Vaillant diverter valve - definite diagnosis ?

[Jethro]

Hi all,

after suffering for a few weeks with what I believe is a faulty diverter valve (symptoms, intermittent lack of hot water when heating is on, cured by removing the actuator and moving the pin in manually), we've just discovered we have one of these "bolier care plans". (As it turns out we meant to cancel it, but just recieved the renewal), So that's handy. As part of the scheme we get a "free" service, which is now booked for Monday.

We tried to tell the firm about the diverter valve, but were told the engineer has to make the diagnosis etc etc. Which is fair enough.

However, knowing Sods law, and having worked in Motor Mechanics more many years, I am well aware of the nature of intermittent faults to not happen when watched.

I'm afraid the engineer will come, everything will work, and he'll say "can't find anything wrong" and bugger off again, leading to the hilarious 10-time call out, before the thing finally breaks down on a bank holiday weekend.

Am I being overly worrysome ? Is there some test the engineer will to to be sure ? Or that I might suggest he does, if he can't find a fault ?

Thanks guys

[Spamlet]

You may find this link helpful:

they have been helpfully provided in previous threads on ch valves. In my experience it is usually the microswitches which get burned contacts and then the motor ends up driving to one position and not the other or sticks in the mid point (others claim the microswitches are very reliable). The mechanism is surprisingly clever but you may be able to decide what has gone wrong with yours from careful observation of the way the pipes heat up at various settings and listening to the motor as you make the various selections on the controller.

S

[Doctor Drivel]

Vaillant.