You should have got a heating engineer not a plumber, who could have done the wiring as well.
The valve is normally cold when not in use, but...
Then how did you fit it to the system.?
The thermecouple needs replacing, have the boiler serviced by a local engineer, needs some TLC. Will not cost a great amount.
If you supply an email in your profile and you are an RGI, I will send you one, if your inbox will accept it.
Otherwise you can get one here...
You have an airlock in the hot water circuit.
Worst case secanario.... Gas
50mm from either side
min 760 directly above
unless manufacturers instructions specify different.
You can download manuals from Here.
Find the better one here: http://www.vipergas.co.uk/index.asp
No, it will not cause any harm.
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