And I have. As per previous posts I tested it with my boiler and savings- zero. Post #72
Heat Pumps and Zones (or not?)
- Thread starter Ivor Windybottom
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Leaving aside energy savings, I can say with 100%, certainty that our house and lifestyle means zoning is essential (in our case, I'm working towards per-room as other works permit.) Thing are so variable that any setup you might do with a last century approach of thermally balancing the system is unlikely to last long.
For example, the lounge needs heating in winter, but when the sun comes out it overheats even when other rooms (especially downstairs) are cold.
For example, the lounge needs heating in winter, but when the sun comes out it overheats even when other rooms (especially downstairs) are cold.
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Shading issue?
I was just waiting for the nit-picking on my statement!
It's an entirely brick-built bungalow. So there's pretty good insulation between rooms courtesy of 6" of plaster and clay. Rising heat eventually just leaves the building, it doesn't heat any rooms above. This doesn't change with or without zones. We do shut doors between rooms anyway, so cooking smells don't end up in the bedrooms.
We had no heating in the bedrooms but the doors open the other day. It was still noticeably cooler in there.
My office is an extension annexe, it's on the other side of a cavity wall from the rest of the place. It's basically a semi-detached separate building. I shut the door at 5pm and don't go in there until 9am the next day. It would be just insane to heat the place in an evening.
Some houses are more or less suitable for zoning. Don't get obsessed about heat leaking between zones, obviously it happens. But if the unheated rooms are cooler than the heated ones then you're very likely to be saving money.
We haven't tried without zones, as this is how it was all installed. I could manually switch them all on at once if I really wanted but it's obvious that this would be just a waste of money.
I'd recommend zones to anyone installing a new from-scratch heating system. It will cost a bit more but you'll save every day after. Expect resistance from the plumber, self-appointed experts and armchair scientists on the internet as I got. There's a lot of misinformation around, plus I suspect that plumbers are all too eager to embrace a theory that means they'll have less work to do.
It's an entirely brick-built bungalow. So there's pretty good insulation between rooms courtesy of 6" of plaster and clay. Rising heat eventually just leaves the building, it doesn't heat any rooms above. This doesn't change with or without zones. We do shut doors between rooms anyway, so cooking smells don't end up in the bedrooms.
We had no heating in the bedrooms but the doors open the other day. It was still noticeably cooler in there.
My office is an extension annexe, it's on the other side of a cavity wall from the rest of the place. It's basically a semi-detached separate building. I shut the door at 5pm and don't go in there until 9am the next day. It would be just insane to heat the place in an evening.
Some houses are more or less suitable for zoning. Don't get obsessed about heat leaking between zones, obviously it happens. But if the unheated rooms are cooler than the heated ones then you're very likely to be saving money.
We haven't tried without zones, as this is how it was all installed. I could manually switch them all on at once if I really wanted but it's obvious that this would be just a waste of money.
I'd recommend zones to anyone installing a new from-scratch heating system. It will cost a bit more but you'll save every day after. Expect resistance from the plumber, self-appointed experts and armchair scientists on the internet as I got. There's a lot of misinformation around, plus I suspect that plumbers are all too eager to embrace a theory that means they'll have less work to do.
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Per-room would be everyone's theoretical optimum. But it would take a lot of pipework and equipment, and timers and settings could all get complicated.
We have...
Work - my work annexe including a shower room
Rest - two bedrooms
Play - Living, Dining Kitchen, Hallway
Study - My other half's work room (plus the main bathroom next door)
I don't think I'd want to break things down any further.
All radiators have TRVs, the ones in the rooms with the controller are set to max.
Hence the popularity of combi-boilers, also popular with developers who can shave the space for a cylinder off the size of each property.
Doesn't need a lot of pipework - you can do it with actuators on each radiator, replacing the TRV heads on an existing system.
I have long term plans for something better, but in the meantime I have a mix of hardwired and wireless* programmable stats controlling a thermo-hydraulic head on the radiator and running the pump. I've a thermal store and modulating pump so have no worries about dead-heading the pump, but for a more conventional system you'd need a bypass to keep the boiler happy until the rad valve opens.
* I get one stat and two receivers. One receiver controls the rad valve using the nearest convenient socket, the other controls the pump. I'll be replacing these with hardwired as/when I'm in a position to chase walls etc. (i.e. next time we are decorating.)
I have standalone stats, but there's nothing to stop you using something like the Heatmiser ones which are hardwired, but also connect to WiFi (via a hub IIRC) for "smart" controls.
If you did want to centralise the valvework, many properties use microbore and one or two manifolds. If going that way, no extra pipework but you do need room for all the valves.
No, large south and west facing windows - plus Velux windows. The Velux in north facing roof isn't a problem, but the south facing one adds a lot to the insolation - we've added blinds which help a lot with that.
So in winter, room tends to be cold as all the heat buggers off into the high vaulted ceiling - and when we bought the house, it had a crappy "designer" rad that put naff-all heat out. In summer, all that insolation turns it into a solar powered oven. But downstairs generally doesn't get much insolation, so tends to be cool(er) even in summer. I'm sometimes mused fitting aircon in the lounge rigged up to put the heat into the thermal store so it can be used downstairs.
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I should have been clearer, and asked if it was a brise-soleil issue (I have one of those; ie the lack thereof, and 6sqm of roof glazing in a 16sqm room)
Some house occupants love that the loft office gets into the 40s, others not so much
Sounds familiar, and so many times I’ve thought about buying a small ASHP and sitting it in the office, stashing the solar gained heat into the DHW, not because I think it will be massively more effective to do so than the one outside, but because it would cool the place down as it went. The outside ASHP will cool, but then I’m just paying to dump heat outside after a few lacklustre design decisions brought it in
grilles that let low winter sun in but reflect high summer sun away, mounted to the glazing would be great, but too much else on the list.. All we have now is a massive fan to circulate warm air down if required or as a purge if we open the right doors
Some house occupants love that the loft office gets into the 40s, others not so much
Sounds familiar, and so many times I’ve thought about buying a small ASHP and sitting it in the office, stashing the solar gained heat into the DHW, not because I think it will be massively more effective to do so than the one outside, but because it would cool the place down as it went. The outside ASHP will cool, but then I’m just paying to dump heat outside after a few lacklustre design decisions brought it in
grilles that let low winter sun in but reflect high summer sun away, mounted to the glazing would be great, but too much else on the list.. All we have now is a massive fan to circulate warm air down if required or as a purge if we open the right doors
My working background is in electronics. The last place you want to put electronics or batteries is attached to a radiator, it's well outside of the temperature range of commercial components, and I'm certain they won't be using mil-spec components, as I've seen the price of them. I wouldn't even consider them.
Our system is not dependent on any batteries or the internet. The app is an added extra, but if the company who makes it goes bust and shuts down their server it will all still work.
When there was a recent Amazon Web Services shutdown, people using various home automation couldn't even switch their lights on.
Microbore was a terrible idea for gas boilers, I don't think it works at all for heat pumps. You need to shift a lot more water around the system as the flow temperature is lower. I'm sure it could be done, but I doubt it would work well at all.
Our kitchen/diner radiator is at the limit for a 15mm pipe, the plumber said they're now starting to make some that require 22mm pipes.
I don't have electronics on the rad - just a thermohydraulic actuator (mains at the moment) - they are a wax capsule with a heater element.
The electronics shouldn't get that warm unless it's a really bad design. There's actually a relatively poor thermal connection between the valve attachment and the gubbins - it's a design consuderation to make it that way as it has to sense air temperature in most designs.
Too many people never think about that.
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