PeterW

Just to put a quick correction to this - the Arotherm 10kW split is actually an f-gas split so the backup heater is there to maintain heat in the water system to allow the gas reversal - there is no water in the outside unit … If they are fitting an Arotherm Plus 10kW then I’d be surprised if they aren’t just fitting the 40 litre wall mounted decoupler - it’s the same as the hydro unit inside today broadly on size, but doesn’t have all the heat exchanger for gas to water, and it doesn’t have the backup heater inside it. The backup heater is a 6kw separate unit but I do wonder if the reason this is not being specced is down to power issues or the need to run new cabling for it. nice thing on the new Arotherm plus is the flow temps will be 55°C or so which means warm rads ..!

Air separator probably piped up with a cold feed and a vent pipe - will be a gravity system no doubt that has been converted in the past and prone to sucking in air.

I would disagree there as some have heat loss that is so significant that the ASHP sizing becomes so large that a 3ph unit is required and the cost of running on electricity becomes prohibitive. I would seriously go backwards with this - 2 oven oil Aga is peanuts on Facebook marketplace, add an oil tank and go for permanent background warmth from October to April.. immersion in the hot water tank for the summer months and a cheap induction hob and air fryer for the months the Aga is off …

Also fill the tank with water as you go and concrete it in - you should roughly keep the levels the same as it stops stress in the sides. Depending on where it is installed - lawn or driveway - indicates whether you should cover with concrete or just gravel and topsoil.

Leave the washing machine out for scrap - someone will collect it. Old bathroom porcelain goes in the hardcore bin at the tip. Monitor goes to the electronics skip or area at the tip too

Sell - You’ll have CGT to consider at a later date too which really complicates things

@DevonBarn are you considering any sort of secondary heat such as stoves ..? If so, and also for the heating, I would start by putting UFH in as it can be used as a big heat store in the winter. I would also consider a very big heat “accumulator” setup with 1500-2000 litres of storage as you can run a boiler stove hard into it and then make the most of the hot water when you need it as either a buffer or a preheater for your hot water supply (which needs to be min 500 litre UVC) and then maximise your solar to divert into the tank too. It’s one of the only instances I would also look at Solar Thermal, as you can dump it into the buffer too. Like a lot of others say - start with a 3P connection though as it opens up opportunities ..!

You could use those and surface mount them on the inside and then countersink on the face for a small nut and washer - use decent epoxy filler and sand flat and it will create a strong hinge that won’t pull through as easy as screws. Other option is to make them a feature and get some brass plates made up to match the hole size and have brazed studs fitted to the back - using 3mm brass you would end up with a 15mm MDF sandwich but it wouldn’t be cheap.

Burn it off and continue to do so - won’t damage the tarmac but stop it before it can grow back and also occasionally flood the area with a weak glyphosate solution but bear in mind that it is neutralised in the soil in 48 hours

How ..? Y-Plan doesn’t distinguish between heating mode on the boiler as in mid position it is supplying both heating and hot water simultaneously. W plan can do that, but only with an opentherm ready boiler or using a boiler that can control the diverted valve. BG and others like Y-Plan as retrofit as it’s cheap and only needs the one valve and no pipe work changes. It’s a compromise especially if fitting a heat pump

old school design - you can put all the concrete on top of the insulation and put the UFH in that and creates one big storage heater. Just need to get your internal floor levels right from the outset

Flashing looks wrong - it’s on top of those Romans and the water will be tracking below the lead and down the chimney unless there is a very good set of soakers installed which is probably unlikely. Would also guess that render is letting in at the top - flashing needs to be cut in 35mm into the brick underneath and not just into the render. Ideally you want to cut back the render behind the lead too but doesn’t happen that often. Ideally that needs scaffold to work on it and the tiles removing either side and the lead replacing properly - possibly talking £5-600 depending on access

Replace the tap - 2 min job

JJ Crump cover your area - used them for a couple of jobs and they are good value.

I use the orange ones from Amazon - bit more expensive but they can last a good few hours and are much thicker Unigloves PRO.TECT Orange HD GA0054 Nitrile Single Use https://amzn.eu/d/b5BNSNI

Seriously over thinking this ..!! But ignoring the basics of fluid dynamics in that the fluid will flow through path of least resistance and you’ll have a hell of a job balancing this lot with no manifold pumps. I would fit a pair of Wilo Pico 25/1-6-130 on the manifolds and use self adjusting heads and then tune the flows to and from the LLH with the heat pump side pumps.

not that good if you have very high pressure even though it says good to 250psi. Better to put a 4 litre potable expansion vessel in and it will do the whole system.

what do you mean locking you out..? drop me a PM if it is still causing issues later

At 8 bar I would fit an inline PRV and then a small potable expansion vessel somewhere to reduce the pressure to 3-5-4 bar max in the house. It won’t reduce the flow that much, and you’ll not have the pressure bounce on the flow switch in the combi that you’re getting today.

Why mesh ..? What size is the slab..? if no differential movement I would just go with 100mm slab and make sure there are no stress points such as changes in depth of the hardcore.

here you go - pipestock are excellent for this sort of stuff. 150m coils as standard but sit down when you see the price of 32mm.. https://www.pipestock.com/mdpe/mdpe-pipe/mdpe-pipe-coils-blue

Don’t need a bull float - At 4m you can get a roller striker which is much quicker and easier than both tamping bar and power float as it skims the top surface flat.

yep Think up a trading name, set up a suitable gmail and then tick the sole trader box, they will then credit score you against your home address and an account will follow

Yes not unreasonable to see a premium on non standard laying patterns due to effort needed to do cuts etc

standard bit of process control kit - the good ones like this only use power when they are in operation so have no hold open / closed power use https://www.solenoid-valve.world/connexion/1-electrically-actuated-ball-valve-9-24vacdc-or-110-240vac-abvm08s