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B

Boatist

Hello all.

We are currently building an extension on our house and will have a 4 bedroom house when it's all done. We've never had central heating, so as part of the project we're putting a brand new heating system in the whole house. We want to do as much of the work ourselves as we can, but could really use some advice...

I have attached a drawing of what I've dreamt up and would really appreciate some comments. We had this (maybe mad) idea of having 8 heating zones in the house, with programmable room stats in most rooms, and some smaller radiators on TRV's. Different parts of the house get used through the morning, day and evening so multiple zones would work well for us. I've done bits of plumbing before and electrics are easy for me, but there's a ton I don't know here!

Will the pump in a combi boiler cope with this system? Can I really do that with the return pipework!? Will the extra pipe losses make the whole thing pointless? :crazy:

Thanks so much for your help!

I hope this attachment works...
View attachment central-heating.pdf
 
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Sounds a little OTT, Loads of expensive materials and complicated for small gain. Have a look at zoning each floor with TRV's on each radiator. I am not saying it won't work, just look at the gains against the work involved and operation for the user, with all those programmable room stats.
 
Thanks for the comments! I hadn't heard of the HR20's. If they work well then that would be a huge saving on the system. It looks like there's no way to tell the boiler when to fire if there's simply one HR20 on every radiator though. And the smaller radiators (en-suite etc) will need valves also. I'll spend some time delving deeper into that honeywell brochure!

The common return looked questionable to me too... Anything to save pipe.
 
Read the Honeywell link Mike posted. That will tell you how to control it and what additional parts you need.

If you commoned your return on the way you have drawn the system your rads will back heat.
 
Hope your stayin in the property for a few years would any one like to work out the payback time, i had a guy last week wanting to change his open vented system working great to an unvented with each room zoned, OMG he was planning in selling in 5 years he would never get his dosh back or would the buyers pay more because each room was zoned ? worth thinking about, same goes for solar pannels, one other point with regards to zoning you tend to get cold rooms and warm rooms i still believe in keeping the fabrication of the house warm during the winter months boiler then just ticks along. what do you guys think
 
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Thanks Tamz, that's good to know... haha yes we'll be here for a while yet. Not expecting it to pay back really, just be as efficient as it can while still being comfortable to live in.

I'm having trouble finding radiator manifold systems. I've seen the "speedfit energy saver plus", but I guess you need to contact them direct to design it for you? Obviously simple manifolds are easy to find, but something with actuators that's for Rads and not UFH?
 
instead of wasting money on 8 zones? why not put in solar panels and a thermal store to be a bit greener and then you might gain something that you will appreciate in the long term. A warm house for lots of money saved, get some expert advice in and youll benefit in the long term.
 
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Not much solar activity here in Yorkshire 🙁 that's why we're so miserable... Good point about thinking of a better way to spend all that money though.
 
lol. That's almost exactly what we've got now Vern. I should just leave it alone right?
Lol I do a lot of this stuff.......

scrap the combi.....you need a system boiler with an unvented cylinder, assuming house not bungalow, 3 zones being downstairs, upstairs, hot water, TRV's on all rads except where programmable stats etc add 4 th zone for UFH manifold if required.....
remember a combi cannot produce ANY heat to any zones whilst hot water is being drawn off....think off all the baths, showers, sinks and occupants too, also that many combi's have an anti cycle delay so won't return to heating straight away after a sentinel point has been used!
 
Honestly, if you're starting from scratch, go with a system boiler, unvented cylinder (twin coil to add solar later if desired), heating installed on a manifold. Possibly have underfloor heating downstairs if your house is sufficiently insulated.
 
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Honestly, if you're starting from scratch, go with a system boiler, unvented cylinder (twin coil to add solar later if desired), heating installed on a manifold. Possibly have underfloor heating downstairs if your house is sufficiently insulated.
Agree on the twin coil, can be piped for rapid heat up (recovery)via boiler, or add panels later if your feeling green
 
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Agree on the twin coil, can be piped for rapid heat up (recovery)via boiler, or add panels later if your feeling green

Twin coil unvented system with a few panels you will save about 400 quid a year on ya hot water just think in 10 years you will have just about broke even ! And with the good weather we are havin ?
 
Interesting that you wouldn't consider a combi. I gave it quite a bit of thought, as a system boiler does seem better for a house of this size, but I'll tell you why I decided combi...

There's an electric shower in the bathroom that does the majority of the work. We use the bath, but it can go for days without being used sometimes, and we use a dishwasher for almost all washing up (seriously, whatever we can cram in there!). Also we have a wood burning stove in the lounge, will likely put one in the dining room, and it's looking like an aga in the kitchen, so lots of background heat downstairs.

So, water could be sat wasted in a cylinder, and i'm not too worried about some heating interruptions (although if these can be quite long then it needs thinking about). Do you think combi is an ok idea now you've got more info?

p.s. you're all gradually chilling me out on the zoning idea 🙂
 
Hello all.

We are currently building an extension on our house and will have a 4 bedroom house when it's all done. We've never had central heating, so as part of the project we're putting a brand new heating system in the whole house. We want to do as much of the work ourselves as we can, but could really use some advice...

I have attached a drawing of what I've dreamt up and would really appreciate some comments. We had this (maybe mad) idea of having 8 heating zones in the house, with programmable room stats in most rooms, and some smaller radiators on TRV's. Different parts of the house get used through the morning, day and evening so multiple zones would work well for us. I've done bits of plumbing before and electrics are easy for me, but there's a ton I don't know here!

Will the pump in a combi boiler cope with this system? Can I really do that with the return pipework!? Will the extra pipe losses make the whole thing pointless? :crazy:

Thanks so much for your help!



I hope this attachment works...
View attachment 12953

There are so many good products out on the market for controlling every radiator in the house, Syxthsense make a electronic radiator valve, B&Q do one made by Terrier, Honeywell too make one some are wireless operated for a single programmable controller ,the World is your Oyster. Good luck with the project, make sure the boiler has an automatic bypass with all these rads shutting down the hydraulic will change in the system and the water flow through the boiler must not drop, hope this helps
 
Interesting that you wouldn't consider a combi. I gave it quite a bit of thought, as a system boiler does seem better for a house of this size, but I'll tell you why I decided combi...

There's an electric shower in the bathroom that does the majority of the work. We use the bath, but it can go for days without being used sometimes, and we use a dishwasher for almost all washing up (seriously, whatever we can cram in there!). Also we have a wood burning stove in the lounge, will likely put one in the dining room, and it's looking like an aga in the kitchen, so lots of background heat downstairs.

So, water could be sat wasted in a cylinder, and i'm not too worried about some heating interruptions (although if these can be quite long then it needs thinking about). Do you think combi is an ok idea now you've got more info?

p.s. you're all gradually chilling me out on the zoning idea 🙂

It maybe possible with the combi, with all back up heat and electric shower, depends on number of bods in the house and bath usage etc.....
 
Personally if I was having a new heating system fitted with pressurised HW I'd be getting rid of the electric shower.

Combi would save you lots of money on install cost
 
Me too would not be seen dead under an electric shower , maybe if it wasn't bonded properly.

They are only fit for Hotels, its a no-brainer :wink_smile:
 
Interesting that you wouldn't consider a combi. I gave it quite a bit of thought, as a system boiler does seem better for a house of this size, but I'll tell you why I decided combi...

There's an electric shower in the bathroom that does the majority of the work. We use the bath, but it can go for days without being used sometimes, and we use a dishwasher for almost all washing up (seriously, whatever we can cram in there!). Also we have a wood burning stove in the lounge, will likely put one in the dining room, and it's looking like an aga in the kitchen, so lots of background heat downstairs.

So, water could be sat wasted in a cylinder, and i'm not too worried about some heating interruptions (although if these can be quite long then it needs thinking about). Do you think combi is an ok idea now you've got more info?

p.s. you're all gradually chilling me out on the zoning idea 🙂

Well the aga can heat the water so there be plenty of hot water
Once you have unvented hot water you won't use an electric shower
No point putting in an electric aga waste of time and money
And as for zoning you will regret not doing it
You can get a manifold standard zone manager few actuator heads and a few stats some mlc or pex it won't break the bank
And even if your thinking of selling in future it is a selling point as people do want control nowadays and if you like gadgets you could go for a climote controller
 
haha, electric showers only fit for hotels! I like it. They pay for themselves when the boiler goes down though :cool4: Our problem, if you can call it a problem, is that we've lived with an electric shower and storage heaters for 10 years now. We have no idea what we're missing out on!

We actually have a hot water cylinder which is only about 5 years old currently heated by an old oil aga (which is going), so if we could use this cylinder then a system boiler is really worth thinking about. It doesn't have a cylinder stat or anything? The new aga will be gas and not considering using it for hot water. We've always needed to put the immersion on if we want it hot enough for anything. No good really.

When you say use a manifold and a few actuator heads, are you talking about the UFH electrothermic actuators? Are they suitable for radiators? Would the whole manifold need a zone valve to isolate it when not calling for heat?
 
haha, electric showers only fit for hotels! I like it. They pay for themselves when the boiler goes down though :cool4: Our problem, if you can call it a problem, is that we've lived with an electric shower and storage heaters for 10 years now. We have no idea what we're missing out on!

We actually have a hot water cylinder which is only about 5 years old currently heated by an old oil aga (which is going), so if we could use this cylinder then a system boiler is really worth thinking about. It doesn't have a cylinder stat or anything? The new aga will be gas and not considering using it for hot water. We've always needed to put the immersion on if we want it hot enough for anything. No good really.

When you say use a manifold and a few actuator heads, are you talking about the UFH electrothermic actuators? Are they suitable for radiators? Would the whole manifold need a zone valve to isolate it when not calling for heat?

Yes underfloor actuators are for either underfloor or rads its only opening and closing a circuit no need for zone valves if you got a spark will wire it simply
 
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All the heating engineers have given excellent advise
I am not an engineer and can't comment on any of the technical queries.
OMG you don't have gas central heating!

You might find these two articles helpful, disadvantages of Combi boiler:
The Disadvantages of a Central Heating System With a Combi Boiler | Suite101
Pros of combi boiler:
Combi Boilers & the Benefits of a Hot Water on Demand Boiler | Suite101
I can vouch for them - I wrote them.

If your hot water is going to be supplied by the aga or wood burner then a combi should be good for you.
We are a family with 3 children and very happy with our combi boiler - My heating engineer husband still says a system boiler would be better if we had the space.
Saving space is one of the many advantages to combi boiler.

But if the boiler is going to supply your hot water you will find it is excellent for a shower but takes ages to fill the bath - you don't want it if you are bathing once a week or more.

Good to plan what you want and fine to do much of your own installation work but

I STRONGLY RECOMMEND - you sign up your gas installer BEFORE you buy or do any work.
I can't tell you how many times people start DIY work only to find it is wrong in some way and ends up being more expensive to put right - it is a lot.
By all means plan it in detail, draw it, choice the exact products but then go through it all with the gas installers. They may spot problems or give you other good suggestions.

My last tip - Do not supply your own boiler - you will not save money buying it on line instead of letting the heating engineer arrange it.
 
Thanks Tara! lots of good advice there.

I'll give some serious consideration to a system boiler. Its just the expense of the unvented cylinder that puts me off, plus I couldn't install the tank myself. But I'm sure it would be a better job in the end. There might be a possibility of getting a tank in the roof space, will need to ask the architect about that.

As for central heating my favourite idea is radiators on a manifold. There is potentially a great location for it right in the middle of the house.

There's such a lot to think about it hurts my head. Better to do the thinking now though I suppose... Thanks for all of this help!
 
If you have all these different heat sources, stoves aga's and another stove planned a thermal store linking all your heat sources plus a system boiler may be the best idea to link all the sources. You could get your new stove with a boiler attached and generate more "free" heat while you are burning it.

I agree with Mrs Tara. You really should get a good installer on board and go through this discussing your options as there are so many and keeping you right.
 
😱 even more to think about! Just when I thought it was ok to go back in the water, haha. That's interesting actually Tamz. We were looking at biomass a while back and they use that kind of system. Might be a bit more complexity than we can budget for though, but we'll see.

I'm going to crawl into a hole for a few days and let all of this digest. Best to let the decisions make themselves... Thanks again :rockon:
 
having reread your op, forget aga and boiler and bung in a rayburn 480 or bigger, built in boiler and separate cooker section , much more efficient than an AGA, cheaper to run than your other optins, unvented cyl available on it as well, and keeps house nice and warm at same time. cheaper to install than aga/boiler combination
 
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