Two manifolds for one system.

[Lemna gibba]

We have a two phase approach to remodelling our house. At the moment we are replacing a conservatory with a single story extension to make a large kitchen area. This will have well insulated floor (150mm PIR) and we are putting UFH in. The room is about 30 m2, it will have two loops but obviously be a single zone.  We've had some heat loss calcs done and worked out the pipe spacing and I'm playing in loop cad with designs. 

 

The rest of the ground floor will be done in 4-5 years time. Almost certainly add an additional 4 loops. 

 

At the moment we will run the UFH from our boiler, but our plan is as soon as we can do phase 2 and insulate the whole house to run the whole thing from an ASHP.  We do not want to dig up our newly laid kitchen floor then. 

 

It would be way easier to have 2 manifold locations (all be them separated by only 30 cm of wall). One of them for the phase one renovation, and the other for the phase 2. This is because we don't want to lay a porcelain floor then dig part of it up in 4 years.

 

The alternative would be to knock through a part of the wall, install a small beam, buy a 6 -port manifold now, use 2 of the ports but have everything ready for the next phase. The problem is this would come out into our hall. Currently this is (I believe) an uninsulated concrete slab which we will dig out in phase 2. I really don't want to start digging out a section now or try digging around UFH pipes. 

 

Can you see a problem with having two manifolds other than price.

 

 

 

 

[JohnMo]

You can easily join two manifolds,so that would not be an issue.

 

One thing to concider for phase one is boiler short cycling, the heating times for the radiators and UFH are very different, so you could end up with only the UFH on. The boiler is likely to shirt cycle.

 

Have a read through this thread, may answer some questions you didn't have.

 

 

 

[Lemna gibba]

Thanks, I realised that I needed two-port valves. That thread was very useful highlighting the need for a buffer, but I'm not keen on sourcing one from ebay after that saga!

[Super_Paulie]

It was an annoying situation all round and if I could go back I'd just get one from a store that I could return.

 

Hasn't leaked though, but looks a bit silly with a tap stuck on top.

[Lemna gibba]

Hi @Super_Paulie,

 

Thanks for commenting. I found your thread quite hard to understand. I think in the short term our set ups are quite similar with mix of rads and UFH in part of the ground floor. I assume that you would still do a buffer if you were installing something similar again. 

 

Cheers, Tony 

[Super_Paulie]

I haven't fired it all up yet as I'm still at the insulation stage in my roof. I assume it'll be ok but it was a steep learning curve and @Nickfromwales and @JohnMo helped loads amongst other forum members, all very helpful. I didn't even know what a buffer tank was until they helped me out, now it's obvious it would have been required in the way I want to do things.

 

I've tested the electronics and valves and its all good to go in the near future, but it was stressful and confusing at first. I'll draw it all out at some point for future reference but attached is how it's all controlled. Zone valves and buffer are at the upstairs/loft.

[Nickfromwales]

20 hours ago, Super_Paulie said:

I haven't fired it all up yet as I'm still at the insulation stage in my roof. I assume it'll be ok but it was a steep learning curve and @Nickfromwales and @JohnMo helped loads amongst other forum members, all very helpful. I didn't even know what a buffer tank was until they helped me out, now it's obvious it would have been required in the way I want to do things.

 

I've tested the electronics and valves and its all good to go in the near future, but it was stressful and confusing at first. I'll draw it all out at some point for future reference but attached is how it's all controlled. Zone valves and buffer are at the upstairs/loft.

Nice and neat, top job 🫡👌

[TonyT]

Good to see good work being installed no matter that it’s in a cupboard. Looks great!