micro bore airlock

[ambrosia]

micro bore system

boiler is down stairs
ho****er cylinder, air separator, pump and zone valve are in the loft conversion, f and e tank is directly above

went 2 weeks ago and found a massive airlock at the top which had completely starved the pump of water, big section of pipework from the feed pipe to below the pump was totally dry

no work had been done on the system, thought it was vey strange that an airlock had suddenly appeared, couldnt figure out where it had come from, checked float valve in the f and e, checked rads for air etc, thought if it had a leak why wouldnt the system simply fill up again with water not air. had no idea where it was drawing this air from

sucked the airlock out with a wet vac put in new pump and put it down to just one of those things, however got to return tomorrow morning as apparently its happened again

feed and vent
old pump and air seperator

didnt take any other pics as i wasnt expecting to be going back

 

[Chalked]

Might be worth cutting the feed out to see if there's a blockage.

 

[SimonG]

Sure it was air and not hydrogen?

 

[diamondgas]

If the boiler permits I'd close couple the f&v or better still up the f&e tank connection to 22mm and run the vent straight in as combined f&v. These little air seps are prone to pumping over/surging, in my experience. Once you've sorted that out I'd be wondering how bad the system could be blocked up if it has been pumping over or surging?

 

[Ch4 plumbing]

Id start by cutting the Ballafix valve out of the feed/expansion pipe, that's just asking to block up!
I take it you closed it to change pump and then reopened it?

 

[ADM360]

I look at a possible blockage where the feed pipe connects into the primary's

 

[ADM360]

you not meant to have any form of isolation on the feed pipe to an open vent system!

 

[ambrosia]

I look at a possible blockage where the feed pipe connects into the primary's

I did take the surrounding pipework apart, from the pump to that ballofix and including the air sepertaror, I also openned the ballofix while it was apart to check the above pipework. All seemed okay

Sure it was air and not hydrogen?

it could have been hydrogen the 1st time but if its gone again within a week it wouldnt have built-up so quickly

run the vent straight in as combined f&v

I could give that a try

Id start by cutting the Ballafix valve out of the feed/expansion pipe, that's just asking to block up!
I take it you closed it to change pump and then reopened it?

yeah I isolated the f and e tank from there while I was working on it and no I didnt cut it out when I recommissioned everything, bt now I wish i did

Thanks for all your suggestions guys, I'll let you know what happens when I go back

 

[ambrosia]

thanks guys

went back today, which was odd if you have no heating and hot water you'd think they'd want me back ASAP

found the heating and hot water to be working, only problem was the new tenant didnt know how to use the timer and heating was coming on at the wrong times, absolutely nothing to do with the original problem, happy days

but never the less thanks guys for all your sugestions and help, as always much appreciated