UFH with hive MultiZone on Y plan

[mgrover]

So I have a combi boiler with a hive hooked up to it and from what I can tell its a Y plan(I think) with 1 zone.

So I crank up the heat on the hive it makes a call for heat and boom the boiler fires up.

Downstairs I want to install an UFH wet system which doesn't look like too big a deal, nuked all the rads downstairs and I was planning on using one of the rad pipes to hook up the Manifold but I've no idea if this will be separable down the line so we'll see.

Am struggling with two concepts a little bit, so I turn my Hive on, the water will come through at 65c or whatever, too hot for the UFH but thats fine, it'll have a blend valve to bring it down to the appropriate temp, and each downstairs zone will sort itself based on the actuators.

The 2nd bit am struggling to understand is, due to the wireless nature of this system am not sure how am going to signal the pump to enable?

can I get another Hive Zone and Thermostat. Hook that up to trigger the pump? So when I turn on the upstairs zone the UFH stays dormant or is just bypassed in the loop, but then if I want to turn on the UFH both zones will have to be active due the first zone is in charge of the boiler on signal and the second zone in charge of waking the UFH?

or is there an automatic way to trigger the pump for the UFH without needing a signal? like a certain temperature of water?

In the future I will get a plumber to zone it correctly but for now this will do, I understand it's not the most efficient but yah.

Cheers
Martin

 

[Deleted member 120897]

It may depend on your ufh system, but could you install a 2 port zone valve with a separate Hive controlling that system and then it’s just a wiring configuration.

 

[mgrover]

My issue is the manifold is nowhere near the boiler and no idea how those particular pipes plumb there.would it just be easier to fit the zoning valve next to the manifold?

 

[ShaunCorbs]

Are you sure it’s a combi boiler eg does it have a cylinder?

 

[mgrover]

Are you sure it’s a combi boiler eg does it have a cylinder?

yep, independant c30

 

[ShaunCorbs]

Can you take a picture of the port valve please ?

 

[mgrover]

honestly not sure what that is?

 

[ShaunCorbs]

How do you know it’s a y plan may I ask ?

 

[mgrover]

course ya can, thats probably a bit of presumption on my part tbh. figured if its not an S plan gotta assume its the Y Plan?

 

[ShaunCorbs]

I see as it’s a combi probably has no port valves so no plan

You need to get 2 x 22mm pipes and a 5 core cable back to the boiler

 

[mgrover]

I see as it’s a combi probably has no port valves so no plan

You need to get 2 x 22mm pipes and a 5 core cable back to the boiler

ah i thought y plan was basically no plan but yes you are correct.

thats my whole problem i dont want to do that or atleast am trying to avoid that till I can get a professional in to do it. but since am flooring now i kinda need to fit now.

so what am proposing is, i fit the manifold off one of the flow/return 15mm pipe left by the one of the old rads to supply downstairs manifold.

i hook that up to a separate hive zone and then i hook up zone valve to the flow line.

so to turn on the UFH you'd have to heat up the first "zone" which would be upstairs and effectively turning the boiler on, and then if you want UFH you turn on the 2nd zone which opens the zone valve.

that way I can have either just the upstairs heated, or the upstairs and downstairs heated, but I can never just have the downstairs heated.

also all my rads have thermostatic valves, so lets assume I closed all of valves, what happens to the return if the pump is pumping? do they all have to meet the return at some point in the house so they have independent returns? which would mean independent flows as well.

hows that sound?

 

[ShaunCorbs]

No as the likely whole downstairs ufh will be over the limit of the 15mm pipe

Also has there been a plan designed for the downstairs ufh pipework?

 

[mgrover]

its about 24sqm. and yes according to the beneath heat people. i havent had a chance to go order it yet.

also its 5 manifold ports.

 

[mgrover]

so got the documentation, they estimate 1.67kw for the two rooms total. Am told a 15mm pipe can supply 15.1kw. The other radiators downstairs I plan to replace with UFH. So I might be within the requirement. But we'll see how it goes.