Unusual Heating System - Expert Advice needed

[Jmines54]

I'm struggling to make a central heating system work. The problem is, I've got a stone house with the plumbing already installed and it's tricky to add new pipes. Essentially I've got 2 floors and 4 radiators downstairs and 3 upstairs. There is sufficient pipework to run 3 single pipe circuits with 2 or 3 radiators on each one. The expansion tank is high up and the expansion pipe can be the first thing on the hot circuit, but is reached by 3m of pipe under a tiled floor from the boiler, which is on the 1st floor. I have tried to puzzle this out myself, but have had limited circulation, airlocks, and worry about safety as wood burning stoves can't be switched off in a hurry! The diagram attached shows my best shot at making this work and is a configuration I haven't tried yet. I've put the pump into the cold side, so I can have a free run on the hot side to the expansion pipe. I am also concerned about having to route the hot supply down into a manifold on the ground floor and back into each of the 3 single pipe circuits. Will this system work if I connect as per the diagram?

 

[Norcon]

A stove on the first floor is a bit unusual.
Pipes coming out the bottom even more unusual. I think you need to get another fag packet and maybe start again.
Post up an image of the system exactly as it is at the moment and not how you think it should be!
Only then will you be able to get an answer. I'll delete this as soon as post up the new image.

 

[Jmines54]

A stove on the first floor is a bit unusual.
Pipes coming out the bottom even more unusual. I think you need to get another fag packet and maybe start again.
Post up an image of the system exactly as it is at the moment and not how you think it should be!

Thanks for your comment. OK, will try to draw it as it is.. The stove has a back boiler at the top with the flow and return straight off and down to connections in the floor. There's no easy way of putting the stove downstairs, due to the layout of the house.

 

[picasso]

 

[hazetimesfive]

pomp and circumstance. lol

 

[Jmines54]

Here's the diagram of a back boiler system in a stone house. It is far from ideal and probably dangerous, so I will not be running it like this. The main problem is that the stove has to be on the first floor and it is hard to add pipework as it is part of the building. It would be easy to get the expansion pipe close to the boiler and before the pump...a bit more difficult to supply cold from the expansion tank, without routing through the downstairs cold manifold. I'm also stuck with 3 single pipe circuits, unless I start drilling holes in thick stone walls and putting pipes all over the place! I'm looking for feedback on if this can me made to work over the 2 floors of the house, as in the diagram and what changes are needed to ensure efficient circulation and safe running of the boiler.

 

[Norcon]

Looks like something that could explode.
Certainly wouldn't be using it.

 

[Jmines54]

That's why I am not using it. It would be really fantastic to receive a constructive comment on how it could best be sorted or if it really isn't possible to fix over 2 floors without re-siting boiler etc.

 

[Norcon]

First thing it needs is a feed, expansion and open safety vent arrangement as per BS 6700.

 

[Jmines54]

OK, thanks. The first diagram I posted attempts to do just that. Here is an excerpt from the regulation and my suggested diagram seems to meet it. I have a connection straight through from the boiler flow side to an open vent and the cold feed goes straight to the boiler and the pump is in the cold feed line. This should ensure that whatever happens, water is supplied to the boiler and if the water boils it should vent OK. What about running radiators below the level of the boiler please?
5.3.5.6.1Vented primary circuits
Vented primary circuits shall have a vent route connecting the flow connection on the boiler to the vent pipe outlet above the expansion cistern and a feed water route from a point near the bottom of the expansion cistern to the return connection on theboiler.
Except as specified in this subclause, these routes shall be independent. It is permissible for both these routes to be incorporated in parts of the primary flow and return pipework, but the vent route shall not include any valve, pump or any impediment to flow whatsoever.
Where the design of the primary circuit so dictates, it is permissible to include a circulating pump and its associated isolating valves in the feed water route. A feed and expansion cistern for a double feed primary circuit shall accommodate 4% expansion of the volume of the water inthe circuit. Except for a circulating pump and its associated isolating valves and except for a servicing valve, both fitted only in the circumstances specified in this sub clause, the feed water route shall not include any valve, pump or any impediment to flow what so ever. Where the vent route and water route are combined, the boiler and primary circuit shall have the protection specified in 5.4

 

[Norcon]

You seem intent on sorting this out yourself.
Why add too the bodgework?

My advice is to employ a competent plumber before the place is blown up.

Is this actually your own installation?
If not then were you aware the certificate of compliance was not completed when you acquired the property?

Hetas wrote

If the HETAS Ltd Certificate of Compliance is not provided, is not completed correctly or the Certificate is returned late then there will be no notification of the work to the Local Authority by HETAS. This would in fact mean that the law has not been complied with and can cause difficulties when selling a property and potentially void a household insurance policy.

 

[Dan Robinson]

Vented primary circuits shall have a vent route connecting the flow connection on the boiler to the vent pipe outlet above the expansion cistern

Read that bit carefully then look at your picture.

 

[Jmines54]

Vented primary circuits shall have a vent route connecting the flow connection on the boiler to the vent pipe outlet above the expansion cistern

Read that bit carefully then look at your picture.

OK, thanks for the comment - it looks like you are referring to the (dangerous) way it is now....so does the first one I posted i/e. suggested layout meet that requirement?

 

[Onetap]

First thing it needs is a feed, expansion and open safety vent arrangement as per BS 6700.

That is the main problem. That alone would be reason not to use the system until you have rectified it.

If you've bought the house recently, the apparent lack of installation documentation by a competent (HETAS) installer should have been noticed in a survey. The installation might be illegal, meaning there are other dangerous details (fresh air supply, flue, hearth, lack of a heat dump radiator with a gravity primary circuit, etc..) which you haven't noticed yet.

IMHO, I don't understand how it could work properly since there will always be circulation through the stove. This will cause a big heat loss up the chimney when the boiler is working.

The radiators on your sketch seem to be fitted with reverse return pipework, an unusual detail that might suggest the work was done by someone who knew something about it. Could you have missed some of the installation or misunderstood the arrangement?

 

[Norcon]

It's a constant race between making things idiot-proof, and the universe making better idiots

In the context of this thread.
Very true.