Heat Bank/Thermal Store Recommendations

[KingGeorge]

I'm looking for recommendations for specific heat bank/thermal store products.

From reading around, I think my rough setup would be a pumped external plate heat exchanger for DHW, primary water in the cylinder heated directly by gas boiler and shared with CH. Cylinder size would be approximately 250-300L. Cylinder and boiler would be on ground floor, with F&E tank above highest radiator, so in loft or in top of a cupboard on top floor.

A rough indication of prices would be useful. I've heard good things about DPS, then realised they'd gone bust, though now I believe the products have been bought by someone else? I also read somewhere that they're a bit pricey, so it would be good to hear if they're worth it or not.

Thanks!

 

[KingGeorge]

*bump*

 

[Dan Robinson]

I have the DPS (Now Specflue) Excel unit in my house.

It is indeed very effective, but new very pricey for what it is.

Any particular reason why you want a heat bank?

Are you linking various heat sources?

 

[petit_pablo]

Get a boilermate

 

[Dan Robinson]

Or make me an offer for mine (seriously).

.

 

[KingGeorge]

Or make me an offer for mine (seriously).

Any particular reason you don't want it any more?

 

[Dan Robinson]

Got it for an experiment in boiler controls and weather compensation and data logging.

Finished all that now so would prefer the space as I do not need a vessel that size for hot water.

Contact details are in my profile if you're interested.

 

[KingGeorge]

Any particular reason why you want a heat bank?

I don't want an unvented cylinder (not simple to maintain myself). I don't particularly want a combi as it's a fairly large house (5 bed) and I prefer the idea of smoothing out demand with a thermal store.

The other option is a traditional gravity-fed system with pumps for showers but that has its own problems of course, though it is simpler to maintain myself.

As for heat bank (external PHE) vs thermal store (internal coil), I'm leaning towards having a coil now to reduce the reliance on pumps.

Are you linking various heat sources?

I'm not actually going link various heat sources immediately, though I do like having the option of doing that in future. Most likely we'll add a solar heat source, though I'd need to calculate how useful that will be in the UK.

 

[Dan Robinson]

Solar in the UK depends heavily on location.

We switched on 2 systems in a single house a few weeks ago.

Both 100 litre stores were up to full temperature by mid morning.

Not a particularly bright day in North London.

Panels set at a far from optimum angle.



Thermal stores do rely less on pumps, but they are more prone to scale and blockages.

A cheapy pump for the plate costs much the same as the a couple of doses of system cleaner anyway .

Can be changed in a matter of minutes too.

Not that I am in any way biased

 

[KingGeorge]

Solar in the UK depends heavily on location.

We switched on 2 systems in a single house a few weeks ago.

Both 100 litre stores were up to full temperature by mid morning.

Not a particularly bright day in North London.

Panels set at a far from optimum angle.

We're in North-East London, so that's encouraging! The roof I have in mind is pitched at 25 degrees, roughly south-facing. The angle is great for Summer, but maybe not so much for Winter.

Thermal stores do rely less on pumps, but they are more prone to scale and blockages.

A cheapy pump for the plate costs much the same as the a couple of doses of system cleaner anyway .

That's good to know. The external PHE seems preferable from a maintenance point of view. I don't suppose the pump costs that much extra to run anyway.

 

[Dan Robinson]

The hot water shunt pump on mine uses 93 watts.

The heating pump you use can be one of the variable speed jobbies.

There is a dedicated solar coil too so the glycol solution doesn't mix with the thermal store water and can be retrofitted without affecting the rest of the system.


I wouldn't even factor the winter into your equations on the solar thing.

Interestingly or not, they say to run the store at 85 degrees.

Twaddle. At the moment mine is set to 60 degrees with an input temperature of 70.

The bath fills perfectly with 47 degree water.

Boiler condenses beautifully for one long continuous burn.