Not putting the heating on - how's it going...?

One point possibly worth mentioning on flow temps is legionella. I’ve no idea on the real risk of legionella but it is something that comes up when lowering flow temps , particularly if you have an indirect hot water cylinder.

The point on experts is one that irks me a lot. So far I’ve not met a heating engineer who doesn’t wang the flow up to 70. Similarly when recently having windows installed- being told that the fitters have “been doing it for 20 years” and so “know what they’re doing”- Problem is they’ve been doing it wrong for years. The other problem is there are so many variables and no arbiter even if you had a new heating install, you won’t have any come back if they’ve set it up to run inefficiently at 70.

There's a heat geek article about legionella.

Call me old-fashioned but I would stick with people who do this stuff for a living – aka ‘experts’.

The problem with people who do this for a living is that they don't need to be a tual experts they just need to know a bit more than the people whose heating they are working on.

Qualified plumbers fitted my pump backwards, left the flow temp on max, didn't bother balancing the system, fitted the stat too close to the rad, over-specced the system, fitted a shit boiler, and later didn't open up the boiler to clean out the condensate and subsequently discover a problem.

I wouldn't mind paying someone to look at this stuff if I could be sure they knew what they were doing. The guy I got in to service the boiler didn't even bother coming to his followup appointment or even respond to his messages.

The concept behind heat geek seems to be to sell services from people who actually understand the engineering behind how to set up heating properly. And not every plumber does. There are several examples on this thread.

So yeah with my Physics degree, my professional diagnostic skills, my DIY experience and the internet I'll have a look at it myself and tune what I can. I know enough to know when to stop. I'm not touching the burner or the gas side for example.

That said, possibly the biggest difference between a plumber and me is that I live here, so I can spend as long as I want fine tuning this particular house and learning how things respond. A hired plumber can't do this.

Mines a Worcester Greenstar combi so no tank, just showered at 45c no mixing, still felt a touch hot for me.

There's only me using it luckily

Mines a Worcester Greenstar combi so no tank, just showered at 45c no mixing, still felt a touch hot for me.

There’s only me using it luckily

Yeah mines a pretty new Baxi combi - i still blend a tiny slight touch of cold in, HW set at 40c as thats as low as it will go.
Less steam too so better for the bathroom humnidity/dampness.

Equally, wallking around my neighbourhood the other day having a nose at peoples flues – the number of houses with huge plumes of steam errupting from them was staggering.

Silly question perhaps, but what does this mean please? I see a good blast of steam emit from my flue when the boiler fires up - is this not right?

I have both dials (rads flow temp and hw) set to 12 o clock, which I suspect is 55c ish?

I've run a mini-experiment over the last couple of days where we've had reasonably comparable outside temperatures.
I haven't changed any of the TRV settings - all set to #3.
There is no separate thermostat to control boiler at all. (Usually runs off the timer.) 6 year old Baxi platinum 28.
Xmas day - had boiler set to '48' and ran it for 8 hours 10-6pm. Temp stable at 18ish degrees (+3 showers on HW from boiler - no tank).
Yesterday - had boiler set at '65' (as per Baxi booklet) and ran for 2 hours in the morning 9-11. Temp achieved was 19.4 degrees and dropped to 15.7. CH back on for 2 hours later 5-7pm (+2 showers on HW from the boiler).
Gas cost yesterday was £1-ish more than Xmas day's total.
No idea what this means, other than it seems cheaper to have the boiler on for longer at lower requested temp than shorter for higher requested temp. Now thinking a thermostat of some variety might be the answer, though, given our CH is generally not in use April thru October, the cost of the stat plus person to fit it all probably is more than the saving. I've rambled enough now, and confused myself further. I reckon I'll save an absolute bloody fortune if I just stop thinking altogether!
🤔😂😂😂😂

Silly question perhaps, but what does this mean please? I see a good blast of steam emit from my flue when the boiler fires up – is this not right?

Yeah you will see some steam, but some of my neighbours look like a constant volcanic eruption on one of Jupiters moons, sugesting they've not done any optimisation of the boiler.

Silly question perhaps, but what does this mean please?

There is water vapour in the natural gas along with methane and whatever else, o when you burn it one of the byproducts is H2O which on a cold day condenses into the steam you see. Your boiler is designed to condense some of that steam inside it whch recovers more heat fro the gas. The better the set up, the more steam is condensed and the less you will see coming out. But also, the less gas being burned, the less steam there is to begin with.

So a system to hat hasn't been set up well will produce a lot of steam because it's not condensing, and not running efficiency either. The above poster has a boiler that can run super low which is both not burning much gas and also condensing very well. But it is probably burning for much longer. The efficiency savings for setting up the flow temps and rate correctly are probably 20%, from best case to worst, I'd say.

That's impressive that my oil boiler gets water vapour out of the gas .

Why are you burning oil at all trail_rat? Surely the hot air coming out of your mouth is enough to heat your home?

That’s impressive that my oil boiler gets water vapour out of the gas .

H2O is a product of combustion, irrespective of the source.

Call me old-fashioned but I would stick with people who do this stuff for a living – aka ‘experts’.

But how do you know they are?

I went through 6 local 'heating engineers' before I found one that actually knew more than just how to bang a new box on the wall and connect the pipes.

Most of these people know what they know, but dont know why it has to be done a certain way.

I'm fortunate as a former Domestic energy assessor, it was pretty easy for me to put out some of the lingo and see how they responded.

We gave in during the cold spell.
-8 during the day.

£239.00 for the last month, central heating on for less than 10 days.

Gt absolute f.

We need to embrace our inner children and get used to ice on the inside of the windows. We've gone soft.

H2O is a product of combustion, irrespective of the source.

Correct. But my (tongue in cheek) point still stands.

My comment was really for the benefit of others...😉

But my (tongue in cheek) point still stands.

Your point was that you don't have gas? But the person I was addressing does.

Not putting the heating on is going rather well seeing as it's been broken since the 19th and isn't going to be fixed until Jan 5th. I'll never take heating and warm water for granted ever again. Properly fed up with being cold all the time in the house especially over Christmas. ☹️

We can fix it remotely.
Tell us what's going on, or isn't.
Have it fired up in no time.
Or possibly wait for a plumber to come out and scratch his arris and tell you itsca 3 dayv wait for a new pcb from the merchant and it will be £205 plus fitting, plus vat.

What’s the best additional insulation to add to the hot water tank? I see there are loads of covers available which wrap around the tank, but they can’t all be the same?

Is your tank not pre-insulated?

So a system to hat hasn’t been set up well will produce a lot of steam because it’s not condensing, and not running efficiency either.

Thanks Molgrips. So is inefficiency something that can be identified/calculated by simply seeing a lot of steam (which was how I took the initial comment I responded to)? I ask as I've previously read up on the flow temp advice and have dialled mine back to (I think) 55c, but still occasionally notice the boiler bellow out steam. I assumed this is correct operation, but now wondering whether I should be seeing less steam, and whether it's currently a sign that I should be turning the flow temp down further. I guess it's a case of finding the balance by trial and error - turning the flow temp down as far as you can until the house is struggling to heat. But the flue will always kick out steam regardless?

As mentioned elsewhere in the thread, there's a need to know things are running as efficiently as your system can, rather than just working to kick out heat.

The tank is pre insulated, but I do believe it would benefit from some further insulation as the insulation feels warm to touch.

So is inefficiency something that can be identified/calculated by simply seeing a lot of steam

No. There will likely always be steam. In theory with a low enough return temp you could get rid of much of it, but you probably won't be able to run your system that low for other reasons.

There will always be an amount of steam, but the quantity can be used as a proxy for whether your boiler is condensing well or not.

When mine is running the heating, theres the faintest of wisps that dissipates almost immediately, and when its heating the cylinder, it runs at full bore and chucks out noticeably more. (Hot water priority setup and a system boiler)

Pretty much it tells you nothing else about the system though.

£239.00 for the last month, central heating on for less than 10 days.

Sounds like you need some insulation. Ours was set to 18-20 degC all day every day and only hit £175 (ouch) on octopus variable tarif. That's a rental 1930 ish 3 bed semi. YMMV if you aren't on a gas supply / much bigger house etc

My supplier asked me to increase my direct debit several months ago, to allow for energy price increases, so I upped it to slightly above what they asked for, £170/month. I’ve got the system set at 17°/12°/15°/12°/16.5°/14°, highest first thing in the morning, lunchtime and evening. Just checked my latest bill, and I’m £196 in credit…

There will always be an amount of steam, but the quantity can be used as a proxy for whether your boiler is condensing well or not.

Only if you are comparing similar volumes of gas being burned. A bigger boiler.hewting a larger house more efficiently would produce more steam than a small one running less efficiently.

Your is producing a tiny wisp because it's running at 1.5kW and burning hardly any gas and consequently very efficiently.

Point is that unless your boiler can modulate that low, and AFAIK most can't, then you'll never get it producing no steam, so there's no point trying. For the same system you could reduce the amount of steam, of course, but since you're only looking at 10 or maybe 20% at the outside savings, you'll not be reducing the amount of steam by a level that is quantifiable just by looking at it.

number of houses with huge plumes of steam errupting from them was staggering.

I don’t think plumes of water vapour from flues are any realistic indicator of whether the boiler is condensing properly or not.

The idea is to get steam to condense and even if you have perfect flow temperatures there will still be a reasonable amount of water in the exhaust because it’s warm. When that hits cold air of course the water trapped in it is going to become visible.

You can get an impressive plume just from breathing hard on a cold day.

Yes. You're doing well if the return flow is at 40C. You will condense a lot of vapour, but the fan is simply blowing the gasses over a heat exchanger. That's not 100% effective and even if it were it would only cool them to 40C so it will still contain vapour at that temperature. When it hits the outside air at 10C or 0C that remaining vapour will condense again.

Tangent - my hot water circuit - the heating coil via pump through the boiler - is full of bubbles. When the HW is being heated, you can hear loads. But not when the CH is on - that's silent. Ideas?

Ooft....
Just in, £450 for the month, even though the house was freezing most the month and we were away 5 days over Christmas.

Roll on spring and getting rid of the ancient old Potterton boiler. Secondary glazing being put in this week but draughty old Victorian house, not much more in the way of insulation options exist.

not much more in the way of insulation options exist.

Someone I work with lives in a similar house, and has had secondary glazing put in. They said that alongside that, the biggest benefit they've seen is from under-floor insulation (loft already done) and according to them it's made the floors comfortable, even the laminate/wood bits.

Just in, £450 for the month

£475 for us - 4 of us Victorian Semi East/West facing in all month. Thats £260 into £520 of credit. Lets hope it doesn't get to -9 again, the bill was £20 a day when it was, down to £12 now at +11 degrees. Temps have been 18/20 night & day with a boost to 21 between 16:30-10:00 consistently.

We were at some friends yesterday with the big 4 bed Victorian gaff with the 3 reception rooms, conservatory, high ceilings and open staircase/landing area + bats . Lovely place. Proper country living mag type place.

Owner did mention that December had cost him 800 quid in gas plus the wood from the trees they felled last year - to keep it at 17 degrees.

Moly, your popping in the ch coil could be kettling. Starts quietly then builds. I think its localised boiling due to calcium carbonate build up in the boiler. Fernox do a magic liquid called x200 that fixes it, takes a week or so.

Moly, your popping in the ch coil could be kettling.

If the system has been properly maintained with additives to stop calcium build up then not that likely.

We live in a very hard water area (sat on top of a chalk aquifer) and I've had to descale the 30 year old boiler at least twice with Fernox DS40 (basically acid). Not sure it will survive another session, the heat exchanger is weeping a bit now after the last treatment.

We have an open system, so if there is a small leak somewhere, it just refills and you have no idea it's drained all the additive and is running on pure tap water...

Crikey £450 - £475 for a house (large by comparison to my 2 bed rental flat) but I guess that must be norm for house that size.

Is the heating on constantly i.e. set to auto to maintain the temp?

I'm sure I'm preaching to the choir here, but even a modest duvet upgrade can make a big difference at night. I recently got this: https://www.marksandspencer.com/supremely-washable-10-5-tog-duvet/p/hbp60113585?prevPage=srp#intid=plpnav_pid_pg1pip6g4r1c2

And it's soo nice and light, puffy and breathable, and yet warmer than the £20 wilko jobbie I've been strugling with for a few years, which I'm sure is allegedly the same TOG (10.5).
I can happily turn the thermostat down to 15c overnight now.

Is the heating on constantly i.e. set to auto to maintain the temp?

Not here. We've not had the CH on for the last 3 days as we'd just tipped over the £200 mark for the month of December (gas and electric) and it's terrifying. Thankfully it's been above 5 degrees outside so wearing the big fleecy hoodies we bought have been sufficient. Average internal temp is 12-15 degrees depending on which room we are in. We have no thermostat so CH is either on or off, either via a timer on the boiler or manually.

Is the heating on constantly i.e. set to auto to maintain the temp?

Yes here, but at 14 degrees or less for the main part of the day, which is what many would have as their set back, 15-16 in the evening. During the cold snap rooms were dropping to 10 or below quite quickly during the day and ice inside the windows overnight, so turning off completely would have got pretty uncomfortable pretty quickly.

I'm getting use to the lower temperatures that my house is operating at this year.
Bedroom is ok around 10°c + electric blanket.
Living room is ok when the fire is lit. Otherwise it might be 10°c.
The kitchen dropped to 0.5°c on the window sill during the last cold spell but it's around 7°c normally.
Gas bill came in around £60 over 30 days inclusive of standing charge at the SVR.
Electricity was £40 over the same 30 day period.

Spring isn't far off 🤔 I hope!

Hmm. Pump wasn't backwards - boiler was plumbed the wrong way round. That's why I have bubbles in the hot water - it's now going backwards through the tank.

Someone mentioned earlier that steam coming out of the flue was bad - I just happened to look at my neighbours and saw steam pouring out so I went to look at mine - there was definitely some steam coming out although looked to be much less than my neighbours. I have turned the temp on my boiler down though... won't it be the case that steam will always be visible in cold weather when the hot moist exhaust gases from the boiler mix with the cold air or do I need to turn mine down more?? I did have it lower than it is now but the rads didn't seem to get hot enough so I turned it back up a notch...

boiler was plumbed the wrong way round

🙄🤦‍♂️😯

I have turned the temp on my boiler down though… won’t it be the case that steam will always be visible in cold weather when the hot moist exhaust gases from the boiler mix with the cold air or do I need to turn mine down more??

Yes there will always be some as a proportion of the exhaust gas. Lower return temps mean more of it is condensed and more heat is recovered from it. You turn your temps down as low as you can before a) it starts short cycling (turning off and on rapidly) or b) you find the house just isn't warming up.

You turn your temps down as low as you can before a) it starts short cycling (turning off and on rapidly) or b) you find the house just isn’t warming up.

Ah OK - thanks. Mine is probably roughly OK then...

boiler was plumbed the wrong way round

Is that those experts* FrankConway talked about earlier ?

* Paid per install new build installers doing it as rapidly as possible.

Just a heads up, I found my warm start / comfort mode has been turned back on at some point, likely during a service. This mode keeps an amount of water preheated 24/7 to allow quicker hot water to taps.

You may want to check your boiler to ensure that if it has one it isn’t being used unnecessarily, apparently makes 5-10% saving.

Mine burns 3 minutes every 90 minutes to keep 48l of hot water ready to go.......

I've just rewired the systems to put a stop to that.....

But think about that over a year.....it's a considerable number of days burning.... 1/2 of which when your asleep and 1/4 or more when your at work or not needing ho****er......

Mine burns 3 minutes every 90 minutes to keep 48l of hot water ready to go…….

That's probably more than mine is on for a whole year

Mine burns 3 minutes every 90 minutes to keep 48l of hot water ready to go…….

I’ve just rewired the systems to put a stop to that…..

Zilog. Depends on the boiler.

Mines a grant oil boiler....and manual states to link perminant live to the hot water live.

I just linked up a 2 Chanel thermostat with on demand hot water. (Drayton wiser)

With 50l stored outside in the boiler - I stopped heating it at 8.30 and at 13:30 I was still able to run a sink to wash some dishes and had to use cold to make it manageable.

If I need more hot water than that 50l can provide I need to manually boost it. - baring in mind if I drew a sink full at 9.30 it would add equivalent cold from the mains so it would cool considerably quicker.

molgrips
Full Member

Hmm. Pump wasn’t backwards – boiler was plumbed the wrong way round. That’s why I have bubbles in the hot water – it’s now going backwards through the tank.

Out of interest - does the feed leave from the top or bottom of the boiler?

I can’t see any markings, nor any mention in the installation & maintenance manual of my boiler that describes which is which...

Out of interest – does the feed leave from the top or bottom of the boiler?

I can’t see any markings, nor any mention in the installation & maintenance manual of my boiler that describes which is which…

On mine, both come out of the top. The manual has multiple diagrams that imply which is which although it's not especially clear.

But I only got to that point by discovering the weird behaviour with the temperatures when I was trying to establish the correct temperatures. It was not doing what I expected, and I eventually realised that what I was seeing could be explained by the water flowing backwards. That's when I checked the manual.

Swapped the boiler pipes over, and 0ut the pump the other way again. I had to drain it because the membrane has split in the CH header tank. Pressurised it all and now I am waiting for the wireless stat to connect to its base unit before it starts up. It may explode.

It may explode

Dibs on the Mercedes. 😉

Dibs on the Mercedes

Thought it was a Passat??? 🤔😉

This is the Passat thread all over again 😃

Have I monopolised it? Or provided the entertainment? 🙂

Or provided the entertainment? 🙂

Depends. Was the radiator on either car plumbed in backwards? 😉

Don’t put ideas in his head…

Smart meter is a fiver off £600 for the month. High and windy cold area south west of Glasgow, not wholly surprised given the minus 10 period early in the month.

Gas CH is on all day as I usually wfh and wife and boys are sometimes around and about during the day. Modern (20 yr old) 3 storey 4 bed detached, double glazing and doors all brand new.

Hive keeps house at 18 overnight, warming to 20 by 8am and 22 by 5 pm, cooling again by 11pm.

Was the radiator on either car plumbed in backwards?

I have no reason to think that, everything is working perfectly. I only mess with stuff when it's not working optimally, you see.

Hive keeps house at 18 overnight, warming to 20 by 8am and 22 by 5 pm, cooling again by 11pm.

18 overnight?!!
No wonder your bill is £600.

I only mess with stuff when it’s not working optimally, you see

A Mercedes then? 😜😜😜 (soz. Couldn't resist. Merry New Year 😁)

Hive keeps house at 18 overnight, warming to 20 by 8am and 22 by 5 pm, cooling again by 11pm.

I like! That's the sort of temperature I like.

My average day temp until heating starts is 13.5c and once heating starts it will go to 16c but only for few hours at night.

Delta T at the boiler has now gone back down to 10C which is what it was originally. Somehow the flow is more restricted in the reverse direction. The bubbles have gone from the hot water circuit though.

For some reason I can't explain, delta T at the boiler is much lower with the pump going the original direction but the boiler pipes swapped round. Somehow the flow must have been way slower in the opposite direction. I did think maybe the bypass valve was faulty but I've changed it and it's slightly better but still not great. It was originally about 8-10C, then with the pump flipped it was 20-25C. Now, with the pump flipped back and the boiler swapped correctly, it's 10-12C. I can't reduce the flow any more, otherwise it's too low and it short cycles like mad as the flow isn't even enough to cool the heat exchanger.

Weird.

It wa because the valve that sends water through the hot water coil is stuck open. Even when the rads are all cold, the return temp was 40C which isn't possible unless the water is coming via the hot water tank. So I isolated the hot water circuit and I could hear the pump sound change, and now the DT is back where it should be.

£185 gas/electric for December. Probably £40 of wood on top. Running the wood burner halves the gas usage for a cold day.

£300 Gas & £75 Electric for December £775 in credit before that, at least one of us WFH each day, all 4 of us off work/school for past 2 weeks, hoping Jan will be milder and I'll be in office more.

£115 combined
460kwh gas ch and hot water
129kwh electric, lights, tele, oven etc.
Ok, so maybe 100 hrs of wood burner use in that figure, but my wood is free.
Not horrendous at all.

Electricity: £23.25 for December (combination of some solar but mostly battery storage).
Oil: Not sure. Probably about 2 litres / day, so £60-70 for heating and hot water.
No gas.

2L/day?!
Really?
😫

Can't be arsed to trawl back through various posts but, in response to one of my mine which referred to using experts, I wouldn't trust a middle ranking/middle class/middling ability IT 'manager' with my CH system any more than that they would trust me with their domestic IT set-up.
Molgrips has been a prolific poster - was your installation done by a plumber on a piece rate to complete an estate-wide target (think splash'n'dash in decorating terms) or was it by a specialist heating engineer?
If the former, which seems likely, you get what you pay for; it works - but inefficiently.
Your problem, not mine.

So you want me to try and find a specialist heating engineer to come out to my house and pay him to do.. what? Tune up my heating? It takes hours, essentially I'm trying to coerce a badly designed system to work as efficiently as I can. If you were a plumber, would you spend hours and hours trying out different settings, tweaking things measuring temperatures? If I asked for that service I'd get laughed at. Tradespeople don't do stuff like that. They'd go 'well mate this is crap you need a new boiler/a whole new system', and they might be right. But I simply haven't got five grand for that.

So why not learn how it works and figure out how to optimise it? Are you suggesting I'm not somehow capable? I suspect you are with this comment:

I wouldn’t trust a middle ranking/middle class/middling ability IT ‘manager’ with my CH system

Is that what you think I am? I do work in IT but I'm not a manager, or a "manager". My job is to diagnose and fix issues with systems. The ones I work on are software, not heating, but the software is MUCH more complicated than a domestic central heating system; the process of understanding and figuring out what's wrong and what can be done is pretty similar. So yeah I'm confident that I have the intelligence and aptitude to learn about what's in my house and improve matters. You don't think that - but I'm not sure why.

Do you pay people to do everything for you? You take your bike to a bike shop all the time? Do you pay a gardener? Do you pay a decorator to decorate? It must be nice to be that rich. You may have overlooked that this system was recently "serviced" by a well recommended plumber. I was expecting him to at least clean out the combustion chamber on my boiler, but he didn't. If he had he would have noticed how screwed up the system was. He didn't do any diagnostics other than put his hand on a radiator. On the other hand, over the last couple of months I've found and fixed several small faults and one major one, and tuned the system for much greater efficiency - and it's cost me less than £50 in tools and materials.

I've got the controller set to 18° for most of the daylight hours into mid evening, and 14° for nighttime. That seems to keep the house pretty tolerable.

November's dual-fuel bill was £170. December came in at just over £270, and we were away for the Christmas week (I'm sure I put the controller in 'holiday' mode at a low target temperature for 6 of those 7 days) so the cold 10 days or so in the early part of the month made a big difference in Dec.

17 feels a lot cooler when it's mild and damp than when it's cold, I reckon. I've put mine up a couple of degree since the cold weather - although obviously far less gas is burned in milder weather even with the increase.

frankconway
Full Member

Can’t be arsed to trawl back through various posts but, in response to one of my mine which referred to using experts, I wouldn’t trust a middle ranking/middle class/middling ability IT ‘manager’ with my CH system any more than that they would trust me with their domestic IT set-up.

But the premise of heating system installation has been dumbed down so far that even an ‘expert’ doesn’t actually know much about the system. With the 10 week wonder courses being so acutely targeted to achieve maximum compliance and pass rates, Dunning Kruger is rife!

As a professional cable muncher, it galls me every time I see a ‘central heating wiring centre’ (box of spaghetti with a strip of choc blocks). This could very easily and for not much extra cost be improved markedly, both in terms of neatness and electrical safety. It could even be made with proper push fit terminals that would claw back cost on install time - so a win win.

Now things have been made even worse by the advent of smart heating - no it ****ing isn’t smart or it would actually take control of the system properly rather than piggy backing off the thermostat!

Find me a tradesman who isn’t just someone with a bit of experience who is willing to have a go and I’ll bite your arm off…

So why not learn how it works and figure out how to optimise it? Are you suggesting I’m not somehow capable? I suspect you are with this comment:

Don't feed the troll. He's already called me an idiot further up the thread for living in a cold house without knowing the first thing about my financial situation.

I put X400 cleaner in the system and the instructions say to leave it running on full for 2hrs, so I put it up to 20C and turned up the flow. It's now 22C upstairs and I'm roasting. How do people live like this?

How do people live like this?

I have no idea. I was staying with my dad over Christmas and he left the heating on one night by mistake. I woke up in the middle of the night absolutely roasting and that was 'only' 18°C!