UFH heating advice

[HomeAutomation666]

Trying to understand what is happening with my UFH and also if my logic is correct.

3 bed flat, Lounge and 2 bedroom upstairs 700 Sqft - 1 bedroom downstairs 300 sqft (guess)
UFH was working, but one room was always cold, over the summer had some pipes moved and then heating didnt work


Centralised Hot Water system
The heat pump is all controlled by Eon (but taken cover off)
The pump is grundfos alpha2 l 15-40
The UFH is polypipe

What i did
Refilled system
Depressure Manifold
Took off Flow Meter and made sure working
For each circuit (4) put the flow meter to 1 L/M as when higher the room didnt get hotter



State
I now have the flat warm finally but its taken days, and i was getting 0.1 degree increase an hour in the rooms (but this may have been from zero as no water in system before i started)
The water coming in from the flat is very hot on the pipe, the water into the manifold was 24c but seems to increase as the rooms get hotter (but floors dont feel warm)
The Grunfos system when you turn on defaults to 1 but manual says it should be on setting 3 for UFH at which point the flow meters jump, however in the 10yrs in the flat ive never changed it

Questions
Have i got an airlock, the water isnt hot enough under the floor or a flow rate issue?
Is the Grundfos on the right setting? If i changed this then im guessing more flow = most cost and if the water isnt hot enough for the flow im just pushing cold water through?
Everything ive read says that UFH should be set to 1 L/M i presume this is per circuit?, i dont really see how i can accurately adjust this between 0 and 1 on a float to balance the system.
What is the black RAVK valve doing?
There is a adjuster to right of the Grundos that seems to do nothing
There is a valve near the Thermostat that has the temp of the water going into the thermostat - not sure what that does either.

Also is it possible the system was just so cold its taken this long to get heat through it all? Obviously want the house to be warm but would like to not bankrupt myself in the process

Thanks for the advice

 

[Johntheo5]

That 4M pump setting on PP1 (proportional pressure) is not suitable for UFH. change the setting to (constant pressure) CP1, (2.4M) third LED from the left and set your flowmeters to 2.0 to 2.5LPM, if you can't achieve this, change the pump setting to CP2, (3.0M) fourth LED from left and see how you get on. Have you got flow/return thermometers on the manifold?

 

[HomeAutomation666]

Right ok so as per the manual

Ive never changed the setting on the pump and it goes back to default after power off so probably been set like that for 7yrs - no wonder it always felt crap

Reason i set the flow to 1 M/L is that is what the internet said for a UFH on Heat Pump? I presume what was happening when the setting was a PP1 and Flow at 2/3 M/L is that the water was getting pushed through before it was hot?

Presume whacking that to constant overrides that and will just allow more pressure and therefore i can increase the flow higher? Does this also mean more water and therefore a significant cost increase?

Yes have just got flow meters on manifold but exceeded file size - 4 x all set to 1 M/L now

The only thermostat is the 5th Pic Termax and it is on the pipe pre manifold

Thanks so much

 

[Johntheo5]

What is the Heat Pump flow temperature?, if its too low then the UFH TMV may not work properly, what is the TMV set to? the more water water you push through any system whether it be a radiator or a UFH loop, the greater the heat output as the mean rad temperature or UFH loop temperature is higher so will emit more heat.
Yes, of course there is a cost, if your system was only producing say 1 kw and your require say 6kw and you get the system to produce this then the heat/cost has to come from somewhere?.

 

[HomeAutomation666]

Havent got a way of measuring the temp - but the pipe coming in from the central system is hot to touch and the pipe to manifold is warm

Ok i will change the Grundos to setting 3 and increase the Flow Rate to 2 and see what happens

Thoughts on the Auto Balancing Actuators?

 

[Johntheo5]

If the pipe to the manifold is just warm then you may not get much heat output, you probably need a minimum of 35/38c.

Don,t see any need for auto balancers, once you have set up your flow rates manually with the pump in CP mode, why should they then change?

 

[HomeAutomation666]

Ok thanks

I can an issue with 1 of the flow meters Polypipe UFH Manifold Flow Meter PB127FM

I presume there is nothing special about the flow meters and i can just replace them with something like the below?

https://www.amazon.co.uk/Underfloor-Heating-Manifold-Meter-Regulator/dp/B076NTGMWN/ref=asc_df_B076NTGMWN?mcid=7124a2626adc313f98461e562a415edd&tag=googshopuk-21&linkCode=df0&hvadid=697339313978&hvpos=&hvnetw=g&hvrand=11052905585558893915&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9222618&hvtargid=pla-420456065226&psc=1&gad_source=1

 

[HomeAutomation666]

If the pipe to the manifold is just warm then you may not get much heat output, you probably need a minimum of 35/38c.

Don,t see any need for auto balancers, once you have set up your flow rates manually with the pump in CP mode, why should they then change?

Set it back to 1 temp - However still getting no heat through, the actuators are warm, but the supply and flow pipes are stone cold and the Pipe thermostat into the Manifold is reading at about 18c

Do you know what the + - valve on the right of the pump is likely to be and controlling is the the mixer or the release valve maybe?.. I have tried turning it fully to + and i can either hear water or air, however turning it back a few turns and the sound disapears

 

[HomeAutomation666]

This is the system

https://assets.danfoss.com/documents/353645/AQ082486478026en-010501.pdf

I presume it is the mixing valve as per 6.2.1 IHPT 90 controller (45–65 °) and therefore i have set to the fully - position and then turned towards + 5 times to get to 48c which i presume is what i should of done