ProDave

Can you post a picture of the UFH manifold controller, if possible with the cover off and close up so we can read the terminals. A lot of them have a "volt free" relay contact as the "call for heat" from the manifiold in which case you would use a 2 core cable to the boiler and it would not matter if they were on different circuits.

No chance of the council here doing anything. There has been a blocked culvert here for all the time we have been here. In winter we in effect have a permanent ford down the road, the water runs across the road and then down through the garden of the neighbour to our old house (I made sure the ground level was banked up along our plot to stop it entering). Just about everybody has complained to the council several times and the best they will do is come and stick a patch of tarmac in when the ford washes away part of the road surface.

We have a planning condition that says we must not let surface water from the plot onto the road. Not at all difficult to comply with as our plot is lower than the road. Now if only they imposed the same condition on highways "you must not let surface water from the road onto our plot"

What are your hot water times set to? As I tried to explain, when it starts heating the hot water it will STOP heating the rooms for the duration of that. So if your hot water heating has come on, your radiators will go off for a time. On my unit you can set how long the hot water function stays on and then the time before it does more hot water heating. Mine is set to 30 minutes on (the default setting) and then 30 minutes off (the default I think was an hour) But this is a more complicated setting than just setting programmer times. I believe the logic in this timed arrangement for hot water is partly not to deprive the house of space heating for too long at a time (that would not be an issue in my house) and also because the heat pump is working harder when heating hot water, by limiting the HW time will reduce the likelihood of it needing to defrost. Different units treat this in different ways so ask the guys when they come round to explain how your unit deals with this and agree between you how you would like it set to operate.

So to ensure a silent night time, set the set back temperature to 5 degrees and accept if there is an off period in the middle of the day the house might get very cold. If you can't accept a very cold house in the middle of the day then make the morning heating time stay on for longer and make the afternoon heating time start earlier.

A couple of points. I think we determined that although @zoothorn unit is a split unit, it has the gas compressor in the outside unit, so all that i in the inside unit is a heat exchanger, water circulation pump, expansion vessel and some controls. Apart ftom the pump in there it should be no more noisy than my monoblock unit. +1 to the time settings being wrong. Before you next get Vailant out, write down on a bit of paper what times you want the heating on and what temperatures you want and ask them to set it to that. For instance my heating comes on at 6AM and stays on all day until 9PM with a set temperature of 20 degrees. Of course that does not mean it runs all day unless it is really cold, it will turn on and off as the room thermostat dictates but after 9PM will not come on even if the house goes cold. In your system you would achieve that by setting the temperature between your required times to 18 degrees or whatever you are comfortable with and setting the night temperature to say 14 degrees. If you want to ensure it NEVER comes on at night, even when it's damned cold, set the night time temperature to 5 degrees, but then you must accept after a really cold night it might take longer to heat the house in the morning. That is the price you pay for a silent night. Now hot water time settings. One feature of heat pumps is they usually only heat the rooms, OR hot water, never both at the same time. I have my hot water set to come on at 11AM and then stay on until 8PM It is not often anyone showers here in the morning but if they do there is enough hot water for one shower in the morning still in the tank. the not coming on until 11AM is to ensure maximum use of solar PV and we have some shading issues that mean much before 11AM generation is low due to the shading, Now your dilemma between wanting a warm house when you get up and wanting it silent at night, is it WILL need to come on before you get up. So you have to accept a time in the morning where you are prepared to accept the noise it makes to warm the house before you get up.

The basic "control" into the heat pump is heating on or heating off. That is the only "control input" that my ASHP has. From that you can derive any operating mode you want. I chose simple time control with a programmer and simple fixed temperature room thermostats. but you could instead have one or more programable room thermostats that would set different temperatures at different times of day. You seem stuck with people that do it their way and are not open to making changes so it suits what you want. Hence why I suggest you might try someone else. You would be surprised how many times I have to go and sort out the wiring of heating systems that are not operating as the customer wants because so many installers to be honest don't actually understand what they are doing.

And a mild climate.Mine has been on for a month.

Yes the only noise I hear from mine is the gentle hum of the water circulating pump. That is the same type of water circulating pump you would use with a gas or an oil boiler, so the noise would be the same regardless of what heating system you had, and is not a heat pump issue. It does not bother me asleep and it does not wake me up in the morning, but at night i prefer to go to sleep in a silent house without even that low level noise. My controls are simple. A normal type of central heating time clock to set what times the heating and hot water functions are on (can be set to different times) and a room thermostat in each room. If you wanted to profile it for different temperatures in different rooms at different times of day or night, you would simply have a programmable thermostat or just a master programmable thermostat instead of the time clock. I suspect the issue here is you got a basic install by a team of fitters that just do basic installs. If tou want better more versatile controls perhaps you are going to have to pay someone better to change things?

It's all done with a conventional central heating type programmer. It comes on at 6AM to ensure it's warmed up by the time we typically get up about 8AM

It goes off at 9PM and comes back on at 6AM

Are you saying the issue is the joists are sagging mid span? Or they are not level at the ends? Or both?

If a Hep20 one fits, that's what @pocster wants to use isn't it?

To stop condensation forming and dropping onto a ceiling below. Up here at least, the incoming mains cold water can be VERY cold in winter.

And I will bet a standard tap connector will be too fat to go down the tube hence it will need the special one that should have come with the kit.

Nail hit on the head. Just pester those installers until they come back and fix it.

Okay, another try. With that end off, screw the "end" onto the tap. How much tap thread sticks out the other end? Is there enough thread to get a tap connector on? And if so will a tap connector fit down inside the tube?

Mine is 5kW and all under floor heating.

So your "shroud" screws onto the tap and will seal (with ptfe tape?) What do you see looking into the bottom end of the shroud then? What is the function of that grub screw I see? Is that at the top end or the bottom end? I am still not convinced this is going to look right? It is still going to be a deck filler mounted onto a couple of poles. you should have bought a proper floor standing tap, e.g.

Do let us know how you get on. With say a 200L UVC, you fill the tank with water at say 50 degrees, then turn on the hot tap and you will get 50 degree hot water up to the point you have drawn all 200 litres out of the tank and it will then quickly go cold. Now fill your 200L thermal store to 50 degrees. Turn on the hot tap and you will get 50 degree hot water. but by the time you have drawn say 100L from the hot tap you will have removed half the stored energy from the tank, so the water that is left in the tank will be a lot less than 50 degrees now and so the hot water temperature will be lower. So you either need a very much larger thermal store, or you need to store the water at a much hotter temperature with a thermal store. They usually have a thermal mixing valve to regulate the delivered water temperature. As Heat pumps don't do much over 50 degree hot water, the results with a thermal store are likely to be disappointing.

Perhaps it's time just to bite the bullet and pay a different, competent plumber to come and sort the niggles if you are convinced the supplier can help no more and are not prepared to fight with them?

This is a garden room. What's wrong with raising it another 100mm to get more insulation under the floor?

Are the 2 rooms in the garden room completely separate? I would be tempted to fit one of the cheap air conditioner units that can be bought for not a lot over £500. They are a small air to air heat pump that can do heating and cooling. I believe you can for not much more buy them with two inside fan units so one for each room. I would keep garden room and house heating separate.

Yes just call the installers back. Don't even mention Vailant replaced part of the HP. That will not have cause the loss of pressure and dribbling tundish issues.

How should I know, I was not there? If you don't know, nobody does.