Discuss Viessmann combi starts when cold, mixer, tap is opened in the USA Plumbers Advice area at PlumbersForums.net

Messages
3
Recently had a Viessmann Vitodens combi boiler installed, quite often when the adjacent cold mixer tap is opened the boiler starts for a few seconds!
Can anyone tell me what is causing this?
And how to cure?
 
Needs a non return valve fitting on the cold to the boiler and a shock arrestor
 
Thank you Shaun for your reply and solution.
Might changing the tap from a mixer to two singles also cure the issue? {they are 45 years old!)

No as the issue is when you shut the tap a shock wave goes back through the pipes to the boiler and moves the flow switch
 

Reply to Viessmann combi starts when cold, mixer, tap is opened in the USA Plumbers Advice area at PlumbersForums.net

Newest Plumbing Threads

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock