DundeeDancer

They look like Drayton Lifestyle, in a rental flat so not so easy to check. 🙂

The problem system has a leaking TRV in bedroom1 and in the bathroom the radiator is no longer heating up which also has TRV. The TRV’s are the same age as the radiators i.e. 28 years old. New boiler put into the system 6 years ago. Wondering if one TRV needs to be replaced does the whole system need to be drained? If so maybe replacing all the TRV valves in the system would be wise?

Maybe I’m missing understanding these EPC calculations are doing but they currently don’t make sense to me and I wonder if they make more sense to others? I’ve just looked at a EPC for a neighbours flat that just went on the market this week and the calculation goes like this:- Page 1 Dwelling type: Mid-floor flat Date of assessment: 20 February 2023 Total floor area: 95 m2 Primary Energy Indicator: 234 kWh/m2/year Page 3 Space heating (kWh per year) 12,707 Water heating (kWh per year) 1,992 Page 3 seems wrong to me, for Space heating should it not be Total floor area: 95 m2 * Primary Energy Indicator: 234 kWh/m2/year to = 22,230 kWh per year? Gas boiler in flat is probably 80% efficient, so per year for combined water and space heating one would be using approc. 29,066 per year. Usual energy estimates are for 3 years so that would be 87,200 kWh and current gas prices per kWh are 10p so that would be £8,719 for space and water heating not including general electricity use but the estimated energy cost for 3 years given on the EPC is £5,934, seems well short to me. So the £ estimate being off I’m not to surprised at but the simple calculation from floor space to yearly space heating should be bang on at 22,230 kWh per year and not 12,707 kWh? Also when I bought my apartment which is very similar to the flat above, my EPC stated the Primary Energy Indicator was to be: 132 kWh/m2/year, so that’s a big difference, turns out 234 kWh/m2/year is fairly accurate as I did use 22,000 kWh in my first year of staying here. I’ve managed to get that down to around 16,000 kWh with new boiler and single room MVHR but still far in excess of the promised 12,936 kWh on the EPC which came on the home report when I purchased the appartment. Best wishes, DD 😎

I'm good thanks 😊 Hope you are recovering well from the post traumatic stress of having to deal with contractors and utility companies all over again 🙄 I guess it’s all relative on the MVHR side, beefy compared to my single-room heat recovery fan but maybe small compared to the blower in your own home.

I've not been on Buildhub much over the last few years but I've often wondered if you had started work and I have been checking on Googlemaps and then I seen a skip on there and think AliG must have started. Then I look on here and your nearly finished and it looks amazing! 🤩 Is that quite a hefy MVHR unit installed? Be interesting to find out how well the house performs this winter. 🤓

The modern cavity foam fillings are amazing, in your shoes I would be looking for a product like this:- https://isothane.com/products/technitherm/ The foam would be a complete barrier to dampness traveling across the cavity and the foam actually binds to the walls together making them stronger! I wish someone would come and put the foam into my walls but finding an installer can be tricking depending where in the country you are. Best of luck, DD 🙂

I know, but he was like 7 foot tall and a foot wider than me and he didn't look like he wanted to talk sense so I made a tatical retreat 😊

He said he would not be able to guarantee that there won’t be voids in the insulation if the polystyrene boards had possible moved. I suggested the foam expanding force should move any loose boards firmly against the inner cavity wall and so it shouldn’t be an issue but he said he wasn’t interested in such a job. I said well maybe in a few years time there will be better techniques for this type of scenario but he just disagreed and said it was impossible, with that mind-frame I thought it best not to discuss it any further and thanked him for his time.

We don't seem to have any good installers in Scotland yet. I had one guy visiting my development today and then he ran away as soon as I said there was 20mm polystyrene boards in the cavity already, so it's just the rest of the cavity to fill, another 80mm of the 100mm cavity. The installer was saying that's not possible but I had already been told by the isothane manufacture that it is possible. The installer also was unwilling to give me a ballpark price, I wonder how much it is on avarage per-meter-cubed for this closed cell foam. Would be great to get the foam installed, the brick work is quite porous and the wind just seems to get into the cavity and takes the heat away from the walls.

Is @AliG SMART enabled now?

Is the wait nearly over? Ovo now want me to fit a smart meter. I'm not that keen as I like having my dinner at dinner time, not at 2am in the morning when the electric rate is affordable.

Yes I’m coming to the same conclusion that it is the expansion vessel that is playing up. The boiler is serviced by British Gas at £240 a year with a £99 excess charge for any required fixes. BG did a good service just over 2 years ago but the last service about 2 months ago was a contractor brought in due to covid absentees, by the time I got off my work call he was all packed up and when I mentioned the changes in water pressure he said he couldn’t see anything but if it worried me then to raise an investigation call…hhhmmmm The Expansion Vessel part number 87161425060 is obsolete on heatingspareparts.com but available at plumbase for £82. So stock for this model of boiler seems on the way out so that’s another consideration on replacing the whole boiler. We seem to go through 20,000 kWh of gas each year, a new boiler with smarter controls and thermal values attached to all radiators we might be able to save 20% on gas use, which would currently be a yearly saving of £153. Couple that with reduced maintenance cost of having boiler serviced by an independent with Vaillant 10 year warranty that is another £176 saving a year. So the £3,500 installation would pay for itself in just over 10 years. I had hoped to get in front of the cold weather rush for replacement boilers but I’m getting the feeling there is a big demand for boilers now as it took my trusted installer much longer to respond. Previously I had installed in 2018 a Vaillant with vSMART controller in a flat I let out and it seems a nice set-up but this time the installer hasn’t yet given me options on different boiler makes and controllers like they did last time so doing a bit more of my own research now. I’m going away on holiday for a long weekend this coming weekend to Sunny Stonehaven, that will give me a bit of thinking time. After that I’ll probably just get BG in to fix the Expansion Vessel and live with the boiler for another year or 2 and then get one fitted outside of the busy months so I get a good installation completed.

I’m starting to plan on replacing the aging boiler in my 98m2 apartment, which is a Worcester Bosch 35CDi commissioned in about year 2000. The Bosch is around 80% efficient even though it is not a condensing boiler. I’m not sure if that efficiency drops with age but the water pressure within the system is getting a bit erratic, when the CH is on it goes from 1.1 bar up to 2.3 bar and when the system cools down the water pressure drops down by 0.5 a bar over a week, so I need to keep topping up from mains feed. Over the summer the water pressure has been fairly constant when only using the shower but now the CH is coming on more the pressure is dropping more, hence the research into getting a new boiler. Currently need a big boiler as apartment only has 25mm of Polystyrene sheeting for insulation in the cavity and brickwork seems fairly porous which lets the wind chill the walls. Planning on getting the other 18 residence to sign up to filling the rest of the cavity with Polystyrene beads but when we get around to it is anyone’s guess. So I'm currently thinking on a Vaillant ECOTEC PLUS 832, seems a really nice boiler. I like that it's a bit quieter than others, seems to have good modulation and the stainless steel heat exchanger will likely last a long time. The ecoTEC 835 exclusive Green iQ also loks good but not sure why it is approx. £300 more expensive and what real benefits it would bring. I’m also confused on what controller would give me the best efficiencies and how they really stack up in price comparison once all the separate components, hence the question around:- “Vaillant controller vSMART vs sensoHOME RF vs sensoCOMFORT RF”. My gut feel is that vSMART gives most bang for buck but it doesn’t look as pretty as new senso controllers. I have a pipe dream to one day put underfloor heating into this apartment run from this replacement boiler so the sensoCOMFORT controller may be best for that plan but with the insulation in the flat being so poor, underfloor heating seems a lifetime away at the moment. Also feels strange to be thinking about a replacement gas boiler when there is so much talk about heat pumps or hydrogen boilers these days but the reality is I need a good boiler for the next few winters until the insulation gets sorted out. So a good gas boiler with good modulation seems the best answer for the moment. Mind you the installation quotes are coming in at around £3K which seems high for fitting a £1,200 boiler but that might just be the going rate these days. Any comments appreciated. Esp from Boiler super hero @ Nickfromwales Thanks DD ?

So would you say it is reasonable to have 4.5 bar coming off the main into one’s property and having that pressure in the domestic pipes is a little high but still OK? My flat seems to be dealing with that pressure OK so I don’t see the need to add to the system a Pressure Reducing Valve. My neighbours are suffering a bit from water hammer but maybe their systems have less room to flex than mine / less expansion built in that my plumbing & connected appliances have.

Interesting thread. I was starting to think our mains pressure within our flats is high at just over 4 bar. A plumber is telling us via the factor that to reduce "water hammer" from some of the flats we should all (18 flats) fit a PRV, just after our own individual flat stopcocks. I'm not to fond of that idea because that would be 18 new points of potential failure in the plumbing system within our building envople. In my mind a better solution would be to fit in the garden somewhere just one master PRV for the development which would take the pressure down from 5 bar or so down to ideally 2.5 bar. Thinking 2.5 bar is optimum pressure for domestic use? That will still give more than enough pressure for showers heated up from combi boilers etc. So yeah interested to hear where you finally choose to place your PRV Ralph. DD ?

Thanks for posting the link Iceverge, I was just searching for this type of thing today due to me recently installing a single room MVHR fan and me not being too impressed with it so far. I was trying to find out if any institutions independently tests and publicizes these MVHR products. I wonder if the Passive House Institute database figures are just collected for the manufacture specifications or if the Passive House ran tests to confirm the figures? I don’t see any single room MVHR fans or Vent Axia items listed ? Cheers, DD.

Hello Marcel, I have stayed in a few nice guest houses that have had MVHR installed (new builds and retro-fits) and when staying at these places I tend to take my trusty CO2 monitor just to see how things preform. With me and the wife sleeping in these rooms we have found that at the start of the night when we haven't been in the room for ages the ppm start off at about 500. Then pretty soon once we have nodded off to sleep the ppm raise up to just under the 1,000 ppm mark and hover around there till breakfast time. When I spoke to the owners though they did say they ran their systems at 20% or even at 10% capacity overnight to keep the noise levels down when sleeping, which I did furrow my brows a little at ? I've just fitted a single-room MVHR fan into our main bathroom as an interim measure until the time is right to do a deep refurb on my own place. I'm not too impressed with the single-room MVHR so far but it's only been 5 nights and maybe I'm expecting to much for a £300 fan but I feel my own thread brewing ? Best of luck with it all, DD.

Skimmed the book and not many pictures or diagrams but the words so far are interesting.

Switch the isolator switch off for the oven, then just to be careful switched the circuit off at the consumer unit. Snipped the old oven lead about 18 inches from spur connection. Slid out old oven. Stuck on a socket to the old oven cable, taking care to make good connections. Attached tester plug and powered on, all OK. Switched off isolator point. Slid in new oven and plugged into new socket. Powered on all good. Nothing overheating. Happy as Larry ☺️ DD

Electric fan oven has stopped heating up on fan function but other functions still work ok. Time for more efficient model anyway, so new one order that has the same 13A rating. Old one is wired into the circuit but new one comes with fitted plug. In two minds whether to strip the plug off and wire into the circuit as existing oven is. Or to wire a cable and socket into the existing oven part of the circuit and just plug the oven in? I’ve got one of these trailing socket things in the garage which I think would do the job as also rated as 13A. https://www.diy.com/departments/13a-1-gang-trailing-socket/170998_BQ.prd The consumer unit is quite new and I have figured out the circuit to switch off before I do any work and I have a good DIY book that describes cable thickness to amps rating. So just wondering what more experience DIYers would do? Thanks, DD ?

Same as me but every year I tell Plusnet that I will leave and they bring down the price to a sensible level. Currenty 18 month fixed price @ £25 for Fibre 40mbps, free evening and weekend calls. This year I also managed to get the router updated. You need to tell them the deal you will move to if they do nothing, I usually quote TalkTalk and when they say you know how bad they are I just reply, well I had them for 5 years before and they were fine so give me a decent deal. Go get them Jeremy!

To clarify my understanding of when it is not worth installing an MVHR system is when there are to many gaps in the fabric of the building that allows a certain percentage of cold air to be sucked into the building through the fabric and not via the MVHR inlet manifold. So this external cold air is just seeping into the building without going past the MVHR heat exchanger. In this scenario a few undesirable processes are occurring:- 1. Cold air is seeping into the building without being warmed up by the MVHR system so cold drafts occur in the dwelling. 2. The stale air does not move so readily between the rooms to then be used by the MVHR system to heat up the fresh air from the MVHR inlet. These points mean the efficiency of the system is significantly reduced and with the volume of air that goes through MVHR system it may well be possible that the MVHR system then starts to significantly chill the dwelling. The only way to stop this drop in efficiency of the system is to ensure there is a good airtight barrier in the dwelling apart from the MVHR systems inlets and outlets. The only way to get to the point of sufficient airtightness is to install an airtight barrier behind plasterboard and ceilings etc. So this takes a deep refurbishment project to install correctly or to be installed on initial build. In summary I believe installing an MVHR system will always help with air-freshness and de-humidifying a dwelling but if the air-tightness of the dwelling is not up to standard then in effect the system will be bringing to much cold air into the property via the gaps in fabric of the building and chilling the building. This is my laymen’s understanding of why installing an MVHR system may be folly. I do wonder if I am missing any other points? Many thanks, DD.

I use one called Green Eye, pretty much the one below. It's been pretty good. https://www.amazon.co.uk/Gain-Express-Temperature-Laboratory-Classroom/dp/B00OXMVJME/ref=sr_1_51?keywords=co2+monitor&qid=1576773418&sr=8-51

Interesting post there Jeremy, after I complete my PhD into human biology maybe I’ll understand it a bit more. ? Not sure what to make of the new a/c unit in my office, it’s blowing away making a din of about 52dB, the temp is a chilly 21.4c 1,300ppm Hum 42%. Yesterday it was quite quiet, 24c, 900ppm and it felt normal to me. Strange I feel cold here at work at 21.4c but feel fine at home at 21.7c without a/c. I can’t figure it out.

From what I've read 800-900ppm is about ideal in that it means the room is not being over ventilated. I haven’t got my figures to hand but in my current bedroom if we sleep with the door closed then by around 7am in the morning the ppm will be around the 2000 mark. Also if it is cold outside say under 4c then the windows will covered in condensation. With the door open all night it will average around 1500ppm at 7am which doesn’t feel to uncomfortable. Not that long ago the wife and I went and stayed in a posh hotel up in the Highlands, was a bit of a drive to get there but when we did I had a little lay down on the bed and before I knew it I was snoozing and very doozy. I then looked at my CO2 monitor I thought it must be faulty as was reading about 3,500ppm. The room couldn’t have been ventilated from the night before and the lack of oxygen was making me sleepy. ?