New heating system being installed

[Funny Lingus]

Interesting, storage heaters ripped out and new electric boiler with air transfer heat pump mounted in garden.

[Dave Plowman (News]

I'd guess anything better than storage heaters.

[Funny Lingus]

They were working fine......just a huge waste. It will take centuries before any green savings are made, if ever, especially after manufacture of all materials used

[NY]

Apart from ducted-air/ My parents' house, built in 1972, had gas-fired ducted-air and it was very underwhelming: a vague trickle of tepid air out of the ducts, wafting dust everywhere. The house was always cold.

Storage heaters fail because they give out their heat too quickly in a morning (even when the heat output control is turned right down) and there isn't much left by the time you get home from work in an evening. Also there is no way of programming the heat output to increase shortly before you get home from work so the house is up to temperature. My first house had a single storage heater (the house was open-plan so the heat rose from the living room to the bedroom) but it also had a couple of panel radiators (lounge and bedroom), supposedly just to provide "supplementary" heating, though I needed them most of the time.

When my wife and I were looking for a new house, we saw one which had central heating with an heat-transfer pump and radiators. The house was perfectly warm, but we both agreed that the constant whine of the stale-air extraction pump, audible in every room, would have driven us mad very quickly. The boiler and floor-to-ceiling hot-water cylinder occupied most of the utility room, and that was excluding the heat-exchanger (on the wall outside) for extracting heat for the ground.

[Davey]

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For the thirty-odd years that I lived in America, the forced air heating and cooling systems were always fine. Having done it that way for years and years, they probably knew what to do. A heating system could always have Air Conditioning added, and believe me, you need it over there. In all of the places we lived, and there were many, none ever had a problem keeping warm. Often, the forced air fan was a bit noisy, but we got used to it, it only came on when calling for heat. The house we rented in Kansas City also had a 'whole-house fan', a giant louvred extract fan mounted in the ceiling, and venting into the loft. Adequate loft ventilation, always a given in American houses, took care of the hot air. The fan could cool a hot house down in ten minutes, you just needed earplugs while it was running.

[T i m]

<snip>

So you mean 'some / the current range of storage heaters fail ...' as it shouldn't be beyond the abilities of man to make them better? ;-)

See above.

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My storage rads are 'smart' in that they turn on automatically, after receiving power (E7), but only when they determine that they still need a recharge to be able to absorb the maximum required input to (predictably) last them though the day.

No predictive system is ever perfect of course but they generally did a good job, especially when the temperature was changing smoothly.

eg. In the summer they didn't come on at all, in spring / autumn they might be on for a while towards the *end* of the E7 cutoff time (so lasting best throughout the day) and during the winter they were often on most of the E7 period and generally kept the room warm for the entire day (correct size / room match, good insulation and efficient thermostatic control).

Unfortunately, something went wrong in them all after a good few years (15-20, I suspect the main relay) as they would repeatedly 'clonk' when they should have just pulled in the once. I did track down a replacement relay but it wasn't cheap and the postage from abroad made it even more so. Things may be different now and so I may re-visit that one.

Alternatively I could now probably integrate them into my Home Automation system and make them even more 'intelligent. ;-)

Internal temperature probe measuring the core. External probe for the room, controlling a servo on the heat outlet control flap and a solid state relay for the heater element (it doesn't matter if it gets warm). ;-)

Cheers, T i m

[Dave Plowman (News]

I suppose someone somewhere was pleased with storage heating. In the same way as someone somewhere wins the lottery.

A decent heat pump system should have much lower running costs than storage heaters. Which in the UK are about the most expensive to run house heating.

[RJH]

Interesting. My sister is thinking of getting a ground source pumped system. Are there any decent sources of experiences of them in use? Hadn't thought of the pump before . . .

Also, does the cooling of the ground have any effect? I'd have thought flora/fauna would suffer . . .

[Tim+]

No experience what what I have read is that you really need quite a lot of ground OR you go for bore holes, both of which are expensive. For most people , ground source just isn?t economic due to lack of ground or very long ROI due to high installation cost.

Cooling of the ground (and diminution in efficiency) can be an issue if you don?t have enough area or depth. Dunno about effects on flora/fauna.

Tim

[Theo]

'Stale air extraction pump', so you mean a MVHR (mechanical ventilation) system? Or an ASHP (all the air stays outside)? MVHR typically has ducts inside with fans in them. It sounds that's a ventilation system not a heating system? (You can get MVHR integrated with an ASHP but only to a limited heat output - which might be OK for small super-insulated new-builds)

(the forum is a bit new but it's growing) GSHP should be very quiet given it's just pumping fluid into the ground, unlike ASHP where it's pumping air through heat exchange fins. It then feeds into radiators or UFH - like any central heating there are water pumps. Some are quieter than others (I heard Wilo recommended).

The ground is a buffer between summer and winter. You extract heat from the ground in winter, and the sun recharges it in summer. If you don't size things right it doesn't recharge enough and it's harder to extract in future winters. I don't think flora minds too much because most of the growing is in the summer, and most fauna doesn't go down far enough to notice (unless you have digging rodents), although I couldn't comment about earthworms.

THeo

[Andrew]

If you are on heavy clay soil then that is the best type for a ground source heat pump where the primary loop is not far down but spread over a large area.

You only get water at 50C at most, out of it so it works best in new-build houses with underfloor heating and loads of insulation. What it won't do is give you lashings of hot water as you would get with a gas/oil boiler delivering water at

80 to 90C.

Also, remember the most effective refridgerants have been banned so it is slightly crippled, efficiency-wise from the outset.

[T i m]

I was party to various stages of a mate installing a GSHP system himself (he's a Heating Eng) from getting the portable rig into the back garden, to boring the holes, running the pipes back to the manifold and hooking up the pump itself.

This was in the early days when GSHP was supposed to be the new panacea of home heating but 1) the GSHP was something he imported directly from China, had little in the way of instructions or support (and he never got working, the last I heard) and 2) if he had going it going and it had worked well, he would have offered it as an installation service to others (and hence why he chose to import directly as it meant better margins, had it worked etc).

It's quite possible that assuming it does actually work (functionally), someone who knows what they are doing could fix / commission it for him and at least he could be using it himself (even if that meant replacing any control electronics etc).

It was interesting how they dealt with the pipes. These were vertical deep bored (I think they went down 10m or so) and the slurry that lubricated the drilling also stopped the hole falling in once drilled. Then after sounding the final depth, two pipes were cut to length for each hole and fitted a metal (I think) 'U bend' type fitting to the end of both then they were fed them down the hole, displacing the slurry. Two 90 Deg fittings on the top ends took the flow / return along trenches in the garden and into the garage / manifold. The pipes were then flooded with a suitable mix and the system pumped round. I think he had 3 (possibly 4 holes).

Cheers, T i m

[Brian Gaff (Sofa]

Bit odd. I have storage heaters, pretty basic technology really, but does the job. Brian

[Funny Lingus]

What an abortion:-

[Adrian Brentnall]

We have a ground-source system installed here in South-West Ireland - replacing the oil-fired boiler that was installed when the house was built..

The heatpump lives outside in my glass workshop, and there's 3 or 4 100m coils of black plastic pipe in four separate trenches under the polytunnel.

In an ideal world, they say that the hot water (which isn't as hot as you get from a conventional CH boiler) should be fed into wet under-floor heating (so the floor-slab becomes a huge storage heater) - but, as we were retro-fitting, we used the existing rads instead.

System works well, pretty-much zero-maintenance (had to fit a new motor-start capacitor - ?15) about three years back - but apart from that it's run without issues for the last 15 years.

No noticeable effect on the local environment - there's a lot of heat stored in the ground, and our coils are in some very soggy ground adjacent to a stream - so this all helps.

[RJH]

That's a lot of pipe. I'd guess the garden's about 200m x 100m - not sure if that's enough. But her husband's an environmental scientist, so I'd guess he knows what he's doing.

Interesting, thanks. I was thinking about that whole subterranean life cycle and any knock-ons. But to know would need some pretty involved research I'd have thought.

[Andy Burns]

I have an acre plot, and due to limitations such as not close to boundary, not near maintained watercourse, not under tree shade, not under house it's borderline whether enough slinkies can be installed, and have heard a horror-story of a local install that turned out to have an undersized collector.

Those factors, along with the high price, and the moving goalposts of the RHI mean I probably won't fit heatpump as part of build, but LPG boiler with UFH, but may fit GSHP with boreholes "later"

[Adrian Brentnall]

Yes - lots of pipe.. As luck would have it, there was some significant earth-moving going on at the same time - so the cost of the trenching got absorbed into that.

In tight spaces, they recommend a borehole rather than trenches and pipes.

Yes - could be quite a research project... Most of the coil area is covered by our polytunnel - so I guess that contributes to replenishing the heat a little..