my fault. On the face of it it appears to be the valve as I am experiencing what appear to be typical symptoms. I don't want to spend a fortune as we will scrap the whole sytem in the spring if we get planning permission to convert our bungalow into a house!.

Thanks

Andy

You can manually move it to the required position.

Its probably stiff and not reliably moving on its own. They usually fail after a few years. The latest ones have been modified with an elongated ball.

Tony