Advice needed - zone valves

[leedjc]

I'm in the middle of installing a new heating system in our house.

The setup is 4 port manifold upstairs feeding the 4 upstairs rads, all controlled with heatmiser neostats.

Downstairs is another 4 port mixer manifold feeding 4 UFH zones, again controlled with heatmiser neostats.

The flow/return is 22mm to the downstairs manifold, with the upstairs flow/return being teed off this.

The UFH supplier has told me that zone valves will be required so that these two circuits can operate independently. I cannot see how that these are necessary. In my mind the boiler won't fire until a stat calls for heat, and each circuit is independent due to the actuators on the manifolds.

Of course if it was a more traditional setup with the rads not running off a manifold, I can totally see them being required.

If they are required, of course, I'll put them in, just trying to save spending £100 odd if not really needed!

Any thoughts on this is more than welcome!
Thanks
Lee

 

[John D v2.0]

Common sense says you're right, no point putting 2 valves in a row.

 

[leedjc]

Thanks, that's exactly what I thought, but wasn't sure if there was something I hadn't thought of!

 

[ianmcd]

which actuators are you using ?

 

[leedjc]

They're Heatmax ones, but think that these are rebranded from something else...will have a look at them when I get home

 

[leedjc]

They are the same as these

https://www.elementshop.co.uk/2-wire-thermal-actuator

They're normally closed

 

[PullerGas]

Is there a control centre for all the loop actuators to be wired into??!!

A lot of times it's easier to control the boiler via the micro switches on the zone vavles. Generally, your controls or UFH supplier will provide a wiring schematic.
Me I'd fit zone valves regardless.

 

[leedjc]

Yep, there's a wiring centre for each manifold.

Each one can call to heat from the combi individually

They've provided standard wiring/plumbing schematics, but not any that fit the dual manifold system I've got

I asked for some earlier this morning, but aside from being told that each manifold should be zoned, have not heard anything back

Is there a control centre for all the loop actuators to be wired into??!!

A lot of times it's easier to control the boiler via the micro switches on the zone vavles. Generally, your controls or UFH supplier will provide a wiring schematic.
Me I'd fit zone valves regardless.

 

[PullerGas]

Do these wiring centres have a relay to pull on the boiler & what voltage is it??

Most combi boilers are wired via the Room Thermistat loop/link.

Perhaps you'll just need another relay to pull the boiler on.....dunno??!!! I need to see the controls schematics.

 

[leedjc]

The wiring centres can switch with 240volt or 0volt, depending on the application. Each room has got its own thermostat. When the stat calls for heat, the wiring centre will activate the appropriate actuator and call for heat from the boiler at the same time.

So in effect each room is its own zone and the actuators act as zone valves...that's why I can't see the point in additional zone valves

 

[PullerGas]

Are all Room thermostats time & temperature controllers?

You'd save me a lot of time if you posted up the schematic. I'm at my wife's funeral & it's a free Bar, her family are paying - so I want to take full advantage.

 

[JimCrow]

Is that the third or fourth wife Dickie?, I've lost count.

 

[leedjc]

Well, I hope you had a good night

Yes, they are all independent. I'll draw up a schematic later and post it up

Are all Room thermostats time & temperature controllers?

You'd save me a lot of time if you posted up the schematic. I'm at my wife's funeral & it's a free Bar, her family are paying - so I want to take full advantage.

 

[Dan Robinson]

Zone valve is pointless. Relays will be in the wiring centres,

 

[leedjc]

Here's a (very) rough drawing of the setup...hope this helps!