marshian

Yes Ar*e of the pig

JG 22mm speedfit is 30mm OD and 22mm ID according to a quick google? Max Flow rate thro a 22mm ID pipe at 0.3 bar (ie 3m Head) is around 14 litres a min or 840 litre per hour OK you are going to have some restriction at the 15mm drop down but it doesn't seem to me like you need to convert to copper on the face of it I would but all my house is copper and I've never used plastic

Hmm that's a chunky thing........... any boiler or ASHP is going to love your system volume Their on line guide says at 15 deg difference between room temp and flow temp is 0.206 x T50 output so that's 412 W The Danfoss calculator I use says for a 500 x 100 x 250 column rad it's 273 W with a flow rate of 34 litres per hour but clearly they have a base line for column rads that has a lower water capacity/surface area

And that's been the case since condescending gas boilers were made mandatory for all replacements and new houses - the UK should have been embracing low temp heating and customers seeing savings from condensing - except the new boilers were set up at the same flow temps as the previous boilers Don't get me started on the combi epidemic where oversized boilers were thrown on walls and were sized for HW demand not CH Only 19% of my annual gas consumption is HW the rest is CH (OK just under 1% is cooking but that's really insignificant)

I hope mine isn't too criptic?? If it is I'll change it to the a*se of the pig which is how I explain it to anyone on the other side of the pond

966 width, 600 high? whats the depth? To get closest to 1974 W from a T22 at T50 it would need to be either 400 high by 1800 wide (1969 W) 500 high by 1600 wide (2092 W) 700 high by 1200 wide (2029 W) So that seems like a really high output for the size of the rad but I'm not familiar with column rads?? Differential Pressure is linked to pump head - for my rads I have a 1.8m pump head so I use 18kPa as my differential pressure for all my rad flow calcs and it seems accurate enough

Can you tell me the size and type of rad for a room or rooms because it's easy to work out what flow you need and as a result of the flow rates needed check the pipe sizes will cope. example a T22 600 high by 1400 wide running a flow temp of 35 deg C, a return of 28 deg C at a differential pressure of 30kPa would output 375 W when supplied with a flow rate of 46 litres/hour

cracking on at a pace - excellent - looks good

I thought it was more to do with highlighting that Electricity prices are linked to gas and as a result it's not a level playing field for ASHP or any form of electric heating at 5p per kWh there wouldn't be any need to achieve high efficiency SCOP/COP

yep for a floor with lots of foot traffic glue the joints... For a loft with virtually no traffic just screw (never know when you might need to lift a board for access)

South facing rear of the house with french doors in both Dining Room and Living Room means solar gain is a useful bonus but doesn't really overheat until we are out of the heating season. What has really surprised me is how effective WC is in meeting the heating needs there were only a couple of times when it got caught out with big temp swings in a very short space of time But my manual weather compensation that I was doing before would have been caught out too 🙂 I think that's the benefit of WC and 24/7 - house temps are amazingly stable and as a result you can run slightly lower target room temps and it feels fine. I'm comfortable in temps from 17 to 19 with no drafts (lack of air movement makes a huge difference to comfort levels at lower room temps) Downside is Mrs Alien is slightly more sensitive to room temps and to her "toasty" is 22 and "Freezing" is 19 but she's getting used to the new regime and back end of winter had stopped declaring the house to be "like an ice box" at 20)

I am using a little more gas but part of that is down to “learnings” during the heating season so up from 8500 to 9500 but 9000 would be a reasonable expectation For a boiler to condense the return temp to it needs to be below 54 deg. The lower the return temp the greater the condensing energy recovery

Similar situation with my house suspended ground floor with decent sized void under it - 75mm kingspan PIR between the joists made a massive difference to energy bills - rads all rooms no UFH Running WC flow temps max 34 deg c at -2.5 Don't discount rads as an option

Not updated this thread for a while but now the heating season is over it's time to consider where I go next - let call this an end of term report. Boiler review - Did I buy the right boiler Yes - unlike the previous boiler purchase. Very happy with it's weather compensation and low flow temp capability and by the time we got to early spring I'd settled on a WC curve of this. I still have a little niggle about it's output being a little higher than claimed min but it's close and I am running at lower flow temps. System improvements/changes I've ordered 9 Danfoss RAS-B2 valves to replace most of the drayton EB4 bodies (adjustable flow via selecting one of 6 orifices) Why? 1. majority of the rads are running orifices between 1 and 4 and in most of the rooms the difference between one setting and the next one (up or down) is too coarse and I need finer control to stop the rooms being too cool or overheating without TRV intervention. 2. I want to get rid of nearly all the wiser smart TRV's and replace with decorators caps and I can do that if I have finer control of the flow thro the rads. Leaving them on the rads just gives me an expensive battery powered room temp indicator (where I need to replace that batteries every 300 days) 3. Replacing the TRV bodies means a drain down and that's an opportunity to re-configure the rads from BBOE to TBOE and tweak a little more efficiency out of them (5%) and I think it might help increase the delta across the rads It's quite amusing to think 4 years ago I was 1. running a boiler that was capable of producing 5 times the energy compared to the heat loss of the house. 2. Running the boiler at a temp that was only ever condensing in the warm up phase 3. Micro managing room temps with "smart" TRV's to heat only when needed via scheduled heating (over zoning) to now 1. running a WC boiler at a max flow temp at -2.5 of 34 Deg C so is condensing all the time and running at 97% efficiency 2. Heating 24/7 with minimal zoning 3. Planning to drop nearly all the smart TRV's and just controlling the room temps with WC flow temps Weird journey when you think about it............

Back story here

I don't get a lot of turbulence with a vertical top mounted element and you certainly get a very defined stratification with minimal heat transfer to water - down side to my element is it's quite short, maybe less than 1/3 of total tank height so it really only heats about 50 litres max - just enough for two decent showers or a shallow bath

Oh I get that and 'it's why I might (in the interests of "science" ) move the bottom sensor up to a position on the outside of the tank level with the end of the immersion It's a top mounted vertical immersion in a 115L tank and it has it's own internal thermostat just as yours does Question will be at what point the internal thermostat signals re-heat and after how much water has been drawn off? gut feel from how we've used it before is you can pretty much use 70% of the water before it will kick in again and try and reheat so maybe 40 litres

OT I lived for years first on a Volvo 3.0 CD and then a Senator 3.0 CD plate was relevant to both 😉 rather than to me When I couldn't find another Senator that wasn't full of tin worm it carried on first on my BMW 740i and now on my current BMW "130i" I did get a daft offer once from someone who wanted it for their Audi A3 but I kinda like it and 30 years is a long time to have a plate

I don't think that would tell you anything meaningful unfortunately This is what I have on the tank (Library picture from a legionaires cycle to 61 deg C - followed by pouring a bath) the top one is looking at the top of the tank - the bottom one where the boiler tank thermostat is I'd need to put another temp probe in or move the bottom one up to roughly where the immersion element ends to get a better idea of hysterisis

Makes sense now I'd do exactly the same (I have OCD too - hence the plate on one of my cars)

Looks like I'm going to have a play with the original spreadsheet and @AartWessels web based app I originally did heat loss calcs with https://heat-engineer.com/en/ From memory £12 paid for a single one off survey - took a bit of time with a tape measure but the results for my submission were pretty accurate v real world energy usage over the winter and it felt like good value I've recently improved a few aspects of my house as well as moved to a low temp heating regime and I want to to do another heat loss survey to see what I could expect compared to the original Price now for a single user / single survey is now £100 not sure that represents good value any more

Well done - clearly the poorly installed installation was very much the driver for your heat loss issues - only thing I don't understand is why there is a mixture of materials - surely with the roof off it could have all been kooltherm PIR?

Brick acid will normally take off sealant - however it is very aggressive stuff - A friend of mine arrived on my driveway in a car leaking a lot of very hot transmission fluid - it went straight past the sealant on the brickweave and all the normal gunk/jizer oil removal preparations did nothing - brick acid worked but it's obvious which bricks were treated - the surface finish is very different

Do you live in an area that gets a lot of driving rain and or the house is in an exposed location?

couple of points 1. You could but the output might be horribly compromised - heat rises and doesn't sink so the top of the rad might be warm but there won't be a lot of heat traveling down. 2. Most "good" vertical rads clearly indicate inlet and outlet in order to work with the diverter that is installed in the rad (I'm not sure they can be fitted upside down either you need to discuss that with the manufacturer) 3. I've linked to my post about my experiences with a couple of oval vertical column rads as not all manufacturers have the same level of quality control and diverters are crucial on vertical rads in low temp systems 4. I'd run the pipes behind the rad and feed from the bottom (maybe paint them the same colour to hide them)