marshian

Similar arrangement for me but only time I use the immersion is when the HW/CH system is drained down for changes in the summer. My thermostat is set to 55 Deg C it's only a fairly short element maybe 40 L but that's enough HW at 55 deg for two showers or one shallow bath (I have a tank temp display and from memory the thermostat was quite accurate v the temp sensor) I can't help with re-heat set points as we heat only when (or just before) we need it so I've never noticed what hysteresis is applied

My question as far as you wanting to run at "low flow temps" are concerned is just how low will your oil boiler go down in terms of flow temp? I think this is an important point as you need to size the rads for the lowest realistic flow temp that also keeps the boiler happy I heat with gas and previously had a glow worm condensing boiler that was oversized for the house 24kW - I upgraded all my rads to match the heat loss at a flow temp of 40 deg C but realistically 48 deg C flow temp was as low as the boiler would run without excessive cycling and I ended up running it slightly higher and controlling room temps with TRV intervention (which isn't great for cycling). Moving to a new gas boiler (I wasn't brave enough to go ASHP at the time) it happily runs in from mid 20's to low 30's (Weather compensated flow temp) - only had to change one more rad to balance the house warm up (one room took way longer to get to temp) most TRV's are set to elevated target temps that can't be achieved in order to minimise circuit shrink due to TRV's shutting down. All Rads are fed with the flow they need for the WC flow temp although I am planning to improve this area as the Drayton EB4 TRV Bodies only have 6 flow settings and I could do with a slightly finer adjustment on a few rooms so I'll be changing a few for Danfoss RAS-B2 TRV bodies as they have a finer adjustment for flow rates House is heated 24/7 no set backs - it's way more comfortable at a lower room temps because there are no temp swings, In the heating season the boiler cycles once per hour max - the length of the cycle determined by the heat loss If the old room comfort target was 22 it's now 19 to 20 max House is 4 bed detached - extended with a 2 storey ext - is a stupid T shape with several rooms having 3 external walls - some insulation improvements - floor area total across two floors is 113 m2 and peak heating at -2.5 is 39W/m2

just for info I have a lot of data on gas usage for my house and one thing that really stands out is summer DHW usage is very very different to winter DHW usage. in summer tank losses are lower due to higher ambient temps in the house water from the mains can be 10 deg higher in temp coming into the house typically my summer DHW usage is 3 to 4 kWh for the heat up - Winter it's closer to 5 kWh - that's a significant % increase that you probably need to factor in MCS I agree is a bit crap - worst case on worst case - might be worth ignoring the grant element and pricing up what you need without EPC pretty much fiction and not really a good guide

Still here - watching because I want to see a happy ending…… prob page 1367 at this rate 😉

Separate pump for rads? Turn pump speed down and or open up lockshields and run rads same temp as UFH if sized correctly I hate system noise it’s a sure sign something is working harder than it should

Anaesthetic hasn’t worn off yet so currently no pain at all - pretty sure that will change soon

Might be a few days before I start back on it surgery I’ve been waiting 2 - 3 years for I reckon @JohnMo will have his finished before mine 🙂

I've used two of these in the past for an awkward soil pipe to pan angle - try to get one with ridges on the rings that lock up the joints as the smooth finish ones are much harder to get tight. (Flo Plast ones definately have that)

Then I think I'd be avoiding them and going for a supplier of known and guaranteed suitable material

If you have a heat loss (w) required by the room then it really is simple Lets take the example of the Room 1 - from the table you supplied heat requirement/loss is 612w So you need a radiator that supplies 612 w at your target flow temp Radiator outputs are normally stated at Delta 50 (Flow temp 75, Return Temp 65 so mean rad temp 70 Deg minus room temp 20 gives difference of 50 Deg. Rad outputs by size and type can be found here https://www.stelrad.ie/wp-content/uploads/2015/08/Compact-K3-Technical-Specification-Brochure.pdf Taking a T22 Rad (double panel / double convector) which is 600 mm tall and 1400 mm wide it has an output of 2.425 kW (2425 w) at Delta 50 Correction factors DT50 is 1 DT45 is 0.872 DT40 is 0.748 DT35 is 0.629 DT30 is 0.515 DT25 is 0.406 DT20 is 0.304 At Flow temp 45, Return Temp 35 so mean rad temp 40 minus room temp of 20 gives a difference of 20 Deg (or Delta 20) so the correction factor for that is multiply the original rad output by 0.304 2355 multiplied by 0.304 is 737 w so a little over what the heat loss required is so you could reduce the size a little but I'd go a little bigger everywhere and then tweak the flow temp back a smidge. The key for me when up-sizing rads is to try and ensure all are up-sized by similar factors for all the rooms - I made that mistake myself in not thinking about whole house heat up being balanced. With ASHP your rad flow temps and return temps are going to be a lot closer than the 45 / 35 but the important thing is the radiator mean temp so a rad is going to give the same output at 45/35 as it will at 42/38 or even 41/39 If you are looking at designer rads, vertical rads or towel rails up-size a little bit more because in my experience they are a little optimistic in terms of output and that impact gets worse as flow temps get lower Highest Flow temp (central heating) that I ran my gas boiler at through Dec, Jan and Feb was 34 deg C - house is all rads (no UFH)

And done……. well the big lift is done rest is down to me

Lift planned for tomorrow a little more clearance created today

they are an absolute cow to fit which is why the fitter didn’t use it - plenty of soap and a steady equal force - especially when doing two sides at same time

Don’t they say the expensive part is getting out of the ground - well done - I’m sure it will be plain sailing from now on

Wall mount / spacer complete yes it took me all day - I’m a measure 100 times drill or cut once kinda guy (plus manhandling the beams on your own is hard bloody work) Mrs Alien is 4 ft 10 in socks and has the lifting abilities/strength of a small hen Doubled up beam both are 2940 x 170 x 45 mm in new money. First one bolted to the wall in 4 places with 12 x 100 mm thro bolts. Second beam coach bolted thro both with M8 coach bolts. Now I’ve got clearance for the down-pipe behind the pergola wall mount. Next I need to find some willing friends - it is a three man lift and there still isn’t a lot of wiggle room….

The intention is to have no legs touching the decking (shortened to minimum and then wall mounted is the plan) I can shorten the legs without voiding the warranty but I can’t make any alterations to the roof section without losing the warranty

clearance achieved Finished height will be above them wall mount end is the tricky bit I have to fit a 3000 mm width pergola in a 3070 mm gap and there is a 68 mm drainpipe there too I knew it was gonna be snug but I’ll find a way to make it work

It’s all getting a bit tight here

The video “suggests” doing the wall mount next - so I’m going to ignore that - the decked area has a fall on it for drainage so the “suggested” height might not be right for the location (I already know one of the legs is gonna be in the middle of my garage side door so l’ll need to get creative there (3m x 3m) cardboard is 3m from mounting wall hahaha

it’s been on Mrs Alien’s list of “things I want” for a while so far I’ve got two legs assembled 🙂

Current area For the last 10 years we’ve had a sail over the area but they don’t last long (2 years at best) and the water run off in a downpour soaks the walls so we tried a mesh one which was better for not soaking the walls but not great for sitting under it when it rains Bought a pergola from a well known brand and it got delivered this week - today the plan is dodge the showers and see if I can get it installed un-packing the seven boxes took a while Then clear the area ready to start No written destructions are supplied - no packing list - apparently I have to download an app and watch a video and we all ignore destructions anyway so how hard can it be!!!!

Drove past the cherry tree pub yesterday - wondered how close you were to it - didn’t have chance to do a detour (car collection caper) but next time I go and see my folks in Rushmere St Andrew I’ll give you a message to see if you ate going to be about?

Going for surgery next Friday (sort my finger out - at last) so I’m owt for this month

I think Mrs Alien has one of those she bought for a bird table - I bet the battery is dead tho

Not heard that before - but we can be scientific about that and put it to the test because one is painted the other isn’t (because I only had leftover paint and as the ply had been dry stored for a while it soaked up the paint and took a lot more than expected)