Alexx

Nice, thanks for taking the time to help me with this, much appreciated. What do you use to do these drawings if you don't mind me asking? I've ventured myself into sketchup, but that was a bit of a rabbit hole for me. I've got word back from world heating, they cylinder is a bit longer, and the immersion heater on the dome, plus they can do a cradle that only raises the cylinder by 10mm for some extra pounds. So far, this seems to be the winner. I just need to check if 25 metres of DN25 coil is good enough. I could not get further details from other manufacturers yet on this aspect. Joule emailed me yesterday that they do not have any technical details on their horizontal cylinder, but it works and I can trust them. How come a company that makes the damn thing does not have a single technical detail to pass on?!?!

Yep, metric all the way. Last time the Germans sent stuff to the space station in metric when the Yankees were expecting in imperial, that did not work well 😣 Thanks for helping, very kind of you. Highest point that you can see at floorboard level against the steel beam is 970mm, horizontally from that point measuring 600mm further into the eaves, it becomes 710mm. It I raise the floorboards and get the cylinder and close to the edge to my staircase as possible, it seems to achieve similar clearance. I've asked world heat about their options, they can make a cylinder with a 10mm low profile cradle and the immersion heater on the dome side, which would allow easier maintenance. I'm just checking how big the de-stratratification kit is to confirm I can fit it all. Worst case scenario, I may need to replace the 8x2s with 6x2s. I'm already doing 200mm between centres to be at the far extreme of over engineering it just in case. If after installing the cylinder I have some room, I'll add another layer of 50mm PIR

I tried that as well, but when doing ceilings, and in my case worst, slope, I can't get the can upside down properly to get the foam out. Why do they sell these acetone/propane sprays as foam gun cleaners? is dichloromethane (I had to do a copy and paste) one of those substances that can be used to make crystal meth hence the reason they do not sell it on amazon?

I do have, and I must say it is the most annoying job ever. Sticks everywhere, when doing the ceiling it is crap to get in properly, I can't get on with it at all. Cleaning the gun is a pain, you use the acetone spray and then eventually there is a transparent crust covering it, it does not matter how often you clean it just after use. Me and the foam gun do not get along.

Yeah, that is a lot of work in progress on my side. I must confess that I should have bought gapotape as the amount of mess and dust I'm making with the insulation boards is ridiculous when you try to friction fit them, and I'm using a festool specific for insulation, great kit, but next time I'm defo going for that damn expensive gapotape...

I guess with the de-strat pump should alleviate a lot that hot spot, which would also be applicable even for a vertical cylinder, I guess?

So I've got some additional technical details so far: Telford: Fabdec The guys from Joule so far have been useless, not technical details, all calls I make always end up speaking to someone that has zero knowledge. I get promised the "email" that never comes with all technical details for 3 days already, after 5 phone calls. I'm leaning to Telford so far as the standard horizontal heat pump cylinder is around £820 + VAT, I'm just waiting to confirm the cost to get the immersion heater on the side instead. Fabdec coil design does not seem that large to me, but I could be wrong. I just wish the coil could go further to each end of the cylinder. Joule gave me a cost of £2800+ but I found it for around £1800, but still without any tech details, I can't consider it. I'm now waiting for a few others like UKCylinders, World Heat cylinders, newawk and macdonald, then hopefully I can make a decision and buy it.

As an alternative to use 2 smaller diameter cylinders you mean?

That seems to be the general opinion I've gathered, as long there is a de-strat pump running when the cylinder is being charged, there will be not that much difference. After I've considered all options and the lack of commitment/info from Sunamp, I've decided to stick to a horizontal cylinder. I'm just trying to decide which brand/model I should go for. I have never seen it modelled, so hard to tell. Take a cylinder with a 0.5m diameter ad a 1.2m height. Assuming a U-Value of 0.2 W.m-2.K-1 Volume will be 235 lt. Surface Area will be 2.28 m2 Base of cylinder temperature, once settled, 36°C, top of cylinder temperature 60°C. Ambient Temperature 10°C. If one assume a temperature gradient of 20K.m-1 (about what mine is), then the power losses, when vertical, will be the sum of the top end, plus the area of the diameter (hoop), then the sum of the hoops, and finally the sum of the last band and the base area. Using a course 0.1m down the cylinder, the power losses are 18W, or if the cylinder is unused for a day, 0.44 kWh. Now lets turn the cylinder horizontally. Working out the surface area is not quite so easy here as for every 0.1m loss in height, the end area and the hoop area do not scale in a linear fashion, so I sketched it up in CAD, sliced it, triangulated it, then worked out the dimensions. Accumulative errors was between 1 and 8%, so shall use 4% as the error. The cylinder power losses are now 20W, 0.49 kWh.day-1. A difference of 0.05 kWh. The above is on a static model, but there will be some turbulence. With a mean temperature of 48°C for the vertical temperature, the mean density of the water is 988.7 kg.m-3, at the top of tank temperature, the density is 5.53 kg less, 4.48 kg more at the bottom. A total of 10 kg.m-3 difference The horizontal cylinder only has a 12°C temperature difference (because I used the same temperature gradient of 20K.m-1), so the density difference is only 5.6kg.m-3. Now without getting into Reynold Numbers and tangential surface areas, a simple way to model it would be to look at the difference in stored energy and the difference in mass as energy is the ability to do work, which can be reduced to moving a mass a distance. The vertical cylinder will have 233 kg of water in it, the horizontal one 232.4 kg, so 0.6 kg less. To move 1 kg of water, 1 metre, will take 1 joules of energy. So to move 232.4 kg 1.2 metres will take 279.6 J in the vertical cylinder. There is only 0.5 metres of height in the horizontal cylinder, so 116.2 J, so the turbulence losses will be in thee order of 42% less. So I would not worry about the cylinder orientation. I am going outside to sand some wood now the glue has set. I'm technical, but this definitely goes beyond my understanding I can grasp the idea, thanks for the extensive write up. I'll definitely re-read this many times once I understand the physics a bit better. I've been checking several models, they can customise the cylinder a bit and get the immersion heater on the side of the body, or even the dome. The rafters are 27.5 degrees. This is my space, with a 600x600 cardboard cut to give a better idea:

I decided to call Sunamp this morning and speak to someone on sales to get some better understanding about their product. Funny enough, no one to take the call... Really?!?!

Thanks, interesting report about it. I heard that is can only do full blast or nothing, like 2.8kw. Is that true? Does it not modulate? Yes I've put 8x2s every 200mm centres, they are about 1.8m long, then 22mm chipboard. One side on a steel beam the other side on the blockwork That is a very good point, I guess I can strap it and get 4 people to help but still a tiny dense box to manage with no handles. That is the part the makes me feel it is a no go. they have 3 models for samsung, daikin and vaillant, but they all need to ruin max temp from what I can see. The samsung needs to be modded to achieve sugh high temperature and I think that would negatively impact the COP. Slope starting from 95cm from floorboard, then going down at around 30 degrees, I'll take some pictures and post here once I do the cardboard mock p. It will just fit a horizontal, it would not fit any type of vertical. My idea is to store at 55c max or just go to that temp from time to time to kill legionella, 300+ litres, de-strat pump, the largest coil possible, the small feet possible to keep the cylinder in place without increasing the height. the stratification of water, as it is a larger surface compare to a vertical cylinder, that it will be less useable volume of water in practice. Energy loss wise, should be exactly the same, it is same cylinder just turned around.

I've been quietly reading lots of topics here about Sunamp as I was considering it an alternative for energy storage in my loft eaves. I should be able to get a horizontal cylinder to fit, just checking this at the moment with a mock up cardboard. The idea of Sunamp is great, but it seems the execution is poor. From what I can see it seems a bit of a beta/alpha product released to the masses with a "network" of installers and with little end user support when things go wrong. I can't find much on youtube about people showing their own installations, which leads me to believe no one does it. So back to my original plan, I can get a 300L tank in the loft, but everyone says for a heat pump, that is a no go. From what I can see, I just need a cylinder with a large coil made specific for a low temperature system, and perhaps a de-stratification pump. yeah, 300L horizontal won't be the same as a 300L vertical, but I have no other option. Any thoughts? Should I avoid Sunamp like a plague?

I was trying to find concrete/screed floorboards that can be used as the structural floorboard and at the same have the grooves for the underfloor heating pipes. The idea of using a concrete/screed floorboard is to have better thermal conductivity and less height instead of using floorboards and then a underfloor heating panel on top. There are regular chipboards for underfloor heating that I'm also researching about, but considering the pricing, it may be better to just use regular chipboard and then additional underfloor heating panels on top. If anyone has some advice on best options for underfloor heating in a loft, that would be great. I'm planning to use the same procedure on the 1st floor of the house later once we work our way down.

Thanks! I started looking for plungesaws, it seems I may be better off getting a second hand on ebay, still looking for a good deal

One of the sides of my wall is around 10mm off level to my door frame as I built up 3 layers of plasterboard with tecsound in between to lower the noise transfer, as this is a home office. I was thinking about how to fill this gap with a strip of wood, but I need to plain it at an angle and I've no idea how I can best achieve this. maybe there is a DYI friendly tool to assist with that? I was thinking even about using a wood filler, but I guess it would be too much at the top where the difference is 10mm, but maybe at the bottom where there is little difference it would work? I hope the pictures help getting a better idea? Thanks! https://imgur.com/a/SP29XIm