marshian

Very good point - my current cyl would be almost useless with an ASHP - the coil is tiny and incapable of transferring energy quickly In summer I heat HW with a 62 Deg flow temp and it takes anywhere between 35 to 45 mins to get the cyl back to 50 Deg C (I do this to maximise the condensing benefits where the boiler doesn't have a whole house to maintain temp (because summer) In winter I heat HW with a 80 Deg Flow temp and it's done in 20 mins because I want the boiler to get back to CH asap (low temp heating needs to be continuous to replace the heat lost. (at 80 deg flow temp it's condensing for maybe just a few mins out of the 20 mins cycle) An ASHP compatible tank with a 3m2 coil would solve the issue but it's ~£1500 plus install costs. It's one of the reasons I am investigating a PHE if I can improve the HW reheat whilst running lower boiler flow temps I can extract a little more efficiency out of the boiler even in winter. If that works I only need a direct UVC with no coil and that's a heck of a saving even with the cost of a PHE

Yes and Yes - very house and heat loss specific - I effectively went for same size T22 to replace T11 - only one rad needed to go from T11 to T22 and then T33 (cos it got extended) I didn’t design the system to run at 25 to 35 deg flow temps it just happens to be the range that heating 23.5/7 with WC works (30 mins for HW daily) I have 3 column rads in the house and whilst they are also an equivilent % upgrade 2 of them are single column and they really could do with being double column rather than single because they only just cope - I think the claims for heat output are based on T50 and when run at lower temps they aren’t as effective

Sorry it wasn’t a criticism of your comment - I think you made a valid point that it’s easy to make solving a problem complicated Urban Plumbers videos are often good for “out of the box” approaches to heating/hot water solutions to specific customer needs that aren’t complicated which is why I’ve watched every single one he has done - I remembered this one so linked to it.

It all fitted in a tiny bathroom on DHWP - I thought it was very simple (whilst being bloody clever)

He want 4 simultaneous showers - so he will need a bigger tank heated to a higher temp so he doesn’t run out of water during showering - urban plumbers did an install where the gas boiler was set up on HW priority and a small tank was mated to a gas boiler and it could reheat HW as fast as it was being used - like a huge storage combi but without the peak flow limitations of a combi (the biggest of which can’t supply 4 simultaneous showers) Thats the way I would go in this situation

What temp are you currently heating it to? Most HW uses are blended 60 deg water with 20 deg water at a 50/50 mix gives shower temp water If you can use 140L in 10 mins that's 280 Litres of shower temp water and 28 Litres per min (assuming multiple simultaneous showers) For clarification 2 people living in one house - 115 Litre tank heated to 50 Deg once a day and that's 2 showers each per day or one long hot bath so I'm think your water usage is quite high

So size the rads to work on the same low flow temp as the UFH based on the heat loss of the upstairs rooms (allow a bigger oversize for bathrooms because ventilation losses tend to be larger - extract fans / opening windows etc)

Thank you - I hope you have a little more clearance in your alcove than I had 🙂 you really do need a bit more than 70mm for wiggle room!!!

This has taken a while…… Support brackets fabricated in 5mm stainless steel then welded up Fitted them and was very pleased with the overall look Mrs Alien not so happy….. so I sent them off to be powder coated in white to match now fitted And the other side you won’t actually see much of them the first one will be almost covered by the garage fascia board and gutter the second one by a water removal pipe stopping it draining onto the decking better finish the rest of it now

I'm doing whole house (inc bedrooms) with radiators without TRV intervention - Yes I have TRV's right now but They are set to a stupid upper limit so actually have no functionality - I could just as easily replace them with decorators caps - Weather compensation combined with individual radiator flow rate control works perfectly

Works for me 🙂

Don't even bother to try Stick a low branch end into a pot - it will root itself - once rooted cut the umbilical cord so to speak and you have a new fig tree to pass on to someone else - done about 10 so far!!!

Put it in the ground and put the root ball in a stainless steel washing machine drum Add a 100 mm soil pipe to the bottom of the WMC drum poking out the top so you can provide the required water (up to 2 gal a day is needed)

1st Thursday was last week Can't do this week - I'm at Prescott Hill Climb orgainsing a car show

As always when buying baths try one before you buy one - yes on line is cheaper but if someone likes a long soak in a hot bath then you will never hear the end of it if the bath is uncomfortable to lay in for any length of time. if its just for showering next owner will find out if it’s comfortable

In other news Boiler had it's first service Gas turned off and disconnected from burner All electrical connections to burner and ignition removed Burner came out and it and the ignition electrode were cleaned Heating coil scrubbed with plastic spinny brush on a drill Burner re-fitted Condensate trap removed - emptied - cleaned and replaced (refilled with water) All removed connections checked - he found a loose/poor connection on the outside temp sensor so he cut back and re-did it. Boiler fired up and he repeated all the commissioning gas checks (hi and low flue gases) Boiler wasn't quite 1 year old and from arrival to leaving it was about 75 mins and £72 with the vat (he did say his service work is normally busiest in Sept and Oct and right now it’s fairly quiet for anything except new installs, mainly ASHP because of BUS grants) but I had the boiler purchased & fitted in July for the same reason I want any servicing to be outside the busy period. Scores on the doors from the boiler stats for one year Heating Demand Hours 4117 (171 days - I was initially heating to schedule and only moved to 24/7 in Dec 2024) Burner Hours 1917 Burner Starts 3965 Hours on CH 1683 Hours on HW 234 Average Cycles per day 11 (Summer HW process has driven down the average) Average Boiler Cycles per day in winter heating period 22

Blimey!!!

This is exactly my aim - minimal overshoot at the top of the tank - whole cyl heated to almost same temp at as low a flow temp as I can get away with in one burn cycle within the shortest time frame (ideally under 30 mins) If I can achieve that with current 13 year old copper tank (where I know my losses are still higher than a modern tank) then subsequent replacement of the tank for a more modern jacketed tank is hopefully only going to reduce the static losses and the efficiency of the HW heating isn’t going to change for the worse.

Stats from this morning (all Deg C) peak/end temps taken just before cycle ended start Tank Top (start) 31.3 Tank Bottom (start) 26.2 flow temp peak 77.5 return temp peak 66.4 Tank Top (near end) 55.2 Tank Bottom (near end) 47.6 my temp monitoring records all temps on the hour every hour (you can see current temp at any time but the data is only logged at hourly intervals) Does mean I have a really clear knowledge of my tank temp losses over time)

Oh and I appreciate what I’d like and what is actually possible might be very different (ie impossible)

I’m slightly confused (nothing unusual there!!!) water flow temp to the PHE has to be above the target tank temp no mater how efficient or how much surface area it has so if I want water at lets say 45 deg C then the flow temp needs to be above that I’m not looking to heat the radiator circuit with a PHE - the boiler copes nicely with a flow temp from 25 to 35 for the rad circuit (it doesn’t mind a delta of anywhere between 5 & 7 deg as long as the circuit is unrestrictive (ie full circuit available to it) needed to heat water today quickly this morning - tank temp start 25 deg (flow temp ramped to max 80) had a 10 deg delta at the boiler at the end of the 30 min cycle) and had the usual issue of a massive overshoot of tank temp (stat set to 50 deg) top got to 57 before bottom got to 50 and it used 4.88 kWh of gas heating with a lower flow temp (62 Deg C) stat would have switched off at 50 with virtually no difference between top and bottom of the tank and used 1 kWh less energy (this is how I do my water heating in the winter to shorten the cycle time and get back to CH before the house temp drops) My existing tank coil I think is maybe a 3kW one - certainly looking at similar tanks for sale the coil surface area is going to be maybe 0.5 m2 if that. I’d like to get away from high flow temps but still heat in a shorter time period - my thought was either new tank with heat pump compatible coil size 3m2 surface area or PHE with similar surface area and bronze pump to circulate Ideal world I’d like to achieve flow temp of less than 55 deg C and a target tank temp of 50 deg C with 115 litres of water at 25 deg C heated in a maximum of 30 mins max with one boiler cycle (ie it fires once and runs till stat satisfied - not cycle several times to achieve the target) If I tried to do that with current set up I estimate that HW cycle would need to be 90 mins and the boiler would fire maybe 3 or 4 times with ever shorter burn lengths and still wouldn’t achieve the target tank temp although it would probably be close)

thats how they ended up single mothers in the first place

How often do you boil the kettle when in the E7 period - gut feel says not as often as it’s boiled in non E7 period?

It’s ok it’s balanced out in the other bathroom they go up down 😉

I couldn't put my finger on why it didn't feel right it just didn't - it wasn't tiled in or siliconed to the wall but in hindsight the way a bath is used for a shower is completely different in terms of feel to when it's used as a bath - 80 litres of water and an 85 kg person laying down in it is completely different loading to zero water and an 85 kg person standing at one end with the bath supported by 4 points of contact aligned more to the middle section. Increasing the number of braces to 4 and feet to 8 really changed the solidity of the bath. One day I'll get rid of the cheap ass plastic panel and build a proper tiled one with the spare tiles I bought to do it and kept aside under the bath Yeah we all have one day jobs like that.............. But then again as Mrs Alien chose the tiles and they my my eyes squint and remind me of a stiff little fingers album cover I probably won't