UFH Manifold "Letting By"

[Trw144]

Is it normal for UFH manifold to "let by" a little bit sometimes (ie small flow rate even if actuator is nt open). My kitchen floor feels like the UFH has been on during the night, even though I m pretty sure there was nt a call for heat (there was elsewhere so the manifold would have hot water to it)?

 

I have the plumber coming by in the morning to flush two circuits where we seem to have air stopping any flow, can get him to look at anything else that might need sorting to.

 

[Nickfromwales]

8 minutes ago, Trw144 said:

Is it normal for UFH manifold to "let by" a little bit sometimes (ie small flow rate even if actuator is nt open). My kitchen floor feels like the UFH has been on during the night, even though I m pretty sure there was nt a call for heat (there was elsewhere so the manifold would have hot water to it)?

 

I have the plumber coming by in the morning to flush two circuits where we seem to have air stopping any flow, can get him to look at anything else that might need sorting to.

 

Just remove and refit the actuator head / s for the kitchen as sometimes if not fitted / seated properly ( fully down ) they could allow very slight flow. You don't need much flow to get detectable heat in a well insulated slab BUT if there are two actuators and two loops in there I'd say there's more to it, like controls / programming etc. 

Edited November 26, 2017 by Nickfromwales

[Trw144]

@Nickfromwales well I did wonder if one of the loops isnt allocated to the right actuator, but they are off different manifolds.

 

Downstairs my office is nt getting warm - I suspect it never has as it was only two months ago we emptied the storage boxes out of it and started using it, so it's the first time I have used the heating in their.

 

Upstairs, I have one bedroom that is nt getting warm (I m sure it was ok last year) so again am assuming its air.

 

I might switch all the circuits on tonight so everything is open and see if they heat up then just to rule it out.

[Nickfromwales]

Switch all of the stats off bar the kitchen and see what gets / stays warm. That's the quickest way. Switching everything on wont show divisibility / correct allocation . Once that's done switch the stats on one at a time as heating a zone that's cold is the quickest way to see what's what IMO. 

 

Edit : do you have a digital laser thermometer ?

[Trw144]

@Nickfromwales I was thinking that if I turn everything on, and it doesn't get hot then it must be air?

 

I have a laser temp sensor at work somewhere - it can be quite tricky determining if the ufh has been on, especially on the wooden floor upstairs 

[PeterW]

It could just be poor flow set up. 

 

I would make sure you have a good 3 bar in the system and close all the actuators or remove them. Then run the pump at full speed to clear the air from the circuits one by one as it may take some time. Have you got an auto vent somewhere high up in the system ..?

 

I’d look to clear the air from the circuits one at a time - even the good ones - and then go back to putting the actuators on. 

 

Who balanced the flows on the manifold ..?

 

[Nickfromwales]

5 minutes ago, Trw144 said:

@Nickfromwales I was thinking that if I turn everything on, and it doesn't get hot then it must be air?

 

I have a laser temp sensor at work somewhere - it can be quite tricky determining if the ufh has been on, especially on the wooden floor upstairs 

Possibly, but if you turn on one zone at a time then then 100% of the pump potential is sent to that zone so any air may get forced through a bit more effectively. Do you have flow gauges on each loop ? With everything open the pump potential is divided . 

[Trw144]

4 minutes ago, PeterW said:

It could just be poor flow set up. 

 

I would make sure you have a good 3 bar in the system and close all the actuators or remove them. Then run the pump at full speed to clear the air from the circuits one by one as it may take some time. Have you got an auto vent somewhere high up in the system ..?

 

I’d look to clear the air from the circuits one at a time - even the good ones - and then go back to putting the actuators on. 

 

Who balanced the flows on the manifold ..?

 

 

I ve tried running just these one circuit on their own and still not getting hot so don't think it can be flow settings. The plumber set flow settings - is it worth resetting them all tomorrow after he has flushed it and start over again?

[Trw144]

@Nickfromwales Nick, what does this button do on the back on the actuator - i don't think it's a swap between normally open and close but the ones with it pressed on look like the pin is slightly further protruding?

 

Its pushed in on one or two (not corresponding to circuits with problem though)

Edited November 26, 2017 by Trw144

[Trw144]

Is this what could be letting the trickle past?

Edited November 26, 2017 by Trw144

[Nickfromwales]

Haven't ever seen that before TBH. Is it part of the locking mechanism or is it deffo altering the position of the pin ?

If the latter, changed them all to the fully recessed position and try again. 

Can you post a link / Google the manufacturers blurb?

[Trw144]

@Nickfromwales it's one of these .....

 

https://uk.giacomini.com/sites/giacomini.uk/files/Giacomini R473 Actuators_Data Sheet.pdf

 

 

[dpmiller]

so the red button locks the actuator Open.

[Trw144]

@Nickfromwales

So, been out all day at a kids party, just got back and had a chance to take a closer look. Have adjusted all the actuators so they all have the button pressed in - basically it's like a bleed valve for bypassing. Explains why the kitchen floor was always warm.

 

Moving onto the rooms without heat - I think it may be flow rate as I ve managed to adjust the valve so I am showing a flow, so presumably it can't be an air blockage. The manifolds I have have two elements to the balancing - I ve done the adjustment I can but did nt want to risk attacking it with an adjustable spanner on a Sunday evening - will see if it has helped and will get plumber to run through the balancing  when he is here in the morning.

[Nickfromwales]

The flow gauges don't usually turn out more than 2 revolutions . Any more than that and your off to Wellies R Us ?

[Trw144]

@Nickfromwales Yep that's what I feared. The ones I have have an Allen key adjustment in the middle, with a nut on the outside for bigger adjustment. I ve done the fine adjustment for now and will run through them again tomorrow.

 

I should know if at working shortly - have these circuits now on.

Edited November 26, 2017 by Trw144

[Nickfromwales]

1 hour ago, Trw144 said:

@Nickfromwales Yep that's what I feared. The ones I have have an Allen key adjustment in the middle, with a nut on the outside for bigger adjustment. I ve done the fine adjustment for now and will run through them again tomorrow.

 

I should know if at working shortly - have these circuits now on.

You should only balance when every loop / actuator is fully open. I'm guessing you know that.