Central Heating - Multiple Zones?

[Dibs-h]

I've read posts here of folk separating the heating at home into 2 (or more) zones. Say 1 for the rads upstairs and another for the downstairs. I can see the logic for this - why heat half the house when it's empty, etc. and given that our annual gas consumption is somewhat eye watering - I'm been meaning to look into this for a while.

Whilst surfing the web - looking at programmable room stats, wired vs wireless, etc., I came across the following article,

http://www.telegraph.co.uk/property/pro ... decay.html

which made me pause, especially the following paragraph,

As with many energy-saving ideas, this one has been promoted by the Government in response to current “climate change” hysteria, without regard to the bigger picture. Repairing condensation-damaged decorations will consume far more money and energy than that saved by reduced fuel bills. In my opinion, it would better for your wallet and the environment for you to keep the whole house heated and therefore above dewpoint temperature.

Any thoughts\advice? I have come across similar mentions before.

Until this point - I was erring down the road of a 2 wireless programmable room stats and a pair of 2 port valves (or possibly getting away with a single 3 port valve that does mid-position). With the upstairs bathroom rad as the the bypass (i.e. on all the) as the bathroom is on the other side of the wall where the 22mm heating pipes drop down.

Cheers

Dibs

 

[sparkymarky]

i would ignore jeff howells article, it`s all well and good writing a article which is his own opinion, but the article doesn`t take into consideration the different types of houses cob, concrete block, cavity wall insulation, vents above windows, double glazing ect ect... similar single minded articles were written stating that lower sulphur heating oil would cause aga`s and rayburns to go wrong, which is a load of rubbish there was alot more variable factors.

i would defiantly consider a two zone system for upstairs and downstairs (most new houses are these days anyway with underfloor heating) however i wold forget about programmable room thermostats just use a normal wireless room stat ideally a honeywell (like this one http://www.ebay.co.uk/sch/i.html?_from= ... Categories its very reliable and doesn`t require linking to the base unit) then use a dual channel programmer to control the zones.

i would stay away from y plan zone vales, fit individual zone valves when they go wrong it will be easier and cheaper to repair them, the wirings is also easier to configure.

go for a auto bypass don`t use a radiator they only cost around £15 and they limit central heating throttle noise through radiators as the trv`s close down.

if you need any advice on wiring of plumbing configurations just ask.

hope this helps.

cheers, mark.

 

[Dibs-h]

i would ignore jeff howells article, it`s all well and good writing a article which is his own opinion, but the article doesn`t take into consideration the different types of houses cob, concrete block, cavity wall insulation, vents above windows, double glazing ect ect... similar single minded articles were written stating that lower sulphur heating oil would cause aga`s and rayburns to go wrong, which is a load of rubbish there was alot more variable factors.

i would defiantly consider a two zone system for upstairs and downstairs (most new houses are these days anyway with underfloor heating) however i wold forget about programmable room thermostats just use a normal wireless room stat ideally a honeywell (like this one http://www.ebay.co.uk/sch/i.html?_from= ... Categories its very reliable and doesn`t require linking to the base unit) then use a dual channel programmer to control the zones.

i would stay away from y plan zone vales, fit individual zone valves when they go wrong it will be easier and cheaper to repair them, the wirings is also easier to configure.

go for a auto bypass don`t use a radiator they only cost around £15 and they limit central heating throttle noise through radiators as the trv`s close down.

if you need any advice on wiring of plumbing configurations just ask.

hope this helps.

cheers, mark.

Mark

Cheers for the advice. After posting, I spoke tomy tame'ish heating chap and he suggested to not be tight and fit a pair of 2 port valves for exactly the same reasons you stated.

I had thought about 2 wireless room stats as one could have the downstairs one in the room in which we are in, but having come across the advice that the room in which the wireless stat is in, not to have TRV, so wondered how you could take it from room to room. During our discussion it was realised that doing this could end up with more problems than it solves.

In the end going to go for a wired stat (non program) upstairs, as it's dead easy to run the cable to the boiler in the loft and a plain wireless one on the ground floor (to save the wireless headache & again a non-prgram one).

Cheers for the auto Bypass advice. We kind of want the upstairs bathroom on, irrespective of whether the downstairs rads are on, upstairs are on or both. Does that mean fitting a bypass valve as well?

Cheers

Dibs

 

[RogerS]

Dibs..my first reaction when I read the DT article was 'cock'. Sparkymarky puts it much better than me. I'd definitely go down that route...the downside is going to be how easy is it for you to split the pipes into two zones? You might also like to consider one of these http://www.totalenergycontrols.co.uk/p/ ... master.php

Last winter we pulled the house temperature right down and use a wireless thermostat in the sitting room while we're there in the evening. Gives just enough background heating to the rest of the house while the heating system is feeding the sitting room. I've got a legacy thermostat/timer upstairs and use that to fire up a bit of heat into the house first thing in the morning. Any localised heat we need in a room that's not used very much is provided by a quick burst of electric fan heater. With ch oil at over 55p a litre currently, i can see extra sweaters. The open fire in the sitting room also keeps the house warm burning offcuts from the workshop.

Check out one of these to see where you are losing heat. http://www.youtube.com/watch?v=xpifuiVpv2w

Roger

 

[Lons]

I don't see the point Dibbs. We have TRVs on every rad (15 of them) except the en-suite towel rad and just adjust them as necessary. You have to keep the bedroom doors shut whatever you do so for the sake of a few seconds it works for us.
Whoever is up first turns it down and in the evening, wife goes and brushes teeth, dressing gown on etc about an hour before retiring so she re-adjusts the trvs - voila

Just my opinion and there are only 2 of us in the house which makes it easier but I'm a tight git, we don't have gas so heating is oil (ouch) and our bills are within reason in the current climate.

Bob

 

[Digit]

That DT comment is rubbish, fine, keep above Dew point, I agree, but he infers that that can only be acheived with unoccupied room temps at the same comfort level as occupied rooms.

Roy.

 

[wobblycogs]

At last a chance to repay some of that great advice you've given me over the last couple of years, Dibs.

We've mostly fitted, and by that I mean we've actually done all the plumbing and wiring, a 13 zone heating system built around these programmable room thermostats from John Guest: http://www.speedfitufh.co.uk/network-programmable-room-stat.php. The system is fitted in a detached 6 bedroom Georgian town house which leaks heat like a sieve. For the most part every room is on it's own thermostat and can therefore be controlled individually.

So, why did we do it? When we bought the house there were only two of us (so we wouldn't be using all the house) and I work from home full time. Both of those factors said to us that what we really wanted was a way to heat just a portion of the house and at different times of the day. In the week I want just the office warm all day and in the evenings we wanted just the living room and bedroom warmed. We also wanted to optionally heat other rooms on demand.

Last winter was the first year we've lived with the system and, of course, it was one of the coldest on record. I'm really pleased to say that it worked better than I could possibly have dreamt. Our heating bill was comparable to my parents 10 year old, insulated up to the eye balls, house which has a standard heat everywhere system fitted. Better than that though we were able to just dial up the temperature in a room when we wanted much like you would turn on the light. I rattled out some calculations based on how much energy I think we would have used to get the same result but using a standard whole house heating installation and the system will easily pay for itself this winter.

Down sides? You'll probably have to fit it yourself as finding a plumber that knows about it is basically impossible. When we put in ours the only thermostats available were wired which means a lot of cable runs, I think you can get wireless now though. If it's very cold outside it can take a while for an unheated room to warm up so a bit of planning ahead may be necessary - was never a problem for us though.

Some things to think about if you go for a system like this... massively over side your radiators for each room, at least 1.5* what the regular calculations recommend. This is because the rooms around you will probably be cold, if they aren't cold the thermostat will fix the over heating anyway. The manifold is chunky and needs a surprising amount of space around it, we screwed up and had to fit it sideways which looks awful but it works.

Would I do it again? For a house like this which is difficult to heat, most definitely. For a modern, well insulated house: no, I'd fit a two zone system.

Oh, as for condensation we just set all the stats in unused rooms to 11 deg C and leave it at that.

 

[sparkymarky]

but having come across the advice that the room in which the wireless stat is in, not to have TRV

just take the head off the trv`s or turn the trv up to max then the wireless stat would shut the heating off to perform `boiler interlock`before the trv shut the radiator off. the maximum setting for most trv`s is 28-33 0c air temperature so if your wireless stat is set at 21 0c then it would shut down the heating in the room you are in.

the advice you have been given is in regards for new buildings, the reason is to show that the heating has interlock and therefore efficient, on existing houses unless you want to sell the house you can do what you like as long as the system suits you and it saves you money.

We kind of want the upstairs bathroom on, irrespective of whether the downstairs rads are on, upstairs are on or both

why not stick in another zone for the towel rails you can run the towel rails as bypass`s, i would still recommend for the cost of the auto bypass to install one even if you keep the towel rails on.

 

[johnf]

Cut your bills by 60 to 70% put in a ground source heat pump heat the whole building 24 hrs of the day works for us 3000 ft2 of property

Electricity bill for the year looks like £1000 max thats for everything heating hot water cooking lighting .

Then put in solar panels make your own power and the FIT pays the power bill for the next 25 years job done
By the way the ground source heat pump will also pay the RHI subsidy from October 2012

 

[Mark A]

we just use the TVR's to adjust the temperature. Still cost over a grand in oil last winter though (stone house :duno: )

 

[Dibs-h]

Cheers Chaps for the advice.

Mark - my "tame" heating suggested exactly the same, i.e. take the TRV head off the rad that has the wireless stat in that room. So will be going for that. Will have a chat with my "tame" heating chap about the bypass and\or bathroom circuit. Thankfully he's quite familiar with the piping in our house and cutting the flow to achieve the 2 circuits should be very straightforward (I hope).

Wobbly\Roy - the longer term aim is to fit UFH heating throughout the house fed (primarily) by 2 evacuated tube panels on the workshop\garage room (which is South facing) feeding a thermal store. That will have a large manifold, with something like 10 zones, with each room\zone having it's own programmable room stat. Knowing my luck and work list it might be a couple of years before that happens, so want to cut our current gas bill, which is around 1.5K. I figure that at a cost of no more than £150, I could split the zones and save that cost in the gas bill before the UFH comes in.

Also looking at fitting insulated plasterboard with 2" kingspan on all the exterior walls - this will probably happen in the next 12 months, room\wall at a time - as I am sick of the gas bill. Will mean replacing the original coving on those walls, but as I'm already replicating the coving, as it's missing in a few rooms - no real headache to make up some more (already have the running moulds).

Thanks

Dibs

 

[9fingers]

When I put our central heating in around 1984, I put in two zones. Essentially upstairs and downstairs but the upstairs bathroom was plumbed in to the downstairs circuit with a then rare thermostatic valve and an oversized radiator.
The idea being that there would be scope for convection to the upstairs bathroom when the pump was off due to no demand downstairs.

We have never even switched on the upstairs circuit so in practice there is no need for upstairs heating - apart from the bathroom. Sufficient warm air goes up stairs from the hall.

So maybe it is worth considering what heating requirements you have - I could have saved a lot of time and effort on my installation.

Bob

 

[wobblycogs]

Are you planning on fitting UFH to existing wooden floors?

We took a good long look into ways of doing it and everyone said just don't bother it's more work that it's worth and that included the guys setting the stuff. Every single person we spoke to said that unless you were totally stripping the house back down to joists and brick work it just wasn't worth the effort of trying to fit the pipe work and insulation required.

 

[9fingers]

UFH can be very effective for use with the low grade heat (low temperature) from heat pumps. So yes it does involve a lot of upheaval but with the future incentive schemes that John F mentioned UFH might be appropriate.

Bob

 

[Dibs-h]

Are you planning on fitting UFH to existing wooden floors?

We took a good long look into ways of doing it and everyone said just don't bother it's more work that it's worth and that included the guys setting the stuff. Every single person we spoke to said that unless you were totally stripping the house back down to joists and brick work it just wasn't worth the effort of trying to fit the pipe work and insulation required.

Yes - going to fit it to upstairs wooden floors. Most of the floors will come up as they've butchered over the years. The plan is to fit mahogany parquet (which is sitting in the workshop) on the ground floor, which will mean lifting the floorboards which are in very good condition. These will go upstairs - so if I'm replacing the upstairs floorboards, might as well put the UFH heating down and 2" kingspan to reduce heat losses. The loft hasn't any flooring down - so it's very straightforward to lay it down there.

Not paying labour - allows such follies to be entertained, especially if I have a oversized solar setup. :mrgreen:

Dibs

 

[Lons]

, so want to cut our current gas bill, which is around 1.5K. Dibs

That seems very high to me Dibs so you clearly need to do something. How old is your boiler / rads?

We have a pretty large house, quite exposed and the winds are bloody cold in Northumberland but our combined oil and electricity bills are a lot less than that.

Bob

 

[Dibs-h]

, so want to cut our current gas bill, which is around 1.5K. Dibs

That seems very high to me Dibs so you clearly need to do something. How old is your boiler / rads?

We have a pretty large house, quite exposed and the winds are bloody cold in Northumberland but our combined oil and electricity bills are a lot less than that.

Bob

Hi Bob

The boiler is a condensing combi about 2 yrs old but the rads are on the whole quite old - at least 15 yrs old. A few I've replaced in the last 2yrs, as 1 rotted thru the one in the living room, was blatantly undersized. Don't want to replace the rest as they heat those rooms fine and with the UFH in a few yrs time - they won't be in long enough to get the payback.

The main problem is that the heating is on 24/7 (or has been over the last 10yrs), even when the house is unoccupied, let alone all of it when the house is occupied.

No room stat as well. So splitting the zones and using 2 room stats should (I hope) make a noticeable difference.

The cause of it is (as is usually the case) - SWIMBO! When we got married yrs ago, gas was alot cheaper so leaving it on all the time - 'cos she preferred it that way, was fine. But with the current prices - obviously not. So thought of the current plan - before we try the "wear a thick jumper\fleece etc. love!"

And as you know - Plan B isn't going to go down well.

Dibs

 

[Lons]

All makes sense Dibs - cheaper to get a new wife? :roll:

I've got the opposite in that wifie is hot one mitute and cold the next whilst I like a constant comfortable temp though our room thermostat is never above 18 deg.
I think I'm kept warm by the gallons of coffee I drink :wink:

I've changed a number of our rads and was astonished at how much hotter they are and much quicker to heat up . Old ones are about 30 years now.

Bob

 

[RogerS]

And if anyone is thinking about creating a system like this, do NOT use plastic pipe unless you have one of those gizmo's in the circuit to extract the magnetite out of the water. Otherwise you will find that if you have some circuits that are rarely used...and so have little or zero flow through them...then they will be blocked by magnetite which seems to prefer settling in a plastic pipe compared to copper. DAMHIKT

 

[RogerM]

Another fan of dual zone CH here. As I think I've mentioned before, we split upstairs from downstairs, and control the zones with a 3 zone (Up/Down/HW) Horstmann ChannelPlus H37XL series 2 three channel programmer. We were warned off prorammable thermostats by our plumber, and just use 2 wireless Drayton Digistat RF1 thermostats to control each zone. The downstairs one follows us into the lounge in the evening. We just need to ensure that the TRV is turned up, and if the log burner is on the CH turns off downstairs completely. As we don't use the lounge during the day, we turn the TRV right down before we go to bed so that it doesn't come on in the morning. The benefit all gets negated of course if SWMBO goes in to the lounge too draw back the curtains in the morning and leaves the door wide open! #-o

We keep the TRVs in the spare bedrooms on very low, and have never had any problems with condensation. It is important though to keep the doors upstairs closed during the day and early evening.