UFH pump settings?

[Super_Paulie]

Before I turn on the UFH system for the first time, does anyone have any suggestions on what settings to run the Wilo pump on? I'll be honest, the curves etc mean nothing to me so any helpful advice would be awesome.

 

4 loops, 2 zones, 400m, 16mm Pex-al-Pex, biscuit mix between joist, Wilo Para pump as in the picture. Pipes tested at 5bar.

 

Thanks gents, much appreciated.

[ProDave]

It's pointless looking at graphs and doing sums.  Just try it, and aim to run it at the slowest (quietest) speed that will achieve the flow rate that you want.

 

Good pumps those nice and quiet.

[John Carroll]

Suggest the centre one, II, (constant pressure) there are three setting, i,ii & iii,, try ii for a start.

Edited April 4 by John Carroll

[Super_Paulie]

Thanks guys, I'll just have a play about. I have no idea what he curves are (the symbols) and what effect that would even have.

[Nickfromwales]

3 minutes ago, Super_Paulie said:

Thanks guys, I'll just have a play about. I have no idea what he curves are (the symbols) and what effect that would even have.

You can't do any harm, so just work out what the lowest setting is that will maintain the room temps. Biggest question you should be asking right now, is what temp to set the mixing valve to   Start off at 40^oC and go up each day in 2^oC increments until you are happy. Don't make adjustments in the same 24hr period, patience will pay dividends here  

[Nickfromwales]

 

[Super_Paulie]

Brilliant, cheers @Nickfromwales. That guy in the video is a man of little words...! Still not sure what the icons relate to all I'll do some research tonight.

I still need to get my biscuit mix in, that's next week's job, but I've commissioned all the UFH now and so far, no leaks 😆

Edited April 4 by Super_Paulie

[JohnMo]

1 hour ago, Nickfromwales said:

Start off at 40^oC and go up each day in 2^oC increments until you are happy

Or down 2 if you start to melt

[John Carroll]

The top icon (your pump, below) shows the pump in Constant Curve, CC, mode or better known in older pumps as constant speed, it has 3 settings, yours may be a 2M, 4.5M & 7M setting, corresponding to i,ii&iii, the higher the setting the greater the pump head and the greater the flow rate, its primarily used for radiators and sometimes UFH but the the second icon setting, Constant pressure or CP mode is generally recommended, the settings may be somewhat similar to the CC settings, the difference is that the pressure is held constant at whatever setting you set it to, the third icon shows Proportional Pressure or PP control where the pump head decreases with decreasing flow demand like rads fitted with TRVs, a example is my own, I have 8 rads on TRV control, I have the pump (Wilo Yonos Pico) set to PP 4.6M which gives me my required flowrate of 13LPM at a pump head of 3.5M, as the TRVs throttle down the pump (speed) and head reduce to ~ 2.8M resulting in reduced power consumption and no noise from the TRVs when well throttled down, power consumption varies from ~ 23 watts down to 14/16 watts.

Edited April 4 by John Carroll

[Super_Paulie]

22 minutes ago, John Carroll said:

The top icon (your pump, below) shows the pump in Constant Curve, CC, mode or better known in older pumps as constant speed, it has 3 settings, yours may be a 2M, 4.5M & 7M setting, corresponding to i,ii&iii, the higher the setting the greater the pump head and the greater the flow rate, its primarily used for radiators and sometimes UFH but the the second icon setting, Constant pressure or CP mode is generally recommended, the settings may be somewhat similar to the CC settings, the difference is that the pressure is held constant at whatever setting you set it to, the third icon shows Proportional Pressure or PP control where the pump head decreases with decreasing flow demand like rads fitted with TRVs, a example is my own, I have 8 rads on TRV control, I have the pump (Wilo Yonos Pico) set to PP 4.6M which gives me my required flowrate of 13LPM at a pump head of 3.5M, as the TRVs throttle down the pump (speed) and head reduce to ~ 2.8M resulting in reduced power consumption and no noise from the TRVs when well throttled down, power consumption varies from ~ 23 watts down to 14/16 watts.

Thanks a lot John, that's great knowledge and very welcome, appreciated.

Looks like CP mode will do the job and I'll play with the speed and flow to get what I need. All coming together nicely 👌

[Super_Paulie]

gunna be putting the biscuit mix down this weekend, anyone any thoughts on if i can run the system to speed up drying? i mean its a dry mix but will obviously have water in from the building sand. As its only acting as a thermal mass can i speed up the drying time or should i just sit it out for the next few weeks?

[SteamyTea]

15 hours ago, Super_Paulie said:

can i speed up the drying time or should i just sit it out for the next few weeks

Sit it out.

It does not dry via evaporation, it cures via a multistage chemical reaction.  Part of that reaction generates heat that starts another part of the reaction.  If you skip one stage, the mix does not react correctly.

[Super_Paulie]

3 minutes ago, SteamyTea said:

Sit it out.

It does not dry via evaporation, it cures via a multistage chemical reaction.  Part of that reaction generates heat that starts another part of the reaction.  If you skip one stage, the mix does not react correctly.

 

Even on a 8-1 dry mix? Plenty to do in the meantime, but it would be nice to just crack on.

[SteamyTea]

1 minute ago, Super_Paulie said:

Even on a 8-1 dry mix

More so as it uses, in part, atmospheric moisture.

 

There seems to be a myth that cement mixes are simple, mix up the components, pour and tamp into the right place, then speed up the drying.

The chemistry is much more complicated.

[John Carroll]

What kind of manifold flow temperature?.

[Super_Paulie]

Can go as low as 35 with my mixer. As it's just biscuit for thermal mass I don't need it to be structural, hence the 8-1 dry mix.

[saveasteading]

16 hours ago, Super_Paulie said:

i can run the system to speed up drying? 

You can but you really shouldn't.

You should cover it with plastic sheeting to keep the water IN for a few days. This allows the chemistry to take place.

If you mix with water quantities  according to the instructions then most is taken up in the chemical reaction. The rest will evaporate in 2 weeks of normal spring temperatures.

If you speed the water evaporation it will weaken the screed.

 

[Super_Paulie]

Water quantity is only what is in the sand on delivery, it's a dry mix. It will serve no structural purposes, it's thermal mass only.

[John Carroll]

Whatever about the thermal mix. would suggest CPi setting at 3M initially, 3M (2.8) should be sufficient to circulate 3.0LPM through each 100M loop, total 12.0LPM, 0.72m3/hr, as long as there is a bit of adjustment left in the (max) flow loop regulator then its fine, if not, go to CPii, 5M setting. In practice, the flow requirement will probably be less than 3.0LPM/loop.

 

"4 loops, 2 zones, 400m, 16mm Pex-al-Pex, biscuit mix between joist, Wilo Para pump as in the picture. Pipes tested at 5bar."

[SteamyTea]

6 hours ago, Super_Paulie said:

it's thermal mass

Thermal Inertia or Thermal Diffusivity if you please.

[Super_Paulie]

Whatever floats your boat! Either way it's not a structural screed. However it'll take me a week to get it down so the start might be dry by time I've finished anyways.