ProDave

The thing that puts me of oil, is the huge volatility in price. In the time we were using it, it went from about 25p per litre to over 70, it's lower than that now, but it varied a lot more than electricity. If you do go for that, get a tank large enough for a year or more, most years it is cheaper in the summer, August us usually about the lowest. Bulk LPG, unlike oil, ties you to that supplier, but bottled LPG is very expensive. We use bottled for cooking and a 47Kg bottle lasts over a year so not so bad. Don't discount solid fuel for heating, even dare I say it a wood pellet boiler and claim the RHI?

Yes I am very much in the accidental / reluctant landlord category. I really hope things will pan out as planned and that will come to an end within a year. At least it's only 50 yards down the road when maintenance is needed and to be honest not that much has gone wrong.

Another problem at the old house, heating tripping, Quick diagnosis showed the central heating circulating pump was faulty. I had a spare pump so it will be a simple 5 minute swap, WRONG. It has what I regard as normal pump valves, a bit like this https://www.screwfix.com/p/ball-pump-valve-22mm-x-1/51338 As soon as I started to turn the screwhead to shut off the valves, water starts squirting out from both of them. Good job screweys were open so got 2 more to replace them and it was a bigger job, partial draindown etc. I nearly paid the extra to get the "better" pegler ones, until I read a review warning that the thread on the pipe side was a finer pitch so you could not just swap it and use the old nut and olive. that would have made it an even bigger job to change. So probably next time the pump fails they will again be totally useless as an isolation valve.

I would look at roofing the whole thing in a monopitch roof to get the maximum area south facing. The small triangles you describe are too small for much in the way of panels.The "flat" bit is more promising but would be better if is sloped to the south rather than being flat. The way a normal system works is you have a consumer unit in your building. That will have a light and socket circuit for the normal stuff. You then have another circuit for the inverter. A Grid tied inverter generates power synchronised to the mains frequency. Such power generated will power anything in your home and so reduce your electrcity bill. Even if your heating in the summerhouse is not on, something somewhere in the house will probably use it. If reduced running costs is your objective, is looking at the summerhouse roof tacking it the wrong way? Would you be better putting a larger bank of panels on the house roof?

The point is I can't measure flow. My hole and "height of fountain" is a crude measure of pressure, but not flow. Thinking about it more, if I did get a big fountain at the top that would be a sign of a blockage in the field, but I don't get high pressure there, so it must be flowing freely into the soakaway? There won't be plough damage in our garden, and I am 100% certain the entire soakaway is well below plough level.

Apart from the garden hose (reverse the fitting I made) I can't see an easy way. The only other bit of pipe I have is a bit of 25mm mdpe, but I don't like the idea of piping grey septic tank effluent down it, I would rather keep it clean in case I want to use it for potable water.

Could that mean they don't have the reverse cycle defrost function, so they would indeed be useless for winter heating?

Okay the test results are in. And they are inconclusive. I need some help to check my thought process: With the mains water connected via the garden hose and my bodged set of plumbing fittings. I get exactly the same, just a trickle from the top test hole. (the bottom one is now plugged and holding). But go in the house and you can hear a good flow of water exiting the outside tap. So I am beginning to wonder if I am barking up the wrong tree and there is no blockage. The point I have drilled the top test hole is almost certainly the highest point the pipe gets to, from there is is a gentle downhill run to the soakaway in the field that can't be more than a few metres away. There it opens up to 4 runs of 110mm perforated pipe where it will drain freely. So even if things are flowing properly, there won't be much pressure in the pipe at that point will there, so would I expect more than just a trickle from a small hole drilled in the top of the pipe? I came to the conclusion originally that there must be a blockage because after 10 minutes of pumping with the new pump, the level had not gone down noticably. I am now veering to the other theory that this is just a rubbish pump and barely able to achieve a significant flow at that head. I am minded to sport £200 on the Italian pump before doing any more.

I suspect because they have a large volume of water to heat, they are "all or nothing" heaters so probably direct on line start no inverters, no ability to modulate to low power. Not a good idea for a house heating system.

Cutting it is a last resort. I can't keep reiterating just how big and stiff 50mm mdpe is. In order to pull the pipe apart enough to insert an mdpe coupler I think you are going to want quite a length of pipe uncovered to be able to bend it enough. I will post back how tomorrows flush attempt goes.

I used 2 63mm ducts to all my vents.

Can you relocate the plenum boxes to the other side of the steel so only 2 large pipes have to pass through that?

I have scoured my various boxes of plumbing fittings and come up with a collection of fittings that will get me from my female BSP to 15mm copper, with a bit of stretching and a jubilee clip the hose should go on that. At the other end the hose fits properly to the outside tap at full mains pressure. I will give that a go tomorrow and see if I can flush this thing through. Using my hole in my top pipe as a guide. I will be happy if I can get a fountain spurting from that.

Well the easiest way would be 1 1/2" BSP female to a fitting a standard hose will go onto. Any ideas?

Yes it does. Currently paying just over 14p per unit and 20p per day with Octopus

Just had a look. They quoted me 31.74p daily charge, day rate 21.56p night rate 14.71p I pay less than their day rate and a lower daily charge for a single rate supply,

I am more tempted now to try just buying one of the original Italian pumps as was supplied with the pump chamber when new. Not quite as expensive if you buy direct from Italy https://www.ebay.co.uk/itm/POMPA-SOMMERSA-EBARA-RIGHT-100-MA/264139492924?hash=item3d7ff0ce3c:g:ufwAAOSwBZBcPYFh:rk:2:pf:0 These people offer to beat any genuine on line quote so I have contacted them to see if they will beat that ebay offer https://www.prestigepumps.co.uk/manufacturers/ebara-pumps/?gclid=EAIaIQobChMI7O36i_zA4AIV1IXVCh2ffAvKEAEYASAAEgIDivD_BwE

Whatever we do is going to be some serious hard work just to get at one end or the other of the pipe. The top end is really a non starter, that means digging deep in the now ploughed field, definitely a job for a digger not by hand. The bottom end as I say needs digging back far enough to be able to to bend the mdpe just to pull it back out of the fitting. The only realistic hope of getting a mains hose to this system is to try and make a connection to the short "flexible" hose that the pump connects to. At the top end it is a quick release fitting that came with the tank, and at the bottom it's 1 1/2" BSP This has to be a lesson for all those that can avoid it, how utterly crap pumped outlet systems are. I am SO glad the new house does not have a system like this, and so glad we did not end up with the original plan of a umped outlet to a filter mound,

The logistics of finding a set of fittings that will actually connect a domestic hose to any of the large bore fittings that the pump connects to seems very remote indeeed.

So an afternoon digging and can't locate the pipe at any other location, it has to be either not where I am expecting it, or a lot deeper than I am expecting. My memory fails me as to it's exact location and I have no other photographs. Re rodding from the bottom. Where the pipe connects into the pump chamber it goes into a 90 degree fitting. So to rid the pipe, we would have to dig back quite some distance to get enough of a "loop" of the 50mm mdpe to get it to pull back out of the fitting, so that is not a trivial exercise. When I turn the pump on, at the bottom, about 4 metres from the chamber, the fountain starts almost instantly. At the top it takes a few seconds for the dribble to start. When I drilled into the pipe in both cases the drill bit came out clean suggesting nothing other than water in the pipe i.e. no sludge or anything else. The water that comes out in both cases is clean. Now I have been pondering (clutching at straws) I am wondering if it is just a case the new pump is not powerful enough? This is pumping up hill about 2 metres, and the pump is down in the ground about 1.5 metres. The new pump is an identical one to the old one and is rated to pump up to a maximum of 8 metres. But what if this pump is sub standard or even faulty? Hard to prove that. This is a much cheaper pump that the original Italian pump, but a cheap one like this has worked previously But I am tempted to seek out one of the expensive Italian ones to try that? I had really wanted to do a third "hole" test at a mid point to draw a better conclusion. Oh how I wish I still had a digger. I do have another pump I might try tomorrow, it is not a new one but is my general purpose pump. Trying that might prove or disprove another point.

My inverter is IP65 rated but I put it inside the shed as that is a kinder (dry) environment for it.

Our house has no obvious large mass structure, but it certainly holds it's heat for a long time, and likewise takes a long tome to heat up. Probably the largest source of heat capacity is the plasterboard walls and ceilings, and the biscuit mix screed for the under floor heating. It is a very comfortable house to live in. you don't have to worry about when the heating is on or off, as the temperature will not drop noticeably for a long time when it goes off. Likewise the slow warm up from the low level UFH means it does not overshoot when the thermostats click off.

Okay results of the morning. located the mdpe pipe in the field margin before it enters the actual soakaway. Drilled a 4mm hole, turned the pump on and we only get the slightest dribble of water from that hole. Located the pipe closer to the pumping chamber, drilled a hole and when the pump is on we get a good fountain squirting 6ft in the air. So the blockage is somewhere in between. Having lunch now then back to digging more holes.

I suspect the blockage might have been building up for a while. I replaced the pump a year ago, and it has failed at 1 year. They used to last between 5 and 7 years before that. I doubt this years ploughing was the reason, then only did the perimiter run today and I am sure it had failed before then. I also doubt it was freezing. We always get a few weeks of really cold weather. It it had frozen, I am sure it would have thawed in the last weeks mild weather. and if it had split as a result of ice (unlikely for mdpe) there should be a split and a leak and some wet ground somewhere.

It has to be a blockage. The pump pumps at the bottom but there is no flow. I will let you know what tomorrows excavations find.