Auto air vent

[Dan Masey]

My system boiler is above my unvented cylinder so would I need a Auto Air Vent just above the primary flow to the cylinder? Iv been to 2 call outs this week with AAV leaking. My cylinders in the loft so would sooner not.

Thanks.

 

[WHPES]

You need an AAV at the highest point, wherever that is.

Flamco air vents have a good cap you can screw down and seal once it is bled.

Keep the system free from sludge and debris and the air vent will last longer.

 

[Alanc]

small tundish into overflow, saves the ceiling in a few years.

 

[ed209]

Why would you seal a AAV it stops them functioning for there purpose might as well just fit manual bleed valve

 

[ed209]

Saying that I must confess to screwing some down myself

 

[pipefitter]

Once the system is fully bled I always close the aav's ,otherwise over time they start to leak

 

[mountainman]

Once the system is fully bled I always close the aav's ,otherwise over time they start to leak

If you do that then its no longer an automatic air vent, defeats the object imo.

 

[Dan Masey]

so is it worth putting one on the flow to the cylinder or no?

 

[SafeGasInstall]

just fit manual ones on flow and return , when fill up bleed air then put inhibitor and job done

 

[SafeGasInstall]

i would have had a frame made for the UHWC , as when full with water will be like 250kg

 

[SafeGasInstall]

stop install and make big frame to spread the weight !!!!

 

[ed209]

Might also be worth considering a tray for it to stand in with overflow, I know at least one cylinder manufacture makes one think it might be "Range"
Seem to come across quite a few with leaks from various places

 

[ed209]

http://www.cylindertray.co.uk/

 

[Dan Masey]

The floor is all supported an joists doubled up. There is a concrete wall below it.

 

[pipefitter]

If you do that then its no longer an automatic air vent, defeats the object imo.

Yeh I realise what you saying , I leave them open for as long as needed ,once I know all the air is out I shut them off ,sometimes a week later,otherwise you will be replacing aav's a year down the road
Even the aav in a boiler should be closed when venting is complete

 

[mountainman]

Even the aav in a boiler should be closed when venting is complete

I accept what you're saying in a practical sense but I don't think that the boiler MI's state that.

 

[pipefitter]

No probably not ,just my opinion ...

 

[lame plumber]

r u gas safe dan? if not tsk tsk

 

[Dan Masey]

Nope not gas safe. That's why I'm not fitting the boiler only my megaflo. And yes I'm part G qualified before everyone starts going mad lol

 

[SafeGasInstall]

so who is piping the boiler and fitted the flue already

 

[SafeGasInstall]

View attachment 13725 so is it worth putting one on the flow to the cylinder or no?

what is the fitting between the combine NRV+PRV and the cold water inlet point to megaflow

 

[mcniven]

Iv had a horrible time today getting air out a simular system

System drained, refilled bled all rads etc, boiler kept cutting off, bled pump etc it was altho the pump had tons and tons of air was takin ages to release water and was constantly spouting

The screw air vents primary flow manual ones forever opening and closing AAV are a massive time saver

 

[SafeGasInstall]

Iv had a horrible time today getting air out a simular system

System drained, refilled bled all rads etc, boiler kept cutting off, bled pump etc it was altho the pump had tons and tons of air was takin ages to release water and was constantly spouting

The screw air vents primary flow manual ones forever opening and closing AAV are a massive time saver

i would have run it on hw only and air would have come out in 5min

 

[SimonG]

I find aav's leak when over exposed to heat. The closer to the boiler/heat source the less time they last.

 

[Dan Masey]

My local gas safe engineer. He'll be back once the cylinder is fitted and he'll continue from the 2 port valves with the gas run.

 

[Dan Masey]

what is the fitting between the combine NRV+PRV and the cold water inlet point to megaflow

8 bar pressure relief valve.

 

[SafeGasInstall]

8 bar pressure relief valve.

8 bar valve has build in nrv ! I am after what is after that as i can not see on your picture

 

[Dan Masey]

That's for the filling loop.

 

[jase158]

Honeywell say aav is only for filling up, not for leaving open. they leak when you put inhibitor in system too

 

[lame plumber]

Honeywell say aav is only for filling up, not for leaving open. they leak when you put inhibitor in system too

so a standard rad valve would do the job just as well and save money aka intergas boilers 🙂

 

[jase158]

so a standard rad valve would do the job just as well and save money aka intergas boilers 🙂

if the vent is at the highest point of the system

 

[SafeGasInstall]

so a standard rad valve would do the job just as well and save money aka intergas boilers 🙂

me always fit manual vents to pressurised systems and auto vents to open vent