Hot water problems on unvented cylinder

[newcomers]

I had my whole central heating system refitted 7 years ago, and had a vaillant fitted with an ariston unvented cylinder.

All of a sudden the shower went cold when set to max temperature and the only way to get it hot was too basically shut the cold supply to the bathroom (gate valve) only leaving it partially open. This gave us a hot shower but flow to the cold taps was reduced.

Its been bothering me so tonight I opened up both gate valves fully and using a flow cup measured the flow. Both hot and cold were producing roughly 12 ltrs/min. The incoming cold temp is 11d and the hot was only 45d. I turned up the cylinder stat and now the hot is 62d. However I still have the same problem when the hot water gate valve is fully open.

I have noticed that the kitchen seems to be fine and works perfectly. One thing I will add is that the cold water draw off doesnt come out of the combination valve so it isnt balanced, but it has always been like this. The water main comes in under the stairs, and tees off to the loft and to the kicthen (cold tap, dishwasher, washer feed)

Once in the loft, it tees off again, one going to the cylinder and the other back down to the bathroom. I cant think what may have caused this as all was well for over 6 years.

Could it be a faulty cartridge in the combination valve? I took it out to have a look but all seemed ok.

Thanks

 

[Elkato531]

Unvented cylinders should only be maintained by suitably qualified persons. I'd advise getting someone in.

 

[newcomers]

I am qualified

 

[Elkato531]

Your original post read as though it was from an enthusiastic diyer. Had you said you were qualified, my reply would have been exactly the same due to the likelyhood of this post being read by unqualified people wanting to tamper with their own systems

 

[newcomers]

So do you not offer advise on any threads just in case someone unqualified reads them and attempts their own repairs? Im confused as I thought this is where people in the trade helped each other out

 

[Dan Robinson]

This is a DIY forum.

The clue is in the name


The Combustion Chamber is where to get professional advice on controlled appliances.