Nickfromwales

Im on the research, so will update again shortly as im due to do @AndyT's head in again on Monday with my 3rd round of "and what if I do it this way?" questionnaires.

I think it'll be fixed before that !!

I draw the line on having to have to catch it then eat it. In Scotland there must be a McDonalds ?

I could slum it I suppose. Do they have bacon where you live ?

I think if there were any ZV's we'd have seen them by now tbh.

Out of the mouths of babes..... Half chocolate coated malted milks, obviously.

@Onoff Just being mindful that this circuit is feeding 22mm flow and return through the house going to 4 x UFH manifolds.

Yup. leave that deal with the c-curve of the pump rather than the not great relays on the HM PCB's. Cheaper and easier to replace the ZV head too.

Too restrictive. the ZV will open to give full bore. Plus you dont really know which way the convection would 'pull'

The hozelock rig is usually supplied with the solar system as you never top up via cold mains through a filling loop. Instead you make up the solution, pour it into that bottle, connect to the fill point ( which has a non-return valve so juice can only go in ), and then you pump away until the pressure is topped back up accordingly.

Ah, the million dollar question. A summary is difficult as there is probably a bit more there thats "Donald Ducked" than we know about. For one, a pump thats close to 100oC is obviously just burning / burnt out and needs changing, and given locality, the sensible thing to do would be to change all the pumps and their isolation valves whilst the system is drained. The alterations as per 'chapter two' will need implementing, but after speaking with @PeterW earlier today, a new PHE is not mega bucks, even for for a whopper. I still maintain that if the manufacturer says its ok that we hook the boiler up direct to the TS, so doing away with the PHE, PHE pump, and the need to pressurise the boiler periodically. As the boiler is a 'system' boiler, not a 'heat only' boiler, it has an integral pump so the flow to / from the boiler / TS is sorted. Lets simplify where we can. @PeterW seems to be on the HM system like a tramp on a kebab and reckons it can be made to work with whats there, so thats just down to being there with a multi-meter and a fresh brain. TS / boiler/ time-clocks / associated control wiring just needs redoing, fresh, from scratch. Refitting what kit is already there should suffice. Adding the 2x 2-port zone valves to the summer / winter boiler return would still be my chosen route. Add a 2-port Zone valve to the UFH flow to stave off convection heat loss when the heating isn't being used. That should stop the TS going cool during the 2-hour no-E2000 times, and any other time the space heating isn't required. That would also provide the heating 'kill' that I earlier referred to. Adding a pump and blending valve to each manifold is a no brainer, hopefully theres 230v at each manifold wiring centre. Fitting of a large magnetic filter on the boiler return ( as low as it could go ) would be of benefit, but id probably put one on the UFH flow too to cover what won't get picked up by the boiler filter. The only remaining TMV should be the DHW one, so prob change that too for the sake of £50. Other TMV's would be the new ones at each manifold. Flush and chemical treatment as required. Flush the ST with that 6.5bar mains and fill it back up with antifreeze solution and get the bugger working again. Program the heating controls accordingly and demonstrate. Piece of cake. Thats the remit for the works required, plus whatever comes out of the wood ( pipe ) work when your there.

To me yes I just hope my minions can keep up

@newhome Get the stuff assessed and get it turned into heating dollars. The stuff will be of value to those who want it, and tbh on eBay you could sell a bucket of piss in minutes. Do you have paperwork for the simulator?

@JSHarris. Would the glycol / other turn to jelly? I've not seen that before. There is a top up point which shows the ST system can be repressuirsied with ease, just needs the hozelock pressured pump up bottle and some more so,union made up and it may come back to life by itself. I can't remember how these panels get bled of air. Do they usually have automatic air vents at the top of the solar collectors or is it a manual job?

Chapter two The reason ive been silent this eve is that ive been studying this beast so I can answer more definitively. 'Tis a mysterious device of many guises.... If you really dig into the MI's ( manufacturers installation instructions ), ALL of them, it gives addendum's for the various configurations and alterations which you should be making according to heat source / space heating etc. So.... For starters we know that the cylinder stats do zilch, thanks to cock guy, so the above statement is right, but for the wrong reasons. The TS has 3 cylinder stats which I thought I understood, but I got a bum steer off their own tech guys so I went it alone instead, finding out why and where and how many there should actually be. So.... The lowest stat should be used to control a heat dump which basically brings on the space heating pump if the TS ever gets to too high a temp, so prob set to around 70oC. The middle stat "can" be used in tandem with the upper stat for 'buffering' heat into the TS. The top would be boiler on, and the bottom would be boiler off. Thats iirc supposed to give longer burn times so maybe better suited to pellet or oil. Not suited to this setup, with electricity and off peak in the picture so we move on... Middle stat should be 'full heat' aka winter mode, and the upper stat should be 'partial heat' aka summer mode / hot water only. These are more commonly seen / understood as 'hot water' or 'heating and hot water' on conventional controllers with say gas boilers with hot water cylinders. The MI's also state that you can locate these stats in different places by moving the stat pockets around according to the end application, so again its a problem as this has clearly been fully loaded to deal with a wood burning stove / solid fuel heat source in the picture, which it was never intended to have. Exactly what its supposed to do, when in hot water / summer mode. Just enough DHW to fill a bath or have 2 showers etc according to the MI's. Space heating cannot be drawn when in summer mode, so the controller that selects that must purposely kill the space heating too. The cylinder stats control the boiler and nothing else. Simple. You select 'summer mode' bringing the system out of 'holiday mode' aka 'standby', and then the upper cylinder stat calls for the boiler to heat the TS upper portion until satisfied. Bingo bingo. Likewise with the middle stat, for 'winter mode', but with the full heat. Bingo bango2. Selecting winter mode will also then lift the kill on the space heating and if there are any rooms stats wanting heat, the relevant pump/s will turn on, as commanded by the wiring centres, and heat will be drawn from the TS as its being injected by the boiler. Eventually the boiler will catch up with / match demand, eg the rooms get up to temp and start sending warmer water back to the TS return, and the TS will eventually satisfy the middle stat and the boiler will go off until the stat next calls for heat. Good news is the boiler will start to modulate as the need for heat is reduced. The next thing is how to get the heat into the TS. The flow into the TS is direct from the boiler PHE, but the return is via a TMV with connections to the mid/upper, ( for super fast heating of the upper section in summer mode as thats where DHW sucks heat from ), and then when the upper section is warmed sufficiently the blending valve then starts drawing cool water from the bottom of the TS so as to blend down the return temperature. Pay attention, this is the important bit. That blending valve is there to keep the return temp to the boiler at around 50-55oC to make the most of a condensing gas boiler. We dont have one here so another over-complicated trinket for the bin IMO. The boiler return should be only connected to the lower return tapping, and the other one that that TMV is connected to should be capped off. Note that the lower return tapping should be above the ST coil to maximise ST input. The ST coil is right at the bottom BTW as its likely to be, on average, the lowest heating input medium so is of best use when injected into the coldest part of the TS. They got that bit right. Or........the posh 'NFW' option..... The return tappings ( upper and lower ) could be via 2-port zone valves. The upper one opened by summer mode, and the lower one opened by winter mode. IMO what they should have offered in the factory for a non gas boiler installation. That ensures that the TS is using the minimum amount of energy in summer mode. For winter mode, even if no space heating is calling for heat so just the boiler and TS cycling, the lower cylinder stat will always try to fully charge the TS from tip to toe, so you will then have stored energy for the 2 hour no-E2000 input times. The PHE needs to go, as it think its cream knackered anyway. As we've had mention of the boiler circuit being full of crud its safe to assume that crud has become lodged in the narrow water-ways of the PHE, thus reducing massively its ability to transfer heat fro the boiler to the TS. I will speak to the boiler manufacturer tomorrow, if they pick up, to see if it can be converted to run on the open pipe gravity feed from the TS F&E tank, as that would mean we could do away with the PHE and additional pump altogether. It would hopefully just involve bridging the low pressure switch so the boiler ignores the low ( prob ~0.8 bar ) that it'll see if the F&E is high upstairs. Im assuming the F&E tank is upstairs as the 1st floor UFH is connected to the same body of water. That would get heat from the boiler screaming into the TS with nothing in the way and should massively decrease the reheat ( aka recovery ) times. After all that bollocks, we should be simpler, faster, way more efficient and have cut a good bit of chaff away from the wheat. You cant do that as the pellet flow goes in too low. In summer mode the flow MUST go in at the top where the DHW PHE feed is drawn from, otherwise your over-heating the TS in summer just to get DHW. On electric its important to make this as efficient as possible. The rest is just down to wiring and commissioning. A LOT to do with that as I find its just usually better to pull all the wiring completely off, put the radio on, and rewire the thing from scratch. Fault finding and working out what cock did would take longer than rewiring it. Enjoy!

Plus the A38 goes hard in around 45 mins too, so beware.

The A38 I only bought because I needed to be tiling in a couple of days. If you dont need that, ahem, level of urgency ( ) then just cement it.

Pm's are being exchanged

I quoted for two 17kw ASHP's to supply space heating and DHW uplift for a converted primary school and it was less than low energy.

BCO wouldn't be happy with a foul T and no access

How many room stats? eg how many individually controllable heating 'sections' / rooms.

@newhome Are you ok to get things running as it was for tonight?

100%

If one pair of 22mm flow and return pipes, travelling through a TMV, and circulated by one single half dead pump, no bloody wonder lol. Each UFH manifold should have its own pump so there is the full potential of a dedicated pump to force the water in the ufh loops around, and they should do nowt else. The pump at the TS and the TMV that services it should only be circulating the heated water PAST the manifolds and the manifolds should just be drawing whatever heat they require at any one given time, eg when the floors are up to temp there is only a little heat required. Im pretty much sewn up here tbh, as I now know what needs doing to sort this mess out.......just got to find a way of breaking it to you gently. Go get some more voddy.

And rewiring squire