Megaflo regenerate air gap?

[Unclehr]

Hi all,

Megaflo 300i in the loft. I noticed the overflow was dripping and also the tundish. 10 second google and lots of instructions how an average user (I'm very average) can recharge the air gap. Followed to the letter:
Closed mains feed to megaflo
Opened lowest hot tap. It drained pretty quickly.
Opened TRV (actually called T&P release valve)

At that point nothing happens - no water flow through tundish, and no gurgling.

Put all back on and it's not dripping but as I didn't really do anything, it can't be fixed can it?

Shall I just leave it till it goes again or is this impending doom?

Thanks for any advice

 

[Chuck]

Opened TRV (actually called T&P release valve)

You need to grip it, turn in anticlockwise enough that it opens and starts sucking, and then keep it like that for about 10-20 minutes. If you turn too far (more than about 30° IIRC) it'll clunk shut again.

I suggest you wear a thick working glove on the hand you use to hold the valve open because the spring is pretty strong and otherwise, unless you have plumbers' fingers, you'll be in quite a lot of pain by the time you've finished.

 

[Unclehr]

Thanks Chuck. It was pretty easy to turn and stayed in the turned position - does that suggest the spring is a bit knackered?

I checked what work was done on the system and in 2019 it had a new TPRV at least that's what the job sheet says, so it should be OK

 

[Scott_D]

Is it a horizontal cylinder with connections on the highest part ?

 

[Unclehr]

Hi Scott, No it's normal vertical but I did it again following what Chuck said and turns out I was a bit limp when turning the valve. It needed a good hard grip. And now my hand hurts after 15 mins+ of holding it so looks like it worked! thanks.