Guess what woke wife at 6AM - no the Pump screeching! HELP!

[cardob00]

Have a Potterton Netaheat 22 boiler - working fine as far as I know. Have a mini tank in loft for CH etc. Few months back started getting gurgling noises from boiler, figured air in system so bleed rads which resolved for a bit.

Meanwhile, upstair (loft room) rad was turned down (half way) as we don't the room much. After a while the top of the rad was cold so opened the rad fully. However, still cold on top. After 2 weeks entire rad was cold, despite bleeding every few days air seems to collect in it still! I am able to removed the valve completely with NO WATER coming out...so presume it's sludge in it..perhaps due to turning down - wish i hadn't now? Any help on this? Do I need to get a proff in to remove the rad and replace or clear it?

Then this morning, we were woken with a screeching noise that wife said seemed to come from boiler - I checked and seemed to be coming from the pump....decided to turn off in case. Then thought..hmm haven't bleed that rad upstairs for a while and did this along with bathroom rad. I think I turned off and on pump (Grundfos) using the switch that I can't see (as it's against a wall)! and put heating on. everything seems to work...all rads that were working are ok (no loft one still isn't) and no screeching noises so far for last 6 hours...

So....should I be worried about this screeching noise in the morning...could an airlock produce this noise from a pump?

(sorry about the lenght of this post...I'm verbose and can't help it)

 

[JPC]

have u checked the f and e tank in the loft. poss it has no water in it and ball valve is stuck closed.

 

[cardob00]

Thanks for the super fast response Jamie...but f & e tank I assume (sorry yes I am Stupid!) is the small feed tank for the CH right?

So you think the pump screechin is air lock in pump (which is now gone)? Almost sounded like a rotar blade turning against metal..but may be that is an airlock - never heard something like that....

ta

 

[JPC]

yes the f and e is the -feed and expansion tank....it feeds water to the C/H system and allows it to expand back up when the water heats up....hence f and e.

it could have dried out ?
u could have blockage.
someone might have fitted a valve on that pipe and been closed !? (the down pipe from the bottom of the f and e .
a screeching pump (and overheating) normally would be lack of water.
u should have water in all rads below the f and e (as it works by gravity)...
is ur loft rad below the f and e level.
as stated above...check the water supply is ok.
the ball valve in the f and e tank is just like a toilet on.....water level drops...ball drops...water is alowed it...water rises and closes it of.

 

[cardob00]

Problem solved...it was the F & E tank...bone dry...was difficult to get too (as boarded up high in loft so couldn't see into it). I stuck a wooden stick in it and it was dry. Filled it with bottles of water (wine bottle narrow neck a good idea to prevent water spilling!) - 30 bottles later was half full according to the wooden stick.

Ball cock arm is in down position I think so should be open for water inlet I presume - think that the water outlet in arm may be completely scaled but can't get to visually inspect it...

So for now, it's filled but presume it will evaporate at some point...

No bleeding required every few hours now and the top loft rad is now nice and toasty too..obv it didn't have enough water to fill it in the system (it was above the F & E tank yes).

Rads seems hotter now too...clean water I guess...

Thanks and what a great forum this is!