Under floor heating

[jprother]

Hi all

Fairly new here and about to start on a self build (not doing the work myself). I have been getting costing's together and I have some questions on UFH. (lots more questions to follow) ''

My setup will be a combi boiler, UHF on ground with radiators on 1st.

Spoke to a few UHF companies and they say that you just spur off the cold/warm feeds into the manifold - easy as that!

Been talking to a few plumbers and I am getting different responses, I don't want to appear as someone who does not know much and be taken for a ride.

One has said that UHF needs to be on a different Zone another said circuit, are these the same thing?

One said it should not me mixed with rads and should be independent as rust from rads with cause issues with UHF manifold.

Are the UHF companies right (just spur off) or do i need a separate zone? - No idea what that involves sorry.

Is the diagram below correct, do you need the values that are shown.

Thanks

Untitled

• jprother
• 3 Jul 2014
• 1

 

[Richardthe3rd]

You'll need to put both the radiators & the UFH on separate Zones, including zone valves/2Port Valves. Also give close consideration to the 'common' return from the two zones. The last thing you want is 'heat migration' to the wrong zone at the wrong time.

Controls wise; you may need a relay incorporated in control wiring that's pulling on the combi boiler central heating, but basically the micro switches on the zone valves can do this.

With time & temperature controls on both zones operating at differing levels, with careful consideration it should all be fairly simple.

 

[Norcon]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port and an inline strainer on the flow.
Both important!

 

[Richardthe3rd]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

 

[Norcon]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

The ufh wiring center is completely separate from the radiator zone wiring.

 

[Agile]

After many years with the BBC transmission department where I had to write "UHF" about 20 times a day. Changing to UFH has often been difficult.

Amusingly the OP has used "UHF" as well.

Tony

 

[Richardthe3rd]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

The ufh wiring center is completely separate from the radiator zone wiring.

Depends on the manufacturer & system Benny.

 

[Norcon]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

The ufh wiring center is completely separate from the radiator zone wiring.

Depends on the manufacturer & system Benny.

It's no difference what manufacturer.
When actuaters are fitted then you use a controller with volt free contacts for the boiler pump and boiler SL.
Some will incorporate a time delay relay for the actuater opening delay also and of course a transformer for 24v systems.

 

[Richardthe3rd]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

The ufh wiring center is completely separate from the radiator zone wiring.

Depends on the manufacturer & system Benny.

It's no difference what manufacturer.
When actuaters are fitted then you use a controller with volt free contacts for the boiler pump and boiler SL.
Some will incorporate a time delay relay for the actuater opening delay also and of course a transformer for 24v systems.

Benny, read the above to yourself & you'll see your contradictions.
Now, go away & milk the cows Farmboy.

 

[Norcon]

You don't need a two port valve to the ufh zone when actuaters are fitted which will be controlled by the wiring center.

The only thing missing on your diagram is an nrv on the mixing valves by-pass port.

Depends if; all these daft thermostats & actuators are fitted, and if the wiring centre can accommodate the radiator zone Benny.

The ufh wiring center is completely separate from the radiator zone wiring.

Depends on the manufacturer & system Benny.

It's no difference what manufacturer.
When actuaters are fitted then you use a controller with volt free contacts for the boiler pump and boiler SL.
Some will incorporate a time delay relay for the actuater opening delay also and of course a transformer for 24v systems.

Benny, read the above to yourself & you'll see your contradictions.
Now, go away & milk the cows Farmboy.

Insults the best you can do you big dumb jock?

Adding zone valves to multi zone manifolds is a total waste of money with no benefit and was mainly added by ufh companies that only had 1 relay on their wiring centres and therefore needed the Aux Switch that the zone valve has.

 

[Richardthe3rd]

Yes that's why I said it Benny. Now behave, stop making a complete t.t of yourself.

 

[jprother]

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• jprother
• 4 Jul 2014
• 1

Thanks all for the replies, lol at me saying UHF!! was in telecoms 20 years ago.

I have updated the drawing adding NRV and strainer, are they in the correct place.

Its my understanding that the UFH always needs to be at a base temp so it does not take long to heat up fully, so this would always need heat from boiler (not in summer heating off altogether ).

Just thinking i have never had any clock or wall thermostats before, just switched the heating on the boiler when needed and adjusted the radiator valves in rooms.

Could i have the same setup as before, no clock thermostats or zones
the only thermostats would be the UFH one's and we would control the bedroom by the radiator Valves (Off most of the time). so the only electric cable going to the boiler would be the one from the UFH ( missing in drawing)

see drawing below

Untitled

• jprother
• 4 Jul 2014
• 1

thanks

 

[Agile]

You would be better having weather compensation!

Tony

 

[Tipper]

You need to check out the Building Regs with respect to energy efficiency. Such things as separate thermostatically controlled zones are now a requirement.

You may also find it easier to balance the flows by using a Low Loss Header, effectively a large manifold, to supply the separate radiator and UFH circuits. The boiler pump will then take care of the circulation through the header with the rads circuit and UFH having their own pumps.

 

[Norcon]

Fit the strainer close to the blender on the A port side with the catchment guaze pointing down. Go up one pipe size bigger as they can be restrictive.

Fit the nrv to the B port.
Fit an isolator valve before the strainer and one before the nrv. Then the circulator isolator completes the valve station shut off facility.
A high limit stat should be fitted in case of blender failure. Some blenders are fail safe.
Job done.