Central Heating - No Hot Water

[wysokoa]

I have a Potterton Boiler and Santon Cylinder (PP150B Indirect)

I have Central Heating but no Hot Water.

I am confused because I have a silver Honeywell (400 3916 001) box and the pipes on both sides of this are very HOT.

I have a black seimens box (ZA-V222C) seimens is also the boiler controller) and the pipes on boths sides of this are very HOT.

When I start to lift the cover on the Siemens box there is a bang and a switch moves from H to M then slowly back to H. Whats all that about?

Would really appreciated some help.

Thanks and Merry Christmas.

Matt

 

[oilman]

how old is your system?

 

[wysokoa]

1 year old

 

[wysokoa]

A Plumber visited today and after some thoughtfull diagnostic found that the pipe work was wrong.

There is an Automatic Valve that directs water when both the Hot water 2 port valve and the CH 2 port valve are closed. Well this was in the wrong place and was creating a shortcut for the hot water, instead of going into the Cylinder, it was coming up, then back down to the boiler!!

The reason the system was worked in the passed (and is currently working) is by Closing the inline valve (a reg wheel on my system) halfway, thus creating more pressure to use the shortcut than through the system.

Hope this helps someone else.

Regards

Matt

 

[oilman]

There is an Automatic Valve that directs water when both the Hot water 2 port valve and the CH 2 port valve are closed. Well this was in the wrong place and was creating a shortcut for the hot water, instead of going into the Cylinder, it was coming up, then back down to the boiler!!

That is what it should do. If the HW valve is closed, it is because the hot water is hot or it is off, so no flow required.

The valve is a differential bypass valve and is set to operate at a defined pressure. What you have done id bodge it so it works, where as you should investigate the valve and cure the problem.

The plumber has misinformed you IMHO.

 

[Registered Gas Man]

Oilman like you I am stumbed by this post!!

I've read it several times and am still none the wiser

This is what I think he is saying: His sytem is an S plan

Hot water 2 port valve and the CH 2 port valve

and it has an auto bypass before the valves [ which would be correct ] so that if both valves are closed the pump still does its job and the pump shuts the boiler down.

But he also has a manual bypass that some plumber has now closed for him and the situation is resolved!!!???

But all that he needed to do, was set the Auto Bypass to the correct pressure setting???

 

[wysokoa]

I have to apologise, I am a total newbie and what is quite simple I have managed to confuse everyone.

The problem is that the Valve thing is after the T Piece and not before, we even went into a neighbours house to compare systems (as it is a new deveopment and all built by the same developer) and mine is piped differently.

The plumber is right, probably my explaination that isn't really good.


The water Hot Water from the boilder isn't going into the cylinder (which would be full of cold water as it is mains fed) because the valve is in the wrong place and it is an easier route to go through the valve rather than into the cylinder. The thing we have partially closed is the feed to the radiators (I think) with I also think makes the flow path to the valve more difficult than through the cylinder.

Sorry if this makes it no more clear.

Merry Christmas


Matt

 

[oilman]

I'm just as confused then, and I've had only two 1/2 small glasses of wine today and one was at lunch time.

Water comes from boiler.
Water gets to T branch
One way goes to cylinder valve and then to cylinder
Other way goes to manual valve and then to auto bypass valve

If I have understood correctly. This is the way it should be and the bypass valve needs adjusting.

 

[ChrisR]

Sounds wrong to me. Is "Valve thing .. after the T Piece " an ordinary looking gate valve with a "wheel" (usually red) head?

"The thing we have partially closed is the feed to the radiators". That one shouldn't be closed at all! The route through the hw cylinder is lower resistance than the rads circuit. The HW circuit often has a valve in it to slow the flow, though you need good flow for an unvented cylinder.

If you don't have an Automatic Bpyass Valve calibrated in bar or metres head then you're guessing, unless you set the system up with contact thermometers to check temp drops. ABV should be connected in parallel with the HW circuit and the rads circuit, and set to the right value to prevent damage being done to the boiler.

 

[breezer]

is it

exhibit "a"

exhibit "b"

exhibit "c"

exhibit "d"

_____________________________________________________________


just out of curiosity what is the advantage /disadvange of a gate valve v a ball valve like exhibit "a" v "d"

 

[oilman]

Just my opinion, there's probably other valid views. The gate valve is less prone to erroneous operation with many turns, can be set finer, restricts flow more at max open, can reseal leaking shaft. Ball valve, almost no flow restriction, quick operation (sometimes to wrong position, I've done it!!!) if shaft leaks it's a new valve, fits in smaller space.

If you are using a storage tank to fill a mobile tank, it's useful to have both in series, gate valve as main shut off, and ball valve as service valve which can be shut off quickly in the event of a leak.

 

[breezer]

thanks

 

[oilman]

Thats ok.

Can you help me? Where can I get pictures like this, and how do I get them into a posting?

 

[masona]

Right click on any picture you want to copy,then click on Properties (I have use the bottom picture of above as a example) copy & paste the Address then click [img ]http://w ww.s...space > w ww to stop it working,should be www

 

[oilman]

Many thanks. Simple when you know how.

Now, how do these boiler things work?