Sucking AIR

[PCDOCTOR]

Thanks for the reply

The present system has been in 10 years and i moved here 3 years ago so it not doing to bad until recently

At present i'm adjusting the Boiler temp to give me the 55 ~ 60 degrees i want at the furthest hot tap

My next step is to fit a 3 way valve and temp sensor to the tank

Can you see the present set up giving me any short term troubles

Oh forgot the hot water storage is at mains pressure

 

[Dan Robinson]

OK, now I am worried.

Turn it off and post back with a few pictures of the tank, and any controls/pipes that you can see between the tank and boiler.

 

[croydoncorgi]

I misread the diagram - the valve you asked about is presumably a 'fixed bypass' and needs to be slightly open.

I agree with Dan: if you have a mains-pressure hot water cylinder (ie. an 'unvented' type) you MUST have a spring-return zone valve on the hot Flow to it from the boiler. This is a major safety issue.

But it may actually be a heatstore that you have.....

Rather than stumbling about in the dark and getting potentially wrong/dangerous advice, I strongly suggest you Get Someone In who knows what they're doing.

 

[PCDOCTOR]

your getting me worried

Can anyone explain why my yearly BG inspection on the central heating is always a pass but not to current standards ??

Is someone giving me duff advice or is BG ripping me off and should see them in court on safety grounds

All i can say is arhhh just clicked just in case we crossed wires and it makes a difference is that there is a header tank in the loft that supplies the cold water to the Hot water storage tank

Does that make more sense

So should i leave that valve open - closed or partially open or does the above worrying issues still become a problem

 

[doitall]

One issue at a time, is the cylinder fed from the mains or a tank in the roof.

 

[PCDOCTOR]

Guys

Modified picture above to show Storage tank fed from tank in the attic

Hope this clears some grey areas

 

[GeckoGas-com]

Phewww!


Putting a 3-way valve in will do the job with some ancillary controls like room stat and cylinder stat....

Looks like you inherited a DIY system on day 1.... Unlucky begger.

 

[PCDOCTOR]

So

As the system is layed out at present it will work safely but needs an upgrade

Back to my question further up the tree does that valve need to be open or closed

 

[doitall]

So

As the system is layed out at present it will work safely but needs an upgrade

Back to my question further up the tree does that valve need to be open or closed

Watch my lips

Its a by-pass valve (4) and should be cracked open or changed for an auto by-pass valve

 

[PCDOCTOR]

WATCH MY LIPS

It is fully open as i was told earlier

BUT

As a few comments above make you stop and think when we are talking about hot water and gas you cannot be to careful and this area of work should be given respect

Hope you can show me some respect in the future as i do to you guys

 

[doitall]

It shouldn't be fully open so turn it off and open it one full turn, or as I said fit an auto valve which is what it should be anyway

 

[Softus]

Without a zone valve in the DHW primary I can't see any reason for valve #4 to be anything but closed.

 

[gas4you]

The NCS ticket is probably something to do with the boiler installation or position. Perhaps the flue is too cloe to an opening in the wall eg door or window, or even something simple like no terminal guard on the flue if it is less than 2m from the ground.

The NCS should tell you why it has been issued. The NCS only means that it would not be allowed to be fitted like that today, not that anything is unsafe.

 

[Dan Robinson]

Valve 4 is indeed a by-pass, when you put a control vavle on the system change this for a differential version. In the meantime you can have either closed or open a crack...

 

[chrishutt]

If you use a 3 port motorised valve and have some rads always on (not fitted with TRVs) then you won't need a by-pass at all. The only reason for a by-pass is to ensure minimum flow through the boiler at all times. If the heating and cylinder circuits provide that you don't need a by-pass.