Heatstore - leaking coil???

[rocketman]

Been to a customers house to fault find but didn't have a lot of time.

Problem is over over flow from exansion cistern.

Brief history. 3 seperate visits from heating company, (customer wasn't too forthcoming who though??) in December for 2 different faults. First time it lasted one hour after repair... lady not too sure what problems were, possibly boiler not igniting... possibly not related to current problem.

Back to overflow problem. Husband assures me it's not the float valve. Cistern full of water at about 30ish degrees. When you run the hot water and turn tap off you get a strange sound from the heat store... almost like a cistern valve closing??? Also they have noticed the sound intermitently at night when not hot water has been run. Did fill a pint glass full of hot water but didn't notice it being discoloured. Customer not sure how long it's been going on, they only noticed it over the weekend but not been in the back since before Christmas.

Done almost no work on heatstores before and avoided the houses on this estate since they were built......absolute nightmare too much settlement, leaks, poor water flow problems, numerous boiler problems, pretty damn gash jobs the lot of them. Seen mixed fittings in some of them, Tectite (mixed Textites, classic and pro) and speed fit. All within sight of each other.

Close friends of ours had one of the houses and sold up because of too many problems. I know of two couples who have just given up and started again with new boiler and heatstore and all re-piped.

Anyway, I digress, attached a couple of piccies, was really pushed for time so couldn't get many. Did notice all the insulation at the back is cracked and coming off... I did check but didn't notice the cylinder misshaped so probably damage done during insulation. In the area most of the day tomorrow, might tie valve up in the morning and drain cistern and go back PM to see what happens. Any thoughts or suggestions to prove my theory???

RM

 

[darrenbea]

the open vent on the primay flow should be going stright to the f&e cistren not in to an expansion vessal. theirs a good chance the cylinder is going to ruptures, the purpose of the open vent is to maintain atmospheric conditions in the pipework. it permits any air entering the system to escape and, should the water in the system become over heated, it allows it to expand up the vent pipe and dicharge into the f&e cistern.

 

[stevetheplumber]

doesnt look like any heatstore ive seen in fact im not sure what it is ?
is there a mixing valve on it ? realy need some better pictures and more detail which boiler are there two pumps etc

 

[crafty]

has the coil in the cylinder gone?

unusual problem i know, but the expansion would flow (depending on height of cwsc and ex tank) if this was the case.

any sign of fernos in the drinking water?

 

[REDSAW]

its not shipley park is it?.

 

[Billy Bob Bob]

what the hell is that?????never seen a heat store like that before looks like a normal cylinder

 

[Blackcatgas]

The pipe going in to the cylinder is straight off the mains, thats why its got a pressure vessel on it, this then runs through a coil in the cylinder absorbing the heat from the hot water stored in the cylinder, turn off the supply to that top en try thing and Il bet the tank doesnt overflow anymore, the coil is fubared. it almost looks like a home made heats store made from a normal cylinder, ingenious!.

 

[Jimbob]

ha bet that works well...

 

[Billy Bob Bob]

The pipe going in to the cylinder is straight off the mains, thats why its got a pressure vessel on it, this then runs through a coil in the cylinder absorbing the heat from the hot water stored in the cylinder, turn off the supply to that top en try thing and Il bet the tank doesnt overflow anymore, the coil is fubared. it almost looks like a home made heats store made from a normal cylinder, ingenious!.

yes but if some body had used a normal cyilder it could one day explode

 

[Blackcatgas]

yes but if some body had used a normal cyilder it could one day explode

Why? its only the coil thats presurised, the water in the cylinder is fed from a tank I assume.

 

[Billy Bob Bob]

right should start reading these posts properly then

 

[Renewable M]

Its a normal heat store. Higher pressure hot water performance with the safety of an open vented cylinder.

Main cold in to the bottom, (non return and 3 bar limit restriction) then when you turn on the cold tap, the water whizzez up through the very long (usually finned) copper coil. Guess what...... it comes out piping hot.

The exp vessel is there to take up the expansion as the cold water standing in the coil heats up.

These are mega popular on the continent, often with heating tappings too.

Great for eliminating boiler cycling. No safety discharge, no legionella risk blah blah.

Bloody brilliant. And what's more.... foolproof.

Sounds like your coil is pinholed, which is very bad luck. Usually down to not having a pressure reducing valve on the way in or the expansion vessel knacked.