UFH Pressure Test Length / Pressure Dropping

[jamesmonk83]

I would have just typed no, but forum rules prevent less than 5 word answers.

Ah hopefully you're onto something, so is there a rule of thumb for how long as a minimum we should run it for before you can sure all the air is out?

 

[SimonG]

Ah hopefully you're onto something, so is there a rule of thumb for how long as a minimum we should run it for before you can sure all the air is out?

Not really, depends on how flat you've managed to get the pipe, flow rate of your mains etc. Best to run longer than shorter.

Also if this fixes it and you go ahead on the screed, don't be alarmed when the pressure increases due to the heat out of the screed.

 

[jamesmonk83]

Not really, depends on how flat you've managed to get the pipe, flow rate of your mains etc. Best to run longer than shorter.

Also if this fixes it and you go ahead on the screed, don't be alarmed when the pressure increases due to the heat out of the screed.

Okay thanks, we'll give that a go and report back if it fixes it.

The manufacturer did warn about the pressure/heat from the screed but will definitely keep an eye on it.

Thanks again for the help.

James

Not really, depends on how flat you've managed to get the pipe, flow rate of your mains etc. Best to run longer than shorter.

Also if this fixes it and you go ahead on the screed, don't be alarmed when the pressure increases due to the heat out of the screed.

Sorry just one more thing, assuming there is still air in the system would this cause the pressure to drop then?

 

[centralheatking]

Where is the aav even if its a temporary one ?chking

 

[SimonG]

If there's air in the system then yes the pressure can drop.

If anything else you would have water everywhere.

 

[jamesmonk83]

Where is the aav even if its a temporary one ?chking

Is that the white plastic thing on top of the drain/fill valve that you can change using a flat head screwdriver? I've not gone near that so it will be in how it was supplied by the manufacturer.

Is there any benefit in getting an auto one over a manual one or is this something a plumber will sort out when everything is connected up to the boiler/pump etc?

If there's air in the system then yes the pressure can drop.

If anything else you would have water everywhere.

Okay that's good to know thanks.

 

[centralheatking]

Is that the white plastic thing on top of the drain/fill valve that you can change using a flat head screwdriver? I've not gone near that so it will be in how it was supplied by the manufacturer.

Is there any benefit in getting an auto one over a manual one or is this something a plumber will sort out when everything is connected up to the boiler/pump etc?




Okay that's good to know thanks.

send a picture this will help a lot chking

 

[jamesmonk83]

send a picture this will help a lot chking

I don't have a decent front on photo at the moment (we don't live at the property) but these are the fill/drain valves on the system - Manifold fill/drain valve pair

Would there be any benefit in getting something like this instead - Manifold fill/drain valve pair with auto air vent

 

[centralheatking]

I don't have a decent front on photo at the moment (we don't live at the property) but these are the fill/drain valves on the system - Manifold fill/drain valve pair

Would there be any benefit in getting something like this instead - Manifold fill/drain valve pair with auto air vent

They are very simple manual radiator bleed valves, you most certainly should have opened them till water appeared then closed them and done the same operation plenty of times. I know a little about UFH but much about principles it looks like mickey mouse stuff in my opinion Chking

 

[townfanjon]

It's a Rothenberger RP30 pump.

I know its a long shot but are you relying on the pressure tester valve to close off the system or are you isolating it through an additional valve / lever arm .

 

[jamesmonk83]

I know its a long shot but are you relying on the pressure tester valve to close off the system or are you isolating it through an additional valve / lever arm .

We've tried both the drain valve on the system and the pressure tester valve but it doesn't seem to make any difference, the pressure still drops either way.

They are very simple manual radiator bleed valves, you most certainly should have opened them till water appeared then closed them and done the same operation plenty of times. I know a little about UFH but much about principles it looks like mickey mouse stuff in my opinion Chking

Okay thanks for clearing that up, I'm a little reluctant to start altering them as the manufacturers written and video instructions doesn't mention doing anything to them during the installation/setup process.