Hot water from outside tap

[jayseeblue]

Hi, I have an odd problem...I moved an outside tap and I shut the mains stopcock off. When I opened the existing outside tap hot water came though but it wasn't under much pressure and didn't last for long.

There is no double check valve on the cold water feed to the
boiler, the manufacturer's instructions show that this should be
installed before the filling loop. Could this have anything to do with the problem and what is the purpose of this check valve?


Does the brass fitting at the end of the cold feed to the boiler (ie-
that goes into the boiler) incorporate a check valve?


As the original installer didn't put in a dcv how bad is this?


Also when the outside tap is being used you cannot fill the boiler and
also the shower doesn't work. The property has quite low pressure
water but is there any kind of equalising valve that should be
installed and where should it be installed?


When I arrived at the property they also said that the loft radiators
weren 't working. I bled the radiators for a few minutes (!!!!) and
everything ok. Could this be linked to the same problem?


Hope this makes sense and thankyou for any help


I am currently doing a gas course at MET-UK so am still at a learning
stage. I am looking for a full time placement (free!) from 30/11/09 in
Derbyshire, Nottinghamshire., Staffordshire or Leicestershire.


Jon

 

[doitall]

Well jacseeblue, having just wasted 5mins of my life reading your post, I think you should put the kit back in the car and finish the 10 week course first, before you get into real trouble.

 

[jayseeblue]

Why? Perhaps I wasn't clear that I was describing the symptoms of the originally positioned tap ie- before I put a spanner on it not after. So I think I've done the right thing in raising alarm bells if hot water comes out of it.

Finishing the course won't make any difference it's only safety not how to do the job!

Jon

 

[jayseeblue]

That might not be clear enough- problem occurred before I layed a spanner or did any work on the property.

 

[electronicsuk]

When you say 'hot water came out', how hot? It's not at all uncommon for poorly insulated CH/hot water pipework running near CW pipework to heat the cold water, which will flow warm from the cold tap until fresh, cold mains water works its way through the pipework.

 

[seco services]

how can you ask what is the purpose of a check valve and your doing a gas course ?

 

[seco services]

that shocked i posted twice

 

[jayseeblue]

I meant what is it's exact purpose in that particular location given that it is in the MI. I know what a check valve does (backflow etc) but it obviously mustn't have that much of a purpose if the original installer didn't install one.

It's a bit like you really, you know what an apostrophe does but you used your instead of you're in your post.

Jon

 

[jayseeblue]

Thanks for the reply, I think the water was around 30 degrees so I guess not that hot. What you say is a possibilty but I did get a gush of cold water come out first then the hot. It's just with the other problem of the rads needing bleeding I wondered if this was an indication of all not being well with the boiler internals.

Thanks

Jon

 

[Bahco]

Have I read it right that an outside tap is quite hot

Trace the feed pipe and see how it is supplying the outside tap.

 

[kevplumb]

run it for 2 mins is it still hot