Heating a large period house

[Flyfisher]

There is absolutely no reason whatever to have a well insulated house feeling "stuffy & vacuum sealed". There is absolutely no reason for a well insulated house to overheat in summer. I'll take my £100 annual heating bill any day, thanks, whilst enjoying a well ventilated even-temperatured 300 year old cottage.......

Could you explain the details behind how you have achieved your £100 annual heating bill and how something similar could be retrofitted to other period properties?

 

[MikeG]

One day (but.......whisper it...........it features lots of insulation). It's normally £70, but last winter here was colder and longer than for many a long year.

 

[fernicarry]

Cast iron rads look right, especially with brass valves.

Our downstairs zones are plumbed back to a manifold hidden in the kitchen. So we have plain brass valves on the rads and all the switching is done with electric heads at the manifold. Same kit as used for UFH. Had the Energy Saving Trust guy freaking out, no heating controls!!

Upstairs we have electric heads that just screw on in place of the TRV's but this does require a cable run to each radiator position. You can get wireless and battery operated heads too, but I'm old school hard-wired for everything. In the bathrooms the TRV's are hidden under the bath or in the cabinets so as not to spoil the look of the towel radiators.

Was thinking about the balancing thing. It does matter to an extent that you don't want one zone dominating and stealing all the heat from others if the flow is unequal. Even then so long as the emitter is big enough that zone should eventually reach its set temp and give way to the others. With the central manifold each zone gets its own pipe runs so each tends to get a fairer share -- star rather than bus topology. Even upstairs we haven't balanced the system, but then we also tend not to run all zones at the same time.

Ideally the heat you put in should just match the heat you lose so the system (zone) stays in a nice steady state without cycling on and off. That's the principle of weather compensation and I suppose balancing as well. In practice there are just too many variables and each zone tends to respond differently, even at different times of the day as the solar gain varies. One thing I would like to play with is altering the circulation temp according to outside temp.

Changing to variable head pumps really reduced the noise in our system when demand is low. And consume much less electricity if the display on the front is to be believed. Another reason for using the thermal store is that most boilers can't modulate down to a low enough level to power just one or two radiators so they will cycle on and off.

One of the reasons for deciding to use a modern home automation system is that it can make use of smart thermostats and sensors in each room and only heat the rooms that are in use.

If you're thinking of having the heating come on and off in response to occupancy sensors I don't think you'll get the responsiveness you expect. When I first put in our system I went a bit mad turning it down when we went out for a couple of hours and up again on the way home. It cools down plenty quick when you're not there but it takes a fair while to pick up again. In practice you really need to keep it ticking over programmed for your expected occupancy. Same reason I can't see Nest-type thermostats being of any benefit.

I was actually looking into boilers and how to control them from my home automation system. And if you have an OpenTherm compatible boiler, or a Bosch EMS boiler, then I did find ways of controlling them.

With the thermal store you just want to stuff as much heat as possible into it (and keep it there). The clever controls would be on the delivery side, zones, circulation temperatures etc. The combi isn't a good match because its just not programmed for heating a hot water tank and thinks the big radiator must have shutdown because the water coming back is nearly as hot as the water it sent out. Its been tweaked as much as we can to minimise the effect. I suspect it doesn't have too much longer to live so I won't feel too bad about chucking it and replacing.

Opentherm, from my understanding, is more about matching the boiler output to the demand on the delivery side. Opentherm stats kind of ask for an amount of heat to be sent into the system to compensate for what the stat calculates is being lost. How this would work with multiple zones I have no idea and it would be pointless with a thermal store sitting in the middle of it all.

 

[88v8]

I've also seen quite a lot of refurbished cast iron radiators advertised. Do you have any experience with refurbished ones? Is that a good route to take if I can find a reliable place to buy refurbished ones?
Also, are you the same 88v8 that posts on the Fool?

So long as they've been pressure tested, I would have no worries. Check that the air bleed screws are present and not rusted or rounded off. Some rads have the bleed screws cast in, some have them in the end tappings.

When I installed my systems, there were no new or recon iron rads. I put a small ad in the local papers offering £10 each for old rads, and waited for the phone calls. The challenge then was ascertaining what style they were and what size they were without having to go and look. And then, went to look, hoping that they weren't off direct systems and furred or rusted or both. In that way I rounded up two houses-worth of rads, a heated towel rail, and a never-installed cast-iron loo cistern from a retired plumber.

Wasn't so easy to find legless rads second-hand. In the end, I had to buy some with legs to get the right sizes so the system was balanced. One should not have to do too much balancing with the lockshield valves if the rads and pipes are the right size.
To hang the legless on the wall I used coach screws in No 20 fibre Rawlplugs.
Brackets like this, except I had to have them made.
https://www.castironradiators.ltd.uk/steel-cast-iron-radiator-bracket-42636-p.asp

Buy the rads before running the final pipework. Not all rads have the same dims. I recall that Crane were the nicest quality, they were 2.25" wide each section. Ideal were more readily available but the castings were not as crisp. They were 2" wide per section, so Crane and Ideal were not interchangeable.

We had two rads that leaked, one was a six-column that we had lugged upstairs, it eventually leaked between two sections when everything got up to temp. Lowering it back down the stairs on a plank, on the end of a rope, it got away from us - it weighed over 200lb - and nearly took out the balusters. I replaced it with a 12-section four-column, and we had to take up the finished floor and redo the pipework.

It's probably not a good idea to re-use user names

Ivor

 

[skier-hughes]

We have about 300m2 to heat and have an oil fired rayburn in the kitchen which is turned on when it gets cold and off when it warms up in the spring, as it is an old wick fired version. It is great for cooking and keeps the kitchen nice and warm. I'd not get rid of it. I did consider changing to a jet burner, but for the cost of conversion I didn't go that route with too many other things demanding buying. The rayburn is stand alone, kitchen only.

So you would recommend just keeping the Aga then, and adding a gas hob for non-winter use? Yes, we use induction hobs and a combi oven, grill microwave machine for the summer in place of the rayburn

We have solar hot water system which heats a 1000l buffer tank and 200l DHW tank and keeps us in hot water from around May to September.

I'm quite keen to get a solar hot water system if I can get consent for placing it somewhere. How large a surface area of collectors did you need for your setup?
We have tubes for DHW, 50 of them, which on our roof look to be about 10 sq metres.

Last year we had a LPG tank and boiler fitted, replaced all of our old radiators for new ones and installed the Genius Home Hub smart heating system. This also connects to the buffer/dhw tank and took a lot of working out how to make it all work properly, but we had a fantastic plumber and lots of help from Genius so that the gas boiler didn't always come on when a radiator called for heat, as when the wood burner is going we didn't want it to overheat, (there are plenty of safety valves etc in place).

The new rads warm so quickly and are so much more efficient we do not regret having them in the house. The genius system allowing us to heat individual rooms is brilliant and has saved me loads of wood. The gas is just idyllic, we are on our way home at night and turn heating on, tell it to use the gas and we have a warm home when we arrive, instead of getting home, lighting fire and pumping loads of wood in and going to bed before it's really done anything apart from take the chill off the whole house.

That's great to hear that the Genius Hub is working out for you. It sounds similar to what I plan to do with my home automation system. Are your new radiators steel or cast iron? New steel, I went for efficiency and as we had had older style steel rads in place for the last 12 years we are used to seeing them. No rad is period to our 500 year old house, so we went for what we wanted.

I looked into a pellet boiler, but the cost of pellets was the big con. I looked at commercial log burners, but size and the need for pretty regular sized logs was the con. The wood burner won as we have loads of trees we can fell, a friendly arborist who drops trees off for me to cut and chop so most of our fuel is free apart from time, which luckily I have plenty of.

Once I've moved I guess I'll have to start asking the locals what kind of fuels are readily and affordable available. I'd do it before you move

Thanks for all the info.

We have a worcester bosch system boiler and it works fine, heating the 1000l buffer tank and or the rads. As when the rads call for heat, it just turns on and lovely warm house.
I don't have the room sensors, just opting for wireless valves. Most of the time we just turn them on and off using the app, takes 20 seconds, in a big house walking to the thermostat and turning it up would take longer

Can't remember if I said, we also have a 4kw solar pv array and that covers all of our south facing roof with the tubes.
We aren't listed, so have no LBC worries.
When it all first went up, you could argue it looks a bit odd, but the house has been worked on so many times it has concrete tiles, blue, red rosemary tiles and some other sort of tile, so the roof looked odd before!

 

[fernicarry]

I don't have the room sensors, just opting for wireless valves. Most of the time we just turn them on and off using the app, takes 20 seconds, in a big house walking to the thermostat and turning it up would take longer

Our roomstats are on an app as well. Heatmiser. We have a touch screen in the kitchen too. And one day I'll reverse engineer the system bus and hook them into my imagined 'whole house' control system. Open bathroom window -> zone goes on set-back for 30 mins. Fully arm the alarm -> heating goes into holiday mode.

 

[ElectronicFur]

I'd do it before you move

Too late, we moved in last week, hence the radio silence.

Very exciting to finally be in, after first seeing the house exactly a year ago.

But unexpectedly my first job is to deal with a flea infestation :shock:

Fleas all over the house. Previous owners had pets.

Luckily the fleas don't seem to like me and the kids. The missus it turns out is a flea magnet though, so my life is a misery until I sort this out. Cans of Indorex at the ready for tomorrow morning. Hopefully it will also sort out the carpet moths.

And then I can get back to planning the heating again.

 

[Kearn]

Hopefully it will also sort out the carpet moths.

I wish you more luck than we had with various potions, powders and perseverance....! They are hungry little buggers, who only seem to stop munching carpet to reproduce. A lot.

We did find a great method of getting rid though, just wish I'd pulled up the inappropriate carpets we inherited much sooner than we did!

 

[skier-hughes]

In a previous house we also pulled up all the carpets as we had the most tremendous flea invasion, the house had previously been rented out to someone with plenty of dogs and had stood empty for two years while legal wranglings took place.

 

[MatthewC]

Assuming that your property has a ventilated roof space, I would invest in some thermafleece or similar to lay across the joists. I am convinced that it has the upstairs of this house noticeably warmer - heat rises and then gets trapped (or at least finds it harder to disappear!).

Matthew

 

[ElectronicFur]

I wish you more luck than we had with various potions, powders and perseverance....! They are hungry little buggers, who only seem to stop munching carpet to reproduce. A lot.

We did find a great method of getting rid though, just wish I'd pulled up the inappropriate carpets we inherited much sooner than we did!

Do you mean you only sorted the carpet moth problem out by getting rid of the wool carpets then?

At the moment I've ripped out the carpet worst affected by fleas. We had originally planned to do things room by room as time and money allowed. But due to the fleas and moths that might need rethinking, and we might just have to bite the bullet and rip out all the existing wool carpets.

 

[Kearn]

Do you mean you only sorted the carpet moth problem out by getting rid of the wool carpets then?

Yes. There may have been some other sprays or powders we didn't try, but they were stubborn buggers! The carpet was only down 6 years, one of the many stupid PO choices. We had moths in various rooms and huge bald patches of clearly tasty carpet ! It was always on the to do list, there's no place for carpet in our house, so we're glad to see the back of it and the gorgeous now restored wide Georgian pitch pine boards... Amongst other era wood.

 

[Lime]

................................Why buy a period house and then try to make it like a modern one?

I agree.
The idea of using modern controls is fine as long as the heating system is able to produce enough heat.
IME most old houses take a colossal amount of heating and it is best to settle for a background heat and only have a few hot spots that can be described as warm.
Zoning the house and only heating one or two rooms will emphasise how cold the rest of the house is and make most of the house uninhabitable in winter.
Further, it will take days for a cold room to warm up properly and economics will start to bite when the bills come in.

With regard to fleas, spraying affected areas with dilute Dettol works quite well.

 

[skier-hughes]

IME most old houses take a colossal amount of heating and it is best to settle for a background heat and only have a few hot spots that can be described as warm.
Zoning the house and only heating one or two rooms will emphasise how cold the rest of the house is and make most of the house uninhabitable in winter.
Further, it will take days for a cold room to warm up properly and economics will start to bite when the bills come in.

Modern day zoning means rooms not used regularly can be kept warm and rooms used the most hot, so that you don't have uninhabitable rooms and heating bills are kept to a minimum.

 

[stuartlowb]

This is exactly what I do. We have 5 zones set up with the Honeywell Evohome system which works brilliantly and has saved me a fortune in heating oil. We have had our system for 3 years now and are very happy with its flexibility. There are other and maybe better systems out there now but in my opinion, zoning is an excellent solution for a large home.

 

[fernicarry]

Zoning doesn't mean not heating parts of the house, it means choosing a temperature appropriate for how the zone is being used. We don't let any room completely cool down because that's inviting condensation problems. The warmer you try to make each zone, the faster you lose heat (first? law of thermodynamics) so the cost goes up exponentially. It really doesn't make financial or environmental sense to fully heat spaces you don't intend using but at the same time the fabric of the building needs a certain amount of heat in it at all times.

 

[Lime]

Zoning can mean anything you like.
There is nothing new in partially heating a room or zone either.
My point was that no matter how sophisticated a system you have it can still be very expensive to heat an old home to modern standards.
Why buy a period house and then try to make it like a modern one?

 

[ElectronicFur]

Zoning can mean anything you like.
There is nothing new in partially heating a room or zone either.
My point was that no matter how sophisticated a system you have it can still be very expensive to heat an old home to modern standards.
Why buy a period house and then try to make it like a modern one?

Because heating a period house as economically as possible whilst taking the historic fabric of the house into account makes sense...

 

[skier-hughes]

Why buy a period house and then try to make it like a modern one?

When my house was built it had heating, I'm just using a modern way of doing it which works in the house, doesn't ruin any of it's antiquities and makes my life more enjoyable.

 

[Flyfisher]

Why buy a period house and then try to make it like a modern one?

Because no one in their right mind wants to live in conditions prevailing hundreds of years ago?

But you raise an interesting question - what is it that we like about period properties? Is it really just because they are old and have 'character', however that might be defined?