Zoned mixed system heating over 2 floors & 16mm pipe reducers

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What's the best way to have zoned wet UFH downstairs, with zoned radiator system upstairs, using the same brand wiring centres, so that my heating can be controlled from one app system/hub instead of two?

The way i was thinking of doing it was the usual for the UFH, but upstairs buying another manifold and supplying each radiator from that as a star circuit instead of radial, meaning less joints.

A lot of UFH systems are 16mm not 15mm. Can you get 16mm reducers that aren't restricted on the inside diameter?

Are there any other ways to do it? is 15mm to big to run to 8 radiators?
What size pipes are usually used for new build radiators these days? I've only used 10, 15, 22.
 
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The plumbing style (manifold or trunk mains with drops) won't itself alter your control system.
While you're planning this setup, consider that things have moved on- for not much more than the cost of a single zone valve you can get sets of Bluetooth or Wifi TRVs for each rad...
 
I use ufh manifolds for rads so can control each rad individually, you can run 15mm pipes and connect to the manifold using 15mm conex connectors and if you use same manufacturer as your existinf ufh all the controls can be run off the same app.
 
Sorry I maybe never explained well enough in the first post, I'm aware that systems have move on and some people now prefer to have their heating split into zones, thats why i was asking about the smart connectivity. I've done a good bit of looking into it all but stuck with a couple of things that others who fit these for a living or have recently installed would know more about.

I prefer wired thermostats over wifi. it works without issues and i have the opportunity to add all the wires on a new build.

UFH i'm having a central manifold with multiple zones and 4 programmable wall stats and a screed stat for each with actuators on the manifold.
Upstairs will be radiators, 3 i would like on open circuit and 5 also controlled by actuators and wall programmable stats. It seems my options are to either:

1.Buy another UFH manifold and connect all the radiators to that and use actuators to control the zones.
2. Connect all radiators as usual and add some brand of TRV actuators to the radiator themself. There doesn't seem to be many available and wired is less choice.

My main question is, do the upstairs TRV actuators or the manifold actuators and/or extra wiring centre need to all match the UFH brand to make it all compatible to work with one app? I don't want a Heatmiser app for downstairs and some other app for upstairs. If it wasn't for whole house smart connect there wouldn't be an issue.

I use ufh manifolds for rads so can control each rad individually, you can run 15mm pipes and connect to the manifold using 15mm conex connectors and if you use same manufacturer as your existinf ufh all the controls can be run off the same app.
Does this mean for upstairs you use a manifold that only takes 15mm pipe? Most UFH is 16mm apart from polyplumb, Would be nice if all pipe sizes matched so less pipe wastage and same manifolds and fittings, technically if it was all 15mm all connections could be accessible at the rads or manifold above floor height so no buried joints. 16 to 15/10mm reducers would start adding a lot more joints.
Some UFH pipes only go up to 60 degrees too, the PERT stuff.
 
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Either Heatmiser Neo or Salus Smart Home will do what you want - both offer wired thermostat options for smart home control. Salus have a better range of products, but aren't compatible with any of the voice assistants, whereas Heatmiser works with the voice assistants but only does thermostats and smart plugs.

Using a manifold for the radiators is a great way of achieving this, and you can use the 16mm UFH pipe (best to go for a system that uses Pex-Al-Pex or Pert-Al-Pert). There are adapters available which allow a 16mm pipe to be very unobtrusively connected to a 15mm valve. I recommend IMI Dynatec Eclipse for your manifolds - far superior flow control to others on the market.

Size your radiators for 60°C flow / 40°C return temperatures and you won't need to worry about maximum pipe temps (although the pipe types mentioned above will happily go to higher temperatures if required). Doing this will mean your boiler runs efficiently too.
 
Either Heatmiser Neo or Salus Smart Home will do what you want. Salus have a better range of products, but aren't compatible with any of the voice assistants, whereas Heatmiser works with the voice assistants but only does thermostats and smart plugs.

I've been looking at the Salus & heatmiser a lot, they seem popular, checked some reviews on google & trust pilot, heatmiser was good, salus got slated for after sales, but then another person i spoke to said heatmiser has had a recent software update which has caused lots of glitches that haven't been fixed, not seen anything on it myself. Just had a quick check & it looks like Salus has an android app but smart only works if you have RF wall stats. I think Heatmiser you plug an attachement into the wiring centre that speaks to the hub. Are these the two most popular brands or is there other decent ones? I'm not clued up on what smart features others offer, lights would be good but i didn't think heating hubs could control them.

There are adapters available which allow a 16mm pipe to be very unobtrusively connected to a 15mm valve. I recommend IMI Dynatec Eclipse for your manifolds - far superior flow control to others on the market.
So them 16-15 reducers just slide inside the pipe & connect perfectly to standard 15mm radiators valves, does it reduce the inside diameter of the pipe much? There will be some places i can't get a sweeping bends to come out of a wall for towel rails on a stud wall, so i'll need 90 degree elbows to go from vertical to horizontal, are you allowed hidden compression joints with building regs?

Not heard of dynatec, I didn't think there'd be much flow difference as they all look similar shape, but wondered if it's best to have brass nickel or stainless steel to last longer & make sure the fitting don't bind. I've looked at JG speedfit, polyplumb & Emetti so far.

Size your radiators for 60°C flow / 40°C return temperatures and you won't need to worry about maximum pipe temps (although the pipe types mentioned above will happily go to higher temperatures if required). Doing this will mean your boiler runs efficiently too.
Would this be delta T30 if it even goes that low, 60/40 = 50 average minus 20 degrees room temp? My concern with going too low is one of my rooms being 6m x 4.7m, not sure i could get one radiator to heat that size room at low temp.
 
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They're the only two I can think of with wired thermostat options on a multi-zone system and app control. The Salus can control lights, along with a host of other things, and comes with a 5 year warranty. I've fitted it and was impressed. Only downside as mentioned is that there's no voice assistant integration. Don't think of it as a heating hub, think of it as a smart home hub.

Correct on the reducers. There's a slight restriction there but not enough to hinder performance. Yes, compression joints in walls are permitted.

IMI are an excellent company based in Dunstable. They're Dynatec manifold has the advantage that the flow rates on individual circuits don't change when other circuits turn on or off, giving more consistent heating. Each circuit is completely independent. Other manifolds don't have this - if one circuit shuts down, the flow rate (and therefore heat output) on all the other circuits will change.

If you've got a room 6.0×4.7 I'd recommend having a radiator at either end to give a better spread of heat
 
You dont need adaptors, here is a rad manifold that I installed
IMG_3400.JPG
all done in 15mm pipe.
 
They're the only two I can think of with wired thermostat options on a multi-zone system and app control.
I called Salus earlier and their smart connection only works back to the hub if you use their RF stats they said. So that only leaves heatmiser wired now. I thought all wired systems worked by having the actuators and thermostats wired back to the wiring centre, and then from there if you want to add smart controls, your wiring centre or a plug in, into the wiring centre then speaks to a hub thats plugged into your home router?

Salus wireless thermostats must speak direct to the smart hub at the router which is strange, they send RF to the wiring centre to call for heat, but the wiring centre cant speak to the hub for smart control.

Do you know which parts need o be compatible to work. Could i use a heatmiser wiring centre and smart hub, but have a different brand of actuators at the manifold, they all just have a couple of signal wires don't they, or do you also need heatmiser actuators to match?
 
Picasso, Thanks for the info & picture. Is that 15mm multilayer or standard grey pipe? What size were the manifold ports you bought, 15 or 16?
For the 15mm pipe do you add the 15mm eurocones or 16mm cones? Most manifolds are 16mm but if using 15mm pipe i wasn't sure which you pick.

Reason i thought 16mm stepped down was useful, is so i'm only buying one lot of pipe for whole house, any spare from the UFH can be used on the radiators. 15mm for radiators only does make more sense.
 
Hmm, I don't think that's right - the wired SQ610 stats should work too. They all use a wireless connection to the hub though, there's no wiring to that
 
Not done it myself, but I like the idea of using a underfloor manifold to feed rads. As I see it now, the pros and cons are:

Pros:
1. Centralised electrical control of each radiator, individually or in groups.
2. Tamperproof radiator balancing (control flow to each rad at the manifold) with visible flow indications. Rads have L/S at both ends. User can only tamper with the local thermostat.
3. Each rad can be securely isolated for maintenance/modification. Towel rads can be used in 'summer mode'.
4. One central location means more likely to be 'future-proof'.
5. A visual indication of water quality is present.

Cons:
6. Much more pipe needed at installation stage - may be very congested near manifold
7. More pipe means more water content, means slightly slower warm-up times.
8. Unless centrally adjustable by wi-fi/comms any changes to heating schedule will be laborious and protracted.
9. End-stop switch versions of the actuators needed, or an expensive/overpriced UFH wiring centre needed to give demand to boiler.
10. For long runs to distant rads in large houses a supplementary pump may be needed.

Overall though, in a new build where you have the space and the money to implement it properly, it's a good option.
 
Muggles, the Salus person in technical couldn't answer any basic questions so i think they must of been standing in, they said it wasn't their normal position or something along them lines. I might have to re-enquire after reading some info they sent via email & what you said.
I asked if there was no way i can add something to the wiring centre that speaks to the hub like heatmiser and they said no.

It doesn't make sense to me, if their wireless stats speak to the wiring centre, and the wiring centre speaks to the hub/router by Rf like all do, then i see no reason why a wired stat to the wiring centre would be any different. I was told Heatmiser actuators are thermal, others are electro thermal, so better, I need to know what the difference is then if they arent as good I can try other actuactors.

MELDREWSMATE, I had all the same pro's but what is No.3 summer mode? Do you just mean closing off all other radiators & leaving the towel rails on an open circuit like i'm doing?

Cons: 8 is a big reason why i wanted the wired smart control, no batteries, always have a signal full strength, easy to change settings to all.
9 I don't know what that is.

You could add wired or RF actuators to your current radiators to prevent pipe altering.
I'm considering having the UFH on a separate plate heat exchanger, so the dirty radiator water doesn't mix with the clean UFH system. It was an idea i still need to look into. Heating side will have a mag filter of some kind on the return.
 
Yeah, like everyone else they're struggling with staffing issues at present I think, but you could always call and ask for a call back from one of the tech team.

As for actuators, I believe they're all the same but just have slightly different descriptions. They operate on the basis of a small heater coil heating up a sealed capsule. The resultant expansion drives the valve open.

Why would your radiator water be dirty on a new system? A plate heat exchanger will significantly reduce efficiency.
 

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