Unvented System hammering noise

[David2749]

Hi all,
I've a unvented system and have experienced a few problems recently, namely when I turn the hot water tap on I hear a "water hammering" noise coming from where the tank is, and droplets of water going through the tundish . I've checked the expansion tank pressure and that seems fine 3 bar.
I've now managed to get a guy to come in to check the un vented tank, he states he is qualified to service un vented tanks.
I think I know what the problem is, the "high rate inlet control set" valve.
The question I'd like you guys to give me assurance of, when I asked the guy if the tank needs draining to clean out the mesh filter within the valve, as the valve is sited half way down the tank? The guy said no when the mesh is cleaned out no water will appear!!
I don't want to sound as if I know far too much, but I I'd like to know something before I let this guy into my house, as he is charging me £250 to service my tank.

Cheers

 

[muggles]

£250 is rather a lot, I'd be charging £65+vat for that. Don't go trying to tell him how to do his job though, that's just going to get his back up.

 

[David2749]

I thought that was a high price, but getting someone was not easy.
I'm not going to tell him how to do it, but from past experiences I dont want my house flooded.
Just by looking at the location of the valve it seems that the tank would need draining to at least the level of the valve.

 

[oldbuffer]

Or the pipework freezing.

 

[JimCrow]

Hi all,
I've a unvented system and have experienced a few problems recently, namely when I turn the hot water tap on I hear a "water hammering" noise coming from where the tank is, and droplets of water going through the tundish . I've checked the expansion tank pressure and that seems fine 3 bar.
I've now managed to get a guy to come in to check the un vented tank, he states he is qualified to service un vented tanks.
I think I know what the problem is, the "high rate inlet control set" valve.
The question I'd like you guys to give me assurance of, when I asked the guy if the tank needs draining to clean out the mesh filter within the valve, as the valve is sited half way down the tank? The guy said no when the mesh is cleaned out no water will appear!!
I don't want to sound as if I know far too much, but I I'd like to know something before I let this guy into my house, as he is charging me £250 to service my tank.

Cheers

Did you isolate the cold water and open a hot tap before you checked the pressure?.

 

[David2749]

Hi
I had a guy come around this morning, to resolve my issue on my un vented tank.
I wanted to observe what he was doing, out of interest. After taking the cover off the valve he then started to undue a nut, I asked him if the tank needed draining. At this point I asked to see his certificate G3, guess what he had left it at home. I wasnt happy so asked him to leave it. He was not too happy.
From previous experience I had had my house flooded by someone claiming

 

[David2749]

Just an up date I've now got a definately G3 registered plumber from check a trader web sit to visit my house who will charge me £ 80 to service my tank.

 

[David2749]

Hi all,
I dont want to sound as if I know what I'm doing, just had a plumber around to service my unvented tank.
All he did was check the pressure in the expansion tank , turned the red knobs on 2 valves and charged me £80.
When I asked him about checking the mesh in the valve, he told me that never needs checking.
I know the pressure was ok, as I checked this yesterday.
I just feel let down by so call experts. Who do you trust??

 

[David2749]

Hi
I did open a thread regarding my problem but cant locate this now?
I've had a problem when I turn the hot water on I get a noise from the tank area, from previous threads it was suggested it might be the pressure release valve, and the mesh might need clearing. I had already checked the expansion tank pressure as be 3 bar, as a slight drop was coming through the tun dish.
I had a guy, G3 registered , come around to apparently service the unvented tank charged me £80, all he did was check the tank pressure and turned the 2 red knobs on the valves. When I ask him about the cleaning of the mesh, he stated that it never needs clearing.
After he left, after an hour or so, when I turned the hot water on the noise is still there.
I've tried to call the plumber back and all I get is leave a message....
I fell I could have done everything he did and saved £80.