Jeremy Harris

Seems possible. I think I'll buy another one to take apart and see if I can reverse engineer it. If it does use thermistors, then spoofing the resistance would seem to be the easy way to bodge it. What would be neater would be to find that the JTAG port is still on the board, that the reprogramming fuse has not been blown and that the code can be reversed engineered to change the 7 deg setting,

The thing that makes me very slightly uncomfortable is that all the products ESP sell are manufactured by other companies (in the proper sense that none of the component parts are made by ESP themselves). There's nothing wrong with this, Navitron have been reselling very thinly disguised Chinese products for many years now, and even the big players subcontract out some component supply, and assembly to China. Initially, at least, ESP were just exporting Chinese stuff, chucking their stick label on it, and selling it at a higher price. This is not supposition, I was told this, face to face, by an ESP employee a few years go, when I showed him some photos of Chinese products that seemed identical. Since then, ESP, have been at pains to stress the work they do to get these units manufactured to UK specs. However, both I, and a custom bike builder friend, have fallen foul of some quality issues. My bike building friend now employs a UK agent in China to stop this, as it's a cultural thing; price take absolute precedence over quality and reliability, unless someone is there to stop it. The basics of the 15 kW ASHP here is that it sees to use either a Copeland or EVI scroll compressor (OK, but a million miles away from being a "Rolls Royce") plus a load of off-the-shelf components, that do a reasonable job for the price. Does the real-life performance match the claims? Who knows. Based on previous claims, and known energy performance, I suspect not, but it's up to each person to make their own conclusion as to whether to spend a few hundred more on electricity bills or have the peace of mind of lower energy use and guaranteed very long term support.

We used Doordeals oak veneered doors and solid oak facings, architrave, skirting and stairs, and used brushed Osmo oil every where. Pretty quick to do, but a fair bit of effort needed to get the oil worked in to every crevice. The process we used was to rub every bit of timber down, along the grain, with a green (coarse) Scotchbrite pad. The timber was then wiped over with a barely damp clean rag, wetted with white spirit. The Osmo oil was then applied neat, with no thinning, and brushed in well. As above, it took around 20 minutes per coat (less for me, more for SWMB). I laid newspaper under the door gaps to catch any drips. Before subsequent coats the timber was rubbed down lightly with a clean Scotchbrite pad, to de-nib the surface. The doors got two coats (they were going to get three, but two seemed plenty) and the stairs got three coats. We used the satin finish Osmo and spent some time with the (Purple) Scotchbrite pads rubbing with the grain on all finished surfaces that were to be touched (banisters etc). This has given a very smooth and hard wearing surface, and I'm frankly amazed at how well the stairs have stood up to what's been a lot of traffic. When they have got a bit scruffy, I've wiped them down with a rag and white spirit, used a green Scotchbrite to remove any marks, then given then another coat, and they come up like new, every time. I do have a tin of the tougher Polyx here, but have yet to try it. I was thinking of using it on the stair treads, unless someone says otherwise. Osmo oil may seem expensive, but it does go along way and needs very little time to apply, so I thing that, in the long run, it's probably pretty good value.

We can probably help a lot more as details become clearer, as we've all been there, done that, in one form or another, and have the scars to prove it! One thing is for sure, and that is that a self build, renovation or conversion project like this can be very demanding on your time, and sadly I would have to say that it pays to treat "experts" with a certain amount of caution. There are some very good people out there, but there are, unfortunately, a very large number of monkeys, who have near-zero skill and will try and charge you the earth. My advice would be to consult here as widely as you can, sift through the differing opinions, and use this information when seeking contractors. The more knowledge you have, or can acquire, the less likely you are to find yourself getting ripped of.

Unfortunately Salus are keeping things really close to their chest, with very little technical detail about how these work, or even what sort of hysteresis the temperature setting had. From a very brief play around it seems that the drive mechanism is a geared motor that drives both a threaded rod that drives the actuator pin, and winds up a spring to allow the power off close. The two clip on sensors seem to be thermistors, I think, and it doesn't matter which is the hot one and which is the cold one, the system just maintains a nominal 7 deg C between the two, if it can. In my case it seemed to be maintaining about 6 deg C very well, so there could be a bit of a tolerance. The case does look like it will unclip, so I'm tempted to order a spare and take it apart, to see if it can be reverse engineered. The information from Salus is so poor that it doesn't even tell you that there is an LED that shines through the case and which stays on when the valve is actively motoring, or flashes when it is adjusting the temperature. The latter process is does in stages. It seems that the valve moves the pin a bit, waits for a minute of two to see what has happened, then moves the pin a bit more, until after a few minutes it has set the pin at the right place to maintain the set temperature differential. The ability to set this differential on the outside of the unit, using a small adjustment pot, would make this unit very versatile indeed. As it stands, used as I'm using it, as an entire manifold temperature control regulator, it is pretty close to perfect for our house. I could use maybe 1 deg C lower in the temperature differential, to get rid of a bit of the residual overshoot, but there may be ways I can do that by repositioning the sensors. Right now I have them just clipped to the nearest flow and return pipes, but they are long enough that I could strap one to the ASHP flow pipe, where it would see a slightly higher temperature. It would need a new clip, as the supplied clips are designed for 16mm pipe, but the sensor just slides out of the clip and could, I'm sure, be made to fit a standard pipe clip. It would be nice if Salus released more information on these units, as they seem to be potentially far more useful than the limited information about them might suggest.

Just fitted this Salus auto balancing valve, but fitted in a slightly unusual way, as all our loops are run as a single circuit. I fitted it in place of the normally closed thermal actuator valve that was on the return end of the manifold, not as one of the loop control valves as Salus intend it to be used. It was a direct replacement for the existing normally closed thermal head, so was easy to fit. It comes with two clip on temperature sensors (not marked - either can be flow or return) and if these are fitted it will try and maintain a 7 deg C temperature differential across them, whether heating or cooling, it seems. At first I just left these dangling, fitted the valve, wired it up and tried it out. It's much faster than the thermal actuators, and uses about 1/4 of the power. The actuator takes less than 30 seconds to motor from fully closed to fully open, and seems to close using a wound spring, as with the power off the gears can be heard winding the pin down to close the valve. There's no hammer or any adverse effects at all, the UFH just comes on a great deal faster (the old thermal actuator was taking around 8 minutes to open fully). As this device tries to maintain a 7 deg differential between the two remote clip on temperature sensors, I tried it out, with the sensors clipped to the nearest to flow and return pipes. Our floor was at around 19.9 deg C, and the flow on the mixer was initially set to 25 deg C (it's usually between 25 and 26 deg C, about as low as it will go). All worked OK, so I then opened up the mixer valve so that it was letting in a flow temperature of around 38 to 40 deg C, straight from the ASHP. This is where things got interesting, as the Salus valve on the return motored a few times, then set the manifold flow temperature at a very steady 26 deg C! Normally, with the mixer valve wide open I'd easily see the manifold get up very close to the ASHp flow temperature. So, the bottom line is that this new valve not only turns the UFH on and off a great deal faster, but it also does the job of the mixer valve as well, IF it's fitted where ours is, as the return valve on the end of the manifold. This seems like a very neat solution to me, as it does away with the need for a thermostatic mixer valve - right now I'm leaving mine set on maximum, but I may remove the remote sensing head and just fit a blanking cap to hold that valve wide open. I didn't anticipate being able to get such good control with this valve, although I'm not at all sure that Salus envisioned anyone would use one like this! Thanks @Nickfromwales for the head-up on these valves.

The tree nursery that we're using has some pretty large trees available, depending on how much you want to pay. Typically 2.1 to 2.4m high Copper Beach trees are around £35. Larger trees, like the 4.2 to 4.4 m high Western Red Cedar are a fair bit more expensive, at around £145. Large (4m +) holly trees (not bushes) start at around "£200 or so, and you need two, male and female, for most species, in order to get berries, the exception being Ilex J C Van Tol, which is self-fertile, so always has berries. One thing I learned the hard way is that bare root plants will often stay dormant through the first year after planting - ours did, then took off the following year. The root balled planst took off straight away, so I would suggest going for root balled, or perhaps pot grown, for "instant" effect.

Allowing for the fact that your house is double the size of ours,, that RHI figure implies a heating and DHW requirement is still nearly 3 times higher per unit floor area than ours, so why is that? Our RHI worked out at less than £80 a year, IIRC, payable for 7 years, and that didn't come close to covering the additional cost incurred by having an MCS approved installation.

Thanks @PeterW, that's pretty much what the chap at the tree nursery said, I was just a bit cautious when I read how high these can grow, plus having had a nasty experience with Leylandii!

Looks very much like one of several units being sold on Alibaba. A search for 15kW heat pump on there will pull up quite a few that look very similar indeed, even down to having the same type of scroll compressor, inverter drive and stainless case. I suspect that ESP are, as has been the case in the past, sourcing units from China and then making sure they are suitably approved for use in the UK.

No thanks, I found a local branch of Medlocks and called them. They were pretty helpful, but could only supply the special (expensive) any-tamper screws, but not the standard posi-head screws that the thing came with. For now I reckon that the combination of the spire clips and stainless self tappers will do the job, I think.

Yes, but I think I have a bodge. I've dug out some spire clips, plus some large head stainless self tappers, so with a bit if luck i can fit the spire slips to the case and get the self tappers to hold the lid on. I doesn't need to be waterproof, as it's screwed to the wall in the workshop.

I was do some minor mods to the heating/cooling control system today, and noticed that the heating hadn't yet come on at all this year, despite the sub-zero temperature last night. I made the small modifications (really aimed at stopping a motorised valve from operating every time the programmer turned on, whether the house needed heating or not) and as a test I manually turned the UFH heating on for half an hour, just to check all was OK and that the buffer tank valve was now just staying open all the time, unless there was a cooling demand. The house was up over 22 deg C within half an hour, and I was getting a bit warm laying carpet tiles in our "loft" storage areas (which are under the eaves) so had to run down and turn it off. The house was still over 22 deg C when I left at around 17:30, so will undoubtedly be a bit warm for the next day or two....................

That's what we don't want! Most of the trees we've chosen will either never grow very tall, or are slow growing and easily shaped. The one that worries me is the Thuja Plicata - Western Red Cedar. The tree place reckon it can be trimmed and kept in shape to maintain it at the 4 to 4.5m height we need, but I'm not so sure. I've little experience of this particular tree, but a lot of experience (all negative) with the thug called Leylandii................... I'm tempted to swap it out for a fairly mature Holm Oak, the evergreen one, as I know that can be kept trimmed to a nice looking shape.

400mm spacing does make for a very stiff and solid structure. I'm really impressed with the lack of any detectable bounce in our floor, which is Posijoists on 400mm centres.

Ours is 400mm everywhere, walls, joists and rafters.

If she buys the supplies, you cannot reclaim the VAT, so make sure that the orders are made by, and paid for, by you. If a receipt has her name on it HMRC won't refund you the VAT.

We've finally got around to ordering trees, along with a great deal of help from the local tree nursery (Landford Trees - highly recommended). We're planting two cherry trees either side of the entrance gate, Prunus Shogetsu, then a Himalyan Birch (Betula utilis jacquemontii), then a mixed row of Craeagus Pauls Scarlet, Sorbus Lutecens, two large Ilex Nellie R stevens as primary screening. Finally, towards the end there will be a Fagus Atropurpurea, and possibly a Thuja Plicata, The latter is the only one that causes me some concern. We will be buying mature (~4m high) specimens of the key screening trees, and the nursery had advised that we can maninatin the conical shape of the Thuja Plicata by regular and careful pruning. This isn't a problem, as we like the look of the tree, my question is whether or not we can keep this treee looking tidy. I have adverse experiences of trying to keep Leylandii in check , and this makes me wonder whether or not it's practical to keep a Thuja in shape or not.

I've ordered one, and will see how it behaves. It will only operate against a closed circuit in cooling mode, as in heating mode the buffer tank motorised ball valve is always open. so if there is a hammer problem it will only be in cooling mode, and and I think we can live with that for the few time a year that it operates. After we've planted the trees over the next few months the cooling mode may well not come on as much, either.

Brilliant Nick, exactly what I was after, With luck the bypass relief valve should remove any hammer issues. The odd thing is that I knew that there were stepper motor actuators, as the diverter valve failed in our Vaillant and that had a linear stepper motor drive, I just couldn't find an actuator for a standard valve head.

This won't work, I'm afraid. To reclaim VAT you, personally, have to buy the goods or materials, in your name, and using your card, cash or whatever. HMRC will not allow you to reclaim VAT from goods and materials purchased by another. That person has to be VAT registered and and then supplies goods and services to you at zero rate.

Cracking job, Russell, and I think it does make the point that the proposed new development looks much neater and in keeping with the setting. I'd be surprised if these models don't have a positive impact at the planning meeting. Blame me of they don't..............

Currently I have have a standard (22mmm thread?) 230 VAC thermal actuator that turns on or off the return from the UFH manifold, as a part of the heating /cooling comtrol system. This actuator is a NC one, that opens when 230 VAC is applied. We have a minor problem in that when there is a call for heating or cooling there is a delay before this valve opens. This doesn't matter in heating mode, as the ASHP can unload into the buffer tank, but in cooling mode the only load is the UFH, and because the UFH valve takes 8 minutes to open, it means that the pressure bypass valve opens, and the ASHP shuts down for a few minutes. What I'm looking for is a faster Thermal actuator, that will be a direct replacement for the 230 VAC NC unit, but that will open a lot faster. The temptation is to drain the system and install a fast acting 12V motorised ball valve, as is fitted to the buffer tank, but that means draining and refilling the system.

My experience is that terminating sockets is dead easy. Terminating plugs needs a lot more work, and ready made patch leads are dirt cheap, so it's only worth making custom plug-terminated leads when you really have to. I've made a few custom patch leads where I've had no choice,, like the PoE injection lead for our modem, but would rather just buy them as needed. So, my advice is to terminate all your fixed wiring at fixed sockets, be they on the walls in rooms, or on a patch panel, and then just buy a few patch leads. There might be a very small cost penalty in buying patch leads, but offset against the added cost of a plug crimp tool, plus the time it takes to make patch leads, it's really not worth the hassle.

The same way as they connect to the wall sockets, usually.