Air lock in underfloor heating

[Paul Cockhill]

Hi

Can anyone tell me the best way to purge the air from a speedfit underfloor heating system. I thought the best way was through the pump but would like any suggestions.

Many thanks

Paul

 

[PlumbBobBob]

what about a wet and dry vacuum to pull it through.

 

[unguided1]

was there not any installation or commisioning manual with it because it will tell you in there

 

[micketherton]

Have you had any luck yet? I have just posted a similar question this morning!

 

[danielp]

could connect a hose on to the inlet and outlet of the run from the manifold and wait till you stop seeing bubbles come out

 

[josh]

You should always prime all your underfloor heating loops by connecting a hose to the top of the manifold and another hose to the return half of the manifold going outside/to a drain and using the isolation valves run water through each loop one until water is flowing freely then once all loops are running freely open all the loops up and let water run through for a min until is all freely running.
(do this with the manifold isolated from the heating system obviously)
done this hundreds of times and never had any problems but have heard of similar problems like this, and normally is simply cos the plumber hasn't primed it as said above.

 

[micketherton]

You should always prime all your underfloor heating loops by connecting a hose to the top of the manifold and another hose to the return half of the manifold going outside/to a drain and using the isolation valves run water through each loop one until water is flowing freely then once all loops are running freely open all the loops up and let water run through for a min until is all freely running.
(do this with the manifold isolated from the heating system obviously)
done this hundreds of times and never had any problems but have heard of similar problems like this, and normally is simply cos the plumber hasn't primed it as said above.

Many thanks for this advice. It is very useful, as I did not want to cut the pipes to put air bleed valves in at the highest point of each loop. cheers

 

[JG123]

We would normally pull it through with the power flusher or solar pump.

 

[stevetheplumber]

never realy had an airlock in underfloor or anything else thats mains filled if its under screed it should have been filled and pumped up before pouring

 

[mitchellplumber]

I've just installed a speed fit underfloor heating system in with a bio mass burner and accumulator tank. Had same problem, although under-floor heating was pre-pressurised before screed. When system was filled, the under-floor heating loops were air-locked. Switched both flow and return valves off at manifold (pump side) put mains hose onto flow side of manifold. Drain hose on to return side. Flush mains water through each loop one at a time. And touch wood, no problems so far. First time using speed-fit underfloor heating and so far so good.

 

[micketherton]

Hello All, fixed my heating yesterday! lovely and toastie!!! The problem was I hadn't realised that the flowmeters I had on the supply Reliance manifold were also adjustable restrictor valves!. ...which were turned in/off. I assumed that the loop control was with the return manifold valves only. Ther were no clear instructions, and I couldn't find any specific references to this on the web. I used mains pressure to the inlet manifold to clear the purge the loops, very important as the loops go up 3 floors with no air bleed points! Waited until there were no bubbles out of the bucket from each of the 7 return loops in manifold in turn. All up and running with my combi lovely! thanks all