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

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.