Follow up to Expansion tank with hot water

[Pablo]

Thanks very much to the three guys who replied to my earlier posting. Much appreciated. I turned the hot water on and watched the tank to see what happened. There was a continuous steady flow of hot water from the vent pipe into the expansion tank. It showed no sign of stopping. Very disconcerting. I have now shut the system down pending a plumber visiting on Wednesday. I had a new pump fitted two months ago. Perhaps they set it too quick. Although the system was flushed and inhibitor put in at this time, I think there is sludge in the system. The water coming out of the vent pipe was a darkish brown. Does anyone know how much it would cost to convert to a sealed system and whether it would be worth it?

[David Hansen]

On 6 Jun 2006 13:07:41 -0700 someone who may be "Pablo" wrote this:-

Can the pump speed be reduced? Normally there is a switch on the pump.

[John Stumbles]

Yes but as I said in my reply to the original post this is only a workaround. The system needs the geometry of the pipework correcting or possibly converting to a sealed system. This is only possible for boilers with an integral overheat cutout. This would probably cost in the region of £200. [Ducks barrage of 'my mate would do it for 50p' posts]

BTW to the original poster ('Pablo'), please follow up your posts by replying to a post in the original thread you started rather than starting a new thread. That way all correspondence on the subject stays grouped together.

[Pablo]

The pump setting has been turned down and water is no longer entering the expansion tank via the venting pipe. The plumber told me that this piping was too small at 15mm diam and it should be 22mm diameter. He recommended having the piping corrected. I'm going to keep an eye on the system with a possible view to having it power flushed in due course. The plumber said he preferred sealed system but felt that it was not necessary to change my system Thanks for all your help one and all.