Floor Probes

[MortarThePoint]

I've been getting my bits from WUNDA and wondered ( ? ) if their floor probes (aka Thermostat sensor) are any good? Being something that gets cast into the screed I can't change my mind later.

 

Also, in terms of placement within the room. Should they be placed near the start of a floors circuit (B) or mid circuit (A)? Near the start makes sense to me as the purpose of the sensor is to protect floor finishes and so the hottest point needs to be detected, but I may be missing something.

 

Finally, I also assume that the Thermostats can only take one temperature sensor input.

 

@Nickfromwales Is the doctor in session?

 

 

[PeterW]

Only tend to use them in wet room floors. 

[dpmiller]

you don't cast them in, you cast in a short length of pipe with a closed end (or similar) and feed the prove into this thermopocket.

[MortarThePoint]

6 minutes ago, dpmiller said:

you don't cast them in, you cast in a short length of pipe with a closed end (or similar) and feed the prove into this thermopocket.

 

Cool, that allows fixing them if they break which is good. Can you recommend a type of pipe to use?

[Onoff]

See the lone, 16mm, pex-al-pex  pipe with the taped over end, thats where my floor probe runs to:

 

 

Peter gave it to me years ago...it's still not connected to anything but then neither is the UFH!

[dpmiller]

just a bit of your UFH pipe crimped flat at the end will do

[Onoff]

Mine comes up through the slab and exits just outside the bathroom in what is now a slim services "cupboard":

 

 

[MortarThePoint]

9 minutes ago, Onoff said:

See the lone, 16mm, pex-al-pex  pipe with the taped over end, thats where my floor probe runs to:

 

 

Peter gave it to me years ago...it's still not connected to anything but then neither is the UFH!

 

Easy when you know how!

 

I'll have to avoid crossing  over like you have as I don't have the mesh, but where I have serpentine pattern I can just go between two loops.

 

I see you have put your sensor at the hottest point (B from my original post)

Edited July 30, 2021 by MortarThePoint

[MortarThePoint]

52 minutes ago, Onoff said:

Mine comes up through the slab and exits just outside the bathroom in what is now a slim services "cupboard":

 

 

 

Looks good and very neat PIR insulation

[Onoff]

55 minutes ago, MortarThePoint said:

 

Looks good and very neat PIR insulation

 

Just a pity it's not all connected and working! ? SWMBO seems to have a mental block on me now digging up the adjacent room in the last photo.

 

 

 

 

 

 

[MikeSharp01]

In addition to one under the slab, in the ground to all intents, and a couple in the middle of the zones I placed one sensor, pocket pipes anyway, In the floor about 1m back from the windows. It struck me that I might like to know if the sun is doing its job before it gets ahead of us and to allow me to move heat from zones getting sun to zones not getting sun. I swither about this being a good idea or not, when I put them in I am sure I had a way of determining a control schema but I cannot for the life of me find my notes and right now, in response to this thread, I am struggling to work out what the plan was.

[Nickfromwales]

On 30/07/2021 at 19:15, MikeSharp01 said:

In addition to one under the slab, in the ground to all intents, and a couple in the middle of the zones I placed one sensor, pocket pipes anyway, In the floor about 1m back from the windows. It struck me that I might like to know if the sun is doing its job before it gets ahead of us and to allow me to move heat from zones getting sun to zones not getting sun. I swither about this being a good idea or not, when I put them in I am sure I had a way of determining a control schema but I cannot for the life of me find my notes and right now, in response to this thread, I am struggling to work out what the plan was.

Things like this usually get added to the growing stack of "good ideas", and fall to the wayside when you realise that life is too short to worry about things as minor ( even more so when there is an ever-growing list of things far more major to tend to ).....

A good idea to put the offcut UFH pipes in as conduits, and simply run them to a single back box with a blank plate on, and a Cat 5/6 back to a plant / data location for 'Justin'.

[Temp]

Most stats use something like a 10K Ohm NTC probe. These are readily available for a £few so you don't really need to spend silly money for the ones from the UFH company if you decide to buy spares.

[MortarThePoint]

I've been thinking about embedding some DS18B20 temperature sensors on a network. They're about £4 each. Fakes are much cheaper (~50p) but cause issues which is a shame as at 50p a pop I'd litter them everywhere.

 

https://create.arduino.cc/projecthub/TheGadgetBoy/ds18b20-digital-temperature-sensor-and-arduino-9cc806

Edited August 2, 2021 by MortarThePoint

[Fallingditch]

On 02/08/2021 at 11:31, Temp said:

Most stats use something like a 10K Ohm NTC probe. These are readily available for a £few so you don't really need to spend silly money for the ones from the UFH company if you decide to buy spares.

any idea where to source longer (say 8m) 10k NTC sensors please?

[JohnMo]

I bought a remote probe, thought it was a good idea at the time.  Found in a box the other day - full of other good ideas at the time. Where I was going to install I removed the thermostat, didn't need it.

 

Do you need them - no, unless you embed as a high temp cut off to protect a delicate floor covering.

[Radian]

On 02/08/2021 at 14:08, MortarThePoint said:

They're about £4 each. Fakes are much cheaper (~50p) but cause issues which is a shame as at 50p a pop I'd litter them everywhere.

 

It's a minefield for sure. How to spot a fake DS18B20

[dpmiller]

8 hours ago, Fallingditch said:

any idea where to source longer (say 8m) 10k NTC sensors please?

 

NTC sensor + 8m of cable = profit.

 

/ in other words, just extend the cable...

[Temp]

+1

I wired up my own. Cable cost way more than the actual NTC. Encapsulated 10k NTC with short cables are five for £7.50 on Amazon.

 

Google found these but I've never purchased from these companies... 

 

Various lengths Inc 10m for £15..

https://www.ebay.co.uk/itm/183331715037?chn=ps&mkevt=1&mkcid=28&var=690639609095

 

 

10m for £21..

https://www.justradiators.co.uk/thermosphere-floor-sensor-probe?ps=MjQ5PTE1MzUx&gclid=Cj0KCQiA9YugBhCZARIsAACXxeLok7yVFEa2erOpxJCsXUTmaseUfl25MJ21u-PweOzb6tuTduS6CBAaAmCbEALw_wcB#249=15351&utm_term=&utm_campaign=Shoptimised+|+Incremental+|+Performance+Max&utm_source=adwords&utm_medium=ppc&hsa_acc=5690114029&hsa_cam=19604440538&hsa_grp=&hsa_ad=&hsa_src=x&hsa_tgt=&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3

 

 

 

 

[SteamyTea]

11 hours ago, Radian said:

It's a minefield for sure. How to spot a fake DS18B20

Yes, but not as much as trying to find a website that gives the correct advice.

Seems every site has a different opinion about how to spot a fake.

 

I just buy them, then calibrate them to see if the readings are sensible.