ectoplasmosis

I have a load of these around the house, they work very well. The phone app is very convenient, with graphs over time etc. They come with crappy AAA batteries that last a couple of months; replacing with decent quality alkaline AAAs lasts ~6 months for me.

Your 40C flow design temperature will be met at the outdoor temp design temperature, i.e. depths of winter. All other times, the system will be modulating the flow temp based on the weather compensation curve. If you “always wanted no more than 35”, then you should have conveyed this to your installer and they would have sized the emitters for a 35C design temperature instead.

Would love to know more about your project!

As several have tried to suggest already: your best bet is to get the installer back to balance your system. It’s not that difficult to achieve. You don’t need to add or change anything right now. The system needs to be balanced and commissioned properly. Begin with this goal, and see how you go.

Why do you want them to be controlled separately? All this would do is decrease efficiency, and increase the risk of defrosting problems in winter due to lack of water volume. Your current setup, with open-loop and no TMV or secondary pump on the UFH, is best-practice for achieving best comfort and efficiency... providing that the emitters have been sized/specified correctly! From everything you've said, it sounds like the system is probably designed and installed well enough, but the radiator circuit has likely not been balanced/commissioned fully, causing the rooms with radiators to undershoot the target temps. I'd advise getting the installer to balance the whole system, then tweak the heat curve setting to achieve suitable flow temps which keep all rooms at their intended temps. I really wouldn't recommend installing any kind of zoning control, or thermostatic mixer on the UFH, this would only increase running costs.

What is the 'room stat'? Do you mean the Vaillant Sensocomfort controller? If yes, which weather-comp 'mode' is it set to (Active/Inactive/Expanded)? What type (K2, K3 etc) of rads do you have upstairs, and how big are they in relation to room sizes? You should have had a 'radiator schedule' document with these details as part of the install/commissioning process. You should not have to fit a TMV or auxiliary pump to your UFH circuit, providing the radiators have been properly specified. My house has UFH downstairs and rads on the upper 2x floors, no mixing valve, single flow temperature. Works perfectly, whole house stays at a constant 21.5C.

You'll be gaining a dry pipe! Don't know why it's so difficult to grasp... Just fit the pipe lagging, and stuff a load of mineral wool into the hole until it's flush with the pipe lagging, job done!

We have a GU Secury auto-deadbolt 4-point lock; no handles outside or inside, slam shut, opens via the Euro cylinder key. Works really well.

Whats this stuff like? The price looks good, but how long will the adhesive last?

Lots of data here: https://community.openenergymonitor.org/t/vaillant-maximum-output-capacity-testing/27221

We need to stop quoting/using Vaillant datasheet numbers in relation to sizing; they are peak output figures which cannot be achieved over any length of time in UK winters with frequent defrosting. There’s a reason the units are named ‘7kW’, ‘10kW’; these are roughly the sustained outputs they’re capable of under prolonged defrost conditions (providing there’s enough water volume to facilitate the defrosts).

I think you came to see our ASHP in Leyton...? Small world if so! I can't stress enough how much I'd avoid having your unit up on a roof. Even if your neighbours don't mind and you somehow avoid low-frequency reverberation through the fabric of your house, the rubber feet always harden over time, exacerbating the vibration transmission. There are loads of turnkey solutions for hiding an ASHP these days; off the shelf shrouds, vinyl wrap etc. Have a look around.

Primary Pro. UV stable and moisture resistant.

That ‘insulation’ won’t be doing very much insulating I’m afraid… huge gaps between the PIR and the inner blockwork skin. As for sealing the cavity reveals, there are numerous ‘insulated cavity closer’ products out there. Pick the one that matches your cavity depth, target price and performance.

Thanks for the tips... however, neither of these are timber-frame alu-clad. We're specifically looking for alu-clad timber with a clear-lacquered internal finish, to match our existing Velfac 200E units.