What cylinder and boiler with a Hwam Monet

[spwilko]

I'm looking to buy a Hwam Monet stove as it's contemporary looking and the back boiler is suitable for a pressurised system.

I intend to use a 200 litre dual coil unvented cylinder and replace my old combi boiler with a system boiler.

I haven't decided which boiler and cylinder makes would be best suited to this system so would really appreciate some feedback on these.

Thanks

 

[simond]

These type of stoves are dubious from a building regulations point of view in the UK when connected to an unvented cylinder.

Whilst they incorporate valving to prevent disaster, this type of control will probably not meet UK regulations.

Almost any type of system boiler and unvented cylinder will be compatible; the question is whether you are feeling lucky. The shops selling this equipment will tell you it is perfectly safe, but you will find them a bit cagey if you probe deeper regarding specific UK approvals.

We would not fit a system of this type unless we could see that the necessary UK approvals had been met. Any insurances backing up an installer could be invalidated, and what the retailer states will not count for anything when the building regs and HSE get involved.

I would suggest you find out exactly what approvals this unit has for connection to unvented cylinders in the UK before writing out a cheque.

Connection to a heat store such as one of the DPS units would be a much safer option and not require approvals.

 

[spwilko]

Thanks for the advice Simon

Simon

 

[Agile]

There is no need to replace your existing combi.

It can be used to provide DHW to the kitchen for example and the heat side can be used with the appropriate motorised valve just like a system boiler.

I will echo what Simon has said about the use of a solid fuel stove with an unvented cylinder.

Depending on the number of people a 200 litre may not be adequate during the summer when relying on gas heating of the upper coil as the volume of water heated may not be adequate for your needs.

Tony

 

[spwilko]

Thanks Tony
The combi is an ancient noisy Vokera which I'd like to replace anyway.
I have built a large extension (70m2) with underfloor piped heating so wanted to get a boiler rated for the extra requirement (although it's very well insulated).

I like the DPS idea. Is it possible to add a solar circuit to one of these?

 

[simond]

Yes, you can add solar, fuel burning stove and boiler.

See www.heatweb.com, XCel 2009 section.

We are fitting a DPS Pandora next week, coincidentally.

 

[Agile]

You 70m² of UFH has a heat input of only about 4 kW.

Your existing combi will be rated for at least 24 kW which will be more than twice your likely heating requirement.

Whilst a new condensing boiler would be a little more efficient, DP will tell you that an older Vokera is far more solidly built that any current boilers and properly serviced will give you many more years of reliable service.

The cost of fitting a new boiler will not be recovered from the small increased efficiency savings unless it lasts well over 10 years ( the normal life expectancy of current boilers! ).

Tony

 

[spwilko]

Cripes! So my old Vokera 24-96 shouldn't be scrapped just yet.

Need to rethink what to spend my money on

 

[spwilko]

I got a quote from the nice folks at heatweb and discovered the store would need to be 2m high, which is a non starter for my loft area. This was based on adding stove and solar to an xcel heat bank.
Their dps did seem a perfect solution which is a shame

What are the alternatives guys?