Nickfromwales

Running the HRC pump is pennies. Less P/A than feeding, say, a lake full of carp for example. Providing the hot water to send around the pipes; "free" when the PV is on and burning, cheap enough also when the ASHP has to reheat it, eg during winter etc, especially when you can get electricity as cheap as 5-6p/kWh and strategize when you heat the water fully ( eg at night on Octopus Go! ) and THEN put that through an ASHP and possibly halve that again to 3p/kWh. Can't please everyone eh? ?‍♂️ People cry about spending pennies, by comparison, after saving a LOT of money doing as much of the work themselves as they could / can. Some are more skilled / adept than others so save much more than most, and those folk need not sit around weeping about parting with a hundred or so bucks a year ( IMHO ). They probably spend more money a year, say, on throwing expensive crockery about........but that's just a wild guess of course . This is a bit like fitting lots of lights in your house, and then moaning about how much electricity it costs to switch them on. A bit like why most never own an american V8 gas-guzzler, but instead go get a Prius and drive it downhill only, only on windy days, with only if the wind is behind it....? , probably. On a serious note; A cheaper way of getting hot water to the most remote parts of the property would probably be to run a 1000m long hose pipe through the local village, with a sign attached to it saying "rub this pipe for luck" and then use the heat energy from the friction to offset the £100 a year costs of running the HRC. You know what, that's a Dragon's Den opportunity if I've ever heard one. Nobody nick that idea until I get back, ok. I mean it!!

Steam dissipates with a reduction in temperature. This is dependant on the size of the room as much as the rate of extraction.

Destroying the new EV.

The secondary PRedV and single check need to be fitted immediately. They’re not optional !

Not if they’re heating pipes. Insulation every single time.

You can dump that into a high temp pump in an empty F&E tank.

Sleeves for the hot and cold is minimum, but the heating will need to be wrapped with insulation to go through the masonry, not just sleeves. 22mm + 18mm ( 9mm wall Armorflex insulation ) will need 40mm holes for flow and return. Ideally you should be insulating the hot and cold too if under a ventilated suspended floor space. I would just knock a whole brick out and then foam around the pipes after you’ve run them through to close the gaps completely.

There is a VERY strict rule about not having any type of valve / control between the cylinder and the EV. The PRedV does have throughput but it’s only the balanced draw point or body of the control group that fully satisfies that requirement. If you look at a few manufacturers installation instructions you’ll see the recommended connection points / detailed criteria. A quick google would have told / shown your guy this info for free. Bottom line is, it needs to be connected to the blanked off outlet on the control group. It can’t stay where it is. ? Doesn’t come in to it I’m afraid. UVC’s and G3 need to follow the manufacturers installation instructions strictly, and all you can do is add to that. You cannot move things around to try and beat the problem, as that will lead to further failures / compromises. Bigger question; have you not yet fitted the secondary PRedV and single check non return as per my earlier replies?

The T is before the PRedV is incorrect. The effort they went into chopping pipe and adding the T was a waste of time and money, as the correct position would have been the blanked off / already available 22mm balanced draw off union seen on the “control group” aka multi-block. I will concede that the retro-fit of the EV is a better / longer term solution, but ONLY if the pre-charge pressure is tested and checked every year during the annual G3 service & inspection. The 7 bar T&PRedV is fine, as it’s downstream of the 6 bar cold mains relief. In honesty, the sooner that ever opened the better.

So with that and the plasterboard channelled you you’d have 56mm to play with? More if it’s plastered plasterboard.

Remember to not use a single screw in the middle of the timber, instead go 1/3 down and 1/3 up with 2 screws per position so the timber gets uniformly pulled together and the glue fully ejected / displaced.

You may find that strangles the flow rate. Not something you'd want with 18 flats off it

Sky for the new one it is then lol.

That's the intention with the design of those screws, to pull the two pieces of timber together and for the head of the screw to not countersink itself, hence the large flange type screw head. The type of metal used also resists snapping, like you get with long woodscrews. I used 6.0 x 150mm Velocity screws to secure the ridge beam of my gazebo down, and most of them have snapped where the blank shank meets the start of the threaded section. I changed to hex drive timber-lock screws and they're way better. Heads are too small on both for what you're doing, hence the need to jump to construction screws.

..as in factory fitted. They are directly connected to the UVC by the plumber as the first thing off the UVC, if you're not going manifold / twin TMV ( one for the house and one for just the bath(s)) setup etc. You can mount them anywhere, but for max efficiency you keep them as close to the hot water outlet as possible to reduce losses.

If you’re selling the house with VM then migrate that with you. Fit SKY in the sale property and job done. ?

Nope. It’s either got an EV screwed to the top of the cylinder, and the external factory case of the UVC extends up to hide it, or it’s a bubble top where the hot pipe is extended down from the top to allow a pocket of air to be trapped to use as expansion. If the bubble top has depleted, you simply drain the UVC and refill to replenish the bubble or it’s the other type and the dead EV needs to be replaced immediately. If you leave the ruptured factory EV in service you’ll eventually have a full and catastrophic failure and a flooded house to boot. The internal steel body of the EV ( if it’s not the bubble top gone ) rusts away day by day, exacerbated by the constant heat and influx of fresh oxygenated water, and perforated. At that stage the cold mains pressure is free to escape and flood your house. For good measure, that usually blows whilst you are out of the house and the cold mains is constant so it keeps pouring out until you arrive home……. It doesn’t sound like your plumber is very experienced in UVC installs / repair I’m afraid. He may be a good general plumber, but this is a terribly dangerous scenario if the factory EV has failed, or a bloody expensive unnecessary repair if it’s just the bubble that needed regenerating. Have a look to see if the lid of the UVC comes off, easily, and you’ll have your answer.

@SillyBilly These

Explain more please. Baffle? Where?

Your BCO joins the others which talk from yesteryear in a lot of instances. G3 requirement kicks in with all UVC installs, and every single UVC I’ve ever fitted ( over the last 20 years ) came with a supplied thermostatic mixer valve aka TMV. You set that to 50oC and job done. If it’s a new plumb install then add a second TMV in parallel and set to 46oC and run that to the bath hot supply, or just fit a thermostatic bath mixer tap which is easier. Also nice to have a thermostatic bath mixer tap if hair-wash on a handset is required at the bath. What is the proposed method of carrying out the pasteurisation cycle? ASHP to power up an immersion?

?

You’re not really supposed to run 32 or 40mm more than 3m in normal circumstances, but when adversity strikes you can mitigate against ‘risks’ as per the above ( 50mm pipe and plenty of cleaning access etc ). Theres no way in hell that you can go to 32mm pipe for this, and I wouldn’t do it in 40 for more than 6m before upsizing to 50. What’s the issue with locating the 50 all the way?

It’s that compromise or a pump Take the compromise ! +1 Forget the above mention of 110mm pipe, and just run it in 50mm all the way with T’s and cleaning ( rodding ) eyes at each significant point or change of direction instead of bends. All bends need to be bends NOT elbows eg swept. 23m will be fine.

Plenty good enough

I prefer resin glued and construction screws just short of the width of 2 timbers / layers. Fix 2 together, flying and clamping and working from one end to the other so you can manipulate the timbers with additional clamps as you work along the length, then add the 3rd timber repeating the same method. The construction screws allow the timbers to be pulled together incredibly tightly, thus ejecting the excess of the resin glue, plus, combined with the info below, you should be able to marry the timbers to pull each other back to a straight pair, if so necessary. Examine the timbers for the ‘cup’ lengthways and sidewards and laminate them strategically to get the best overall uniformity. The lengthways cup should be strictly observed in any installation / scenario with the natural ‘deflection’ ( cup ) sent upwards so the cup naturally straightens out upon own weight and subsequent bearing of loads from above post installation.