BotusBuild

Yes, it is I've just posted on the FB page and will see what is said before trying anything else but thanks for the response.

Update (summary - pump running constantly!): Boiler COM and NO (normally open?) now connected to EVU 2 and 1 respectively (see pics) Pump connected directly to MA1. 2 PROBLEM: The pump (the one after the buffer tank) is on all the time whether the stat is set to require heat input. So, whether the wiring centre is calling for heat or not the UFH circulation pump is running. Settings which I think are relevant: Anyone shed any light on why the pump is always running.

Thanks @sharpener. On those schematics (3 pages), it shows the connection to EVU from the UFH wiring centre coming through 12s which is shown on the 3rd page as "DPDT relay (3rd party)". I think this is what our installer has put in (a double pole, double throw relay), on the basis we were installing another UFH manifold with a similar wiring centre setup (2nd manifold added but not the wiring centre, and unlikely to fit this). However, they've obviously got the pump wiring wrong. I will follow your advice above first (losing the installed relay along the way) and see how we get on.

I will make these changes in the next couple of days and report back. Thank you again.

Thank you @ProDave. Should I leave the circulation pump connected to the Valve terminals? Or move them to the above Pump terminals?

@ProDave, Is this what you are asking for? https://tioclimatesolutions.co.uk/wp-content/uploads/2023/12/TIOWIR0004.pdf

So, this has been my thinking all along. I did question this with the installers at the time, but I think they were less than receptive after I had already pointed out a mistake that they had to rectify. The setup is as follows (and the more I look at the detail, the more I am concerned): Vaillant heat pump providing for DHW and UFH. DHW is a 250L UVC and is working well. There is a Vaillant appliance interface (VWZ AI) and a SensoComfort (VRC 720/3). The first has all the wires and the latter is the how you do the settings. The UFH starts with a four port buffer tank fed from the ASHP. On the hot output is the circulation pump that pushes water to the UFH manifold. Each loop has a valve connected into a TIO 8 channel wiring centre, and we have one thermostat currently. Effectively we are running a single zone and I have actually left all the valves "open". With this setup, I would be looking for the UFH wiring centre to be controlling the "call for heat" to the heat source. As we have it physically setup, that heat source is via the buffer tank and so the wiring centre should send a signal to the circulation pump to turn on and send hot water to the UFH manifold. Wiring: From the installation instructions for the Vaillant interface, EVU is stated to be the Energy Supply Company contact. No idea why this is wired in as it is. From the installation instructions for the TIO wiring centre, Valve is supposed to be interfacing with a UFH Valve. There is a connector labelled Pump, with a L and N terminal. My plan is to attach a meter to the Pump connector, and turn the thermostat up to call for heat and see if there are volts on this connector. If so, surely the Pump should be connected to this directly?

Well, as stated, I want to replace the noisy electromagnetic one. Now, if your Q is "why do you need a relay", then the answer to that is "that's what the electrical wiring diagram called for".

We have an electromagnetic relay in our heating circuitry that was purchased at short notice so I was not able to research. It has a very annoying loud click. It's inside an enclosure in the plant room behind a solid door. I want to replace this with a silent SSR. The control and load are both AC. The load, a circulation pump for the UFH, is a Stuart Turner Pulse OEM 25-60/130, with a power consumption of 4.5 to 38W, which I work out to be <0.2A current draw. Will the 10AA version of this SSR be OK?

Thats where i got it from

That is where I put sealant. What goes on the end of the cill? Is that where water is coming out (leaking)? Maybe you need to put sealant at the end of the cill to stop the water coming out of the ends.

It is only a short single page piece

https://wastedwind.energy/2025-09-25

On other windows I have put SWS air tightness sealant on the out join between the window and the cill

We had a similar situation. Our problem turned out to be a combination of a manufacturing fault that meant water was staying inside the frame rather than draining out and an installation fault. Our fitters came back, removed the whole unit, dismantled the outer frame, fixed the manufacturing fault, then bunged a tube of sealant in each end of the bottom rail to stop any water getting out the ends. They refitted the frame with proper DPC. All good now

Heehee - when most electricity cuts happen 🙂

We should all build an Edison Generator 😁

What's below that screed? A concrete slab? If you're sure not chance of water ingress and it's already air tight, then just fill with expanding foam or your PIR solution as it's not going to to be a heavy foot traffic area 🙂

On our ground floor we have done as in Nod's picture above. The herringbone in my picture meets LVT tiles in the kitchen area, which orient across the arrows (L to R). There will be a brushed bronze 38mm "rail" where they meet

True

Herringbone 😁

Great progress Susie and David. Soakaway, cladding and ground works still on (one of) our lists 😁

Our waste pipes went vertically (as you'd expect) through the slab and the insulation below it and the went horizontal (with the needed drop of course) to the STP. Yes, we had to cut the mesh/chair/castle makeup to accommodate this. It is normal.

Likely it is such a metal lintel behind those vertical laid bricks. Without removing one you'll never really know for sure, but safe to assume it is there. Will the weight of the pergola be taken by vertical posts and at four(?) corners of the pergola? If so, then the attachment to the wall is mainly to stop it moving vertically away from the wall. Still need to be strong fixings and as long as you drill carefully and jo bricks are broken in the process you should be OK. Fixings can go in the mortar. May be use threaded rod and resin to fix the ledger (or pergola directly) to the wall.