Size of pipework and need for manifold

[paul123]

Hi,

This is my first post so please forgive any errors.

We are installing a woodchip boiler to replace our old oil boiler and have a problem connecting it to the existing heating circuits. We’ve tried to get a plumber but everyone gets scared off when we say it’s a woodchip boiler.

Anyway the old oil boiler had inch and a half flow and return connections which reduced immediately down to inch and a quarter. There was an inch and a quarter Grundfos pump on the return. The flow and returns in inch and a quarter then divided into 28mm for downstairs (13 rads) and 22m for upstairs (5 rads).

The new woodchip boiler also has inch and half flow and return and I just want to copy what we had before. Because its solid fuel, we need to fit an ESBE VTC511 mixer valve. This only opens the central heating return flow when the temperature is over 55 degrees to protect the boiler. I think that’s fairly straightforward.

However, the supplier of the ESBE has told me that I should install an inch and a half manifold and run inch and half from the boiler to the manifold, including an inch and a half ESBE valve and a new inch and a half pump. The heating circuits then go off the manifold. I can’t see why I need this manifold. He says it is to “balance the system. Why can’t I just repeat what was there before, but with the mixer valve? Attached is a drawing of my proposal.

Help please – do I really need this inch and a half manifold?

 

[Puddle]

Well you have to follow manufactures installation requirements which I presume your supplier is relaying, the argument that it should work ok as it did before does not really hold,after all we are useing a completly differant bit of kit, maybe a call to the actual manufacturer will help, at least you may be able to reuse the 1 ¼” pump, but nobody is going to advise you to go against suppliers or manufacturers instructions
As so often happens the time you spend trying to get around the siduation the modification to pipework could probably have been none

 

[kenneth11]

QUOTE=paul123;31442]Hi,

This is my first post so please forgive any errors.

We are installing a woodchip boiler to replace our old oil boiler and have a problem connecting it to the existing heating circuits. We’ve tried to get a plumber but everyone gets scared off when we say it’s a woodchip boiler.

Anyway the old oil boiler had inch and a half flow and return connections which reduced immediately down to inch and a quarter. There was an inch and a quarter Grundfos pump on the return. The flow and returns in inch and a quarter then divided into 28mm for downstairs (13 rads) and 22m for upstairs (5 rads).

The new woodchip boiler also has inch and half flow and return and I just want to copy what we had before. Because its solid fuel, we need to fit an ESBE VTC511 mixer valve. This only opens the central heating return flow when the temperature is over 55 degrees to protect the boiler. I think that’s fairly straightforward.

However, the supplier of the ESBE has told me that I should install an inch and a half manifold and run inch and half from the boiler to the manifold, including an inch and a half ESBE valve and a new inch and a half pump. The heating circuits then go off the manifold. I can’t see why I need this manifold. He says it is to “balance the system. Why can’t I just repeat what was there before, but with the mixer valve? Attached is a drawing of my proposal.

Help please – do I really need this inch and a half manifold?[/QUOTE]



Hi i have installed some wood pellet stoves and have only used inch pipe work what size is the boiler

 

[Puddle]

Would have thought connecting 28mm to a stove ,it would be a very small output model ?

 

[paul123]

Thank a lot for the replies. Sorry for the confusion.

It is not a stove. It's a 60Kw boiler. The manufacturers are Austrian and don't have any instructions for the heating circuits except they say that the return temp must be greater than 55 degrees. I've done this with a mixer valve.

The advice I received wasn't from the boiler manufacturers. I certainly wouldn't ignore their advice. The advice I got was from the chap supplying the mixer valve. He is the person telling me I need inch and a half pipework and a manifold. I've no idea what experience he's got, but it's probably more than me!!

Thanks.