Heating system design

[dazzler9000]

Hi all, hoping somebody can help.

I had Homeserve out today, as I've just started a boiler and central heating contract with them. They sent their engineer to assess the boiler but declined to insure my Vaillant Ecotech plus 837, because the condensate pipe had previously leaked and showed rust residue in the chassis.

The boiler is currently showing no issues, but I suppose I should factor in a replacement at some point.

I'm hoping some pros on here can offer some guidance on a possible system replacement.

I have a 3-bed detached house. Currently, I have the gas boiler which heats the upstairs radiators and wet underfloor heating downstairs. I also have a log burner.

I see hydrogen boilers might be coming out soon, so I'm guessing these could be better for a 1960s poorly insulated house over heat pumps.

It's always bugged me that I can't utilise any of the heat from my log burner to heat water. Would I be best off getting some form of a thermal store to add to the new boiler, that allows for a feed-in from the log burner? Would I need anything else (I've heard the term back-boiler mentioned?). One problem I have is, that the roof height in my attic isn't that high. Most of the thermal stores I've seen from Gledhill are about 1700mm high, which wouldn't fit, although I did find this one which might fit - Gledhill Can you buy stubbier ones? Also, I'm clueless as to how may litres of storage I might need?

Also, I'd like to get solar at some point, so it would be good to also heat a thermal store from that.

Any advice on what to look at would be appreciated.

 

[oldbutnotdead]

If you can fuel your woodburner for free then it's worth the fair size investment needed.
Thermal store- 500 litres as a sensible minimum for that size place. Loft may not be the best place for half a ton of cylinder. This bunch Link are useful.

 

[dazzler9000]

If you can fuel your woodburner for free then it's worth the fair size investment needed.
Thermal store- 500 litres as a sensible minimum for that size place. Loft may not be the best place for half a ton of cylinder. This bunch Link are useful.

That would be a no then. We use the log burner for between 4-6 hours an evening and longer at the weekend but no, I don't have a free supply sadly.

No way I'd be able to house a 500 litre store, I was thinking I could at a push fit in the 210 litre....

Thanks for the links, I will take a look.

 

[oldbutnotdead]

You'll get a much better return on investment by upgrading the insulation as much as possible (300mm in the loft for starters).
Not all woodburners have a clip on back boiler option, you need to run the thing quite hard to get useful temperature in the store. The fuel consumption of your woodburner will increase if you are heating water as well (no such thing as a free lunch). Mine uses the equivalent of 3 good bags of logs a day (no I don't buy my wood in, I do use the bags to bring timber in from the store) to heat house and hot water.
If your heating system is pressurised (no tanks in the loft) it gets more complex and less easy to use the store as a preheat on the boiler primary, ditto on solar.

 

[dilalio]

First advice would be to not sign up to Homeswerve and to find yourself a decent independent plumber and heating engineer.

We are out there, you know!