oranjeboom

UFH thermostat wiring, floor probes

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So I'll probably have 1 thermostat for each room and am using Wunda's wired touchscreen units W91.713:

 

image.jpeg.ece523f7aaf36b59590e13bed769b6ba.jpeg

 

From what I can work out, I will need to wire up each thermostat to the manifold's wiring centre (4, 3) and also power (2,1)from the consumer unit/fuse box, but preferably a nearby fused spur?

 

Image result for wunda w91.713

I have two rooms that will have a floor probe, so that gets wired into 7 and 6?

 

2 more questions:

1) what cable back to the wiring centre?

2) What cable for power? https://www.toolstation.com/shop/p71065?

 

Electrician will be checking my handiwork/making the final connections, but I wanted to get the buggers on the walls and cabling in before I do some more boarding up.

 

 

 

Edited by oranjeboom
Found the answer to that one qs!

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Floor probes! didn't read somewhere that it's best to use air temperature probes to control UFH?

 

Maybe this is what I was thinking about -

 

Edited by Triassic

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Just now, Triassic said:

Floor probes! didn't read somewhere that it's best to us air temperature probes to control UFH?

Yes, I think you are right. After all, you're more interested in the air temp to set the room by rather than slab temp. But as I have them in the slab I thought I may as well connect them. I presume I can over-ride the probe. If not, I just disconnect the wiring at a later stage.

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I had a couple that came with floor probes. Think they were for the bathrooms on separate zones but not used. @PeterW will remember. 

 

 

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4 hours ago, newhome said:

I had a couple that came with floor probes. Think they were for the bathrooms on separate zones but not used. @PeterW will remember. 

 

 

 

Yep

 

It was 9 zones with air temps and 2 with floor probes, main bathroom and master ensuite. 

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But why do bathrooms have floor probes and don’t use the air temp? Because of steam from the shower etc? 

 

Or is it because the stat is sited outside the bathroom? 

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13 minutes ago, Nickfromwales said:

Something said during the “McEwans event” must have hit home. :D 

 

I do listen sometimes, even to drunken Welshmen! :D 

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Okay, so I worked out that ports 7 and 6 are for the floor probe - anyone know if the probes are polarity sensitive or can I user either port?

 

Can anyone shed light on my other questions?

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29 minutes ago, oranjeboom said:

Okay, so I worked out that ports 7 and 6 are for the floor probe - anyone know if the probes are polarity sensitive or can I user either port?

 

Can anyone shed light on my other questions?

 1.5 T&E and clearly label each wire...

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Thanks @PeterW ! Will I need to run each back to the consumer unit or can I connect to nearest available supply? It's mostly all routed above in the loft, so hopefully I don't need to connect each back to base!

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On 12/09/2018 at 11:19, oranjeboom said:

So I'll probably have 1 thermostat for each room and am using Wunda's wired touchscreen units W91.713:

 

image.jpeg.ece523f7aaf36b59590e13bed769b6ba.jpeg

 

From what I can work out, I will need to wire up each thermostat to the manifold's wiring centre (4, 3) and also power (2,1)from the consumer unit/fuse box, but preferably a nearby fused spur?

 

Image result for wunda w91.713

I have two rooms that will have a floor probe, so that gets wired into 7 and 6?

 

2 more questions:

1) what cable back to the wiring centre?

2) What cable for power? https://www.toolstation.com/shop/p71065?

 

Electrician will be checking my handiwork/making the final connections, but I wanted to get the buggers on the walls and cabling in before I do some more boarding up.

 

 

 

I have come into this thread part way through so excuse me if I have missed  something.

 

This is wet UFH isn't it?

 

Then that looks the wrong thermostat.  That has power into  1 and 2, and 3 and 4 connect to an electric UFH mat.

 

The thermostat for wet UFH just wants a volt free contact for the manifold controller.  You normally connect that to the UFH controller with a 3 core cable, it gets it's power from there, not direct from the consumer unit.

 

Apologies if I have got the wrong end of the stick and you are using electric UFH

 

 

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Ah, that’s interesting as that’s the stat that Wunda supplied with my wet UFH manifold??? Yet to wire it up.

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Depends whether the control box and actuators are 24v or mains at a guess

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On ‎12‎/‎09‎/‎2018 at 11:19, oranjeboom said:

From what I can work out, I will need to wire up each thermostat to the manifold's wiring centre (4, 3) and also power (2,1)from the consumer unit/fuse box, but preferably a nearby fused spur?

 

Not certain but I think the boiler/ASHP, all pumps and stats etc should be powered from one fused spur near the boiler. If the FSU isn't near the boiler I think you need a plaque near the boiler stating where the FSU is located. 

 

You never want to have a situation where the service man flips off the FSU only to find the stats are still live.

 

How many manifolds do you have? If more than one you might need to OR together the two "Boiler Enable" (BE) signals to produce one BE in a way that doesn't cause interaction. If just connected together you might find the pumps on both manifolds start when only one is calling for heat. Depends how the wiring centre is designed. I had to use relays but then my system was a different make.

Edited by Temp

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18 hours ago, ProDave said:

Then that looks the wrong thermostat.

 

I couldn't find the W91-713 only the E91-713 on their web site.

 

However I wonder if the W is for wet and E is for Electric... 

 

Elsewhere Google found..

http://www.tpsthermalcontrols.com/products/57/

 

The E91-713 is a weekly digital 230v only programmable thermostat with a LCD touch screen ,This unit has 6 events per day with manual mode and programmable mode which can be selected

suitable for both electric and water based underfloor heating available in 230v only Price Excludes VAT

 

 

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In the manual for the E version here..

http://www.wundafloorheating.co.uk/wp-content/uploads/2018/05/E02-generic-E91-touch-screen-Stat-27-4-2018.pdf

It says..

 

"7RLE Not available on this model. Potential free output and main output synchronous/ asynchronous direction" and "Do not adjust KEEP FACTORY SETTING = 00"

 

So the E version might not be able to do volt (aka Potential) free?

 

Best give them a call to check you have right version.

 

Perhaps their set up doesn't need/use volt free stats?

 

 

Edited by Temp

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Check what the UFH controller wants.

 

IF the UFH controller is expecting a switched L then you can use that thermostat, Terminal 4 will be the switched L and just ignore terminal 3.

 

IF the UFH controller is expecting a low voltage or volt free contact, you cannot use that thermostat.

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On 13/09/2018 at 18:03, dpmiller said:

Depends whether the control box and actuators are 24v or mains at a guess

 

Both are from Wunda again.  The wiring centre is 230VAC H-box-12: https://cdn.wundatrade.co.uk/wp-content/uploads/2017/08/E07-Generic-H-Box-12V1.2-wiring-centre-09-10-2017.pdf

 

The actuator ("Stellantrieb 2 / Drive") is also 230VAC:

 

Stellantrieb-2-Drive-230V-2W-NC-M30x1-5-Thermal-ActuatorStellantrieb-2-Drive-230V-2W-NC-M30x1-5-Thermal-ActuatorStellantrieb-2-Drive-230V-2W-NC-M30x1-5-Thermal-Actuator

 

 

 

Thanks @Temp

I don't have a boiler, just two eDual Uniq sunamp units which will be within 2m of the downstairs UFH manifold. I will have a manifold upstairs (where I will have only 1 bedroom and ensuite, but may not end up installing UFH up there).

 

On 14/09/2018 at 13:50, ProDave said:

Check what the UFH controller wants.

 

IF the UFH controller is expecting a switched L then you can use that thermostat, Terminal 4 will be the switched L and just ignore terminal 3.

 

IF the UFH controller is expecting a low voltage or volt free contact, you cannot use that thermostat.

 

Both thermostat and wiring centre are from wunda so they must be compatible. From the instructions does 'SL' refer to switched L?

image.png.c0628dcfa9cb0566521f59e0aa2b5b7f.png

 

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Yep - that’s the “dumb” wiring centre from Wunda. 

 

Switched live - T4 - goes to the live on the board. The whole board goes live when the stat fires so it’s basically a way of controlling the boiler or pumps and the manifold actuators. 

 

How many zones  have you got..?

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3 hours ago, PeterW said:

Yep - that’s the “dumb” wiring centre from Wunda. 

 

Perfect then for me.

 

3 hours ago, PeterW said:

Switched live - T4 - goes to the live on the board. The whole board goes live when the stat fires so it’s basically a way of controlling the boiler or pumps and the manifold actuators. 

 

Ok, so L1, N1 use T3 and T4 o the thermostat back to the wiring centre. And the power (T2,T1) goes where - wiring centre also, or ?? Like I said, I am no electrician, but just need to know where to run the cables to/from! :S

 

3 hours ago, PeterW said:

How many zones  have you got..?

I will have 8 zones for the downstairs manifold with some rooms being covered by 1 zone.

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As it shows, you need a 3 core and earth cable from each thermostat to the wiring centre.

 

L on wiring centre to thermostat terminal 1

N on wiring centre to thermostat terminal 2

L1 on wiring centre to thermostat terminal 4

No connection to the thermostat terminal 3

 

That is it. Repeat for each room stat.

 

The wiring centre is providing power to each thermostat and reading it's output.

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1 hour ago, ProDave said:

As it shows, you need a 3 core and earth cable from each thermostat to the wiring centre.

 

Thanks Dave for s-p-e-l-l-i-n-g it out! Like I said, I just wanted to get it cabled in and then wait for the electrician to make the final connections. And he's evasive like a politician, so I have one final question. 😩

 

Can I get away with 1.0mm 3 core + E? Something like this? https://www.tlc-direct.co.uk/Products/CA1slash3G.html or a bit beefier like 1.5mm as suggested earlier by someone else?

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1mm is better. There is not much room in those wiring centres to get all the cables in, so the smaller the better.

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