hot water cylinder pipe blocked up

[matz]

well, following on from last thread i posted, we now have a nice shiny brand new boiler! but now the hot water cylinder is giving some grief. the central heating system is boiler plus hot water tank with immersion and for the past 5 years we've just had the immersion on 24/7 as when we bought the house there seemed to be a prob with the diverter valve.

Now, with new boiler and what i thought would cure the prob of the diverter valve a new valve, the hot water via boiler still won't work and the guys say the return pipe? from the cylinder is blocked. They say we prob need a new cylinder. the existing cylinder is about 23 yrs old so is it like our 23yr old boiler was? ie hanging on for grim death and do they block up like this?

Just need some pointers if possible before i fork out another load of dosh that i don't have

 

[seco services]

They do block up with age/crud in system and you say you haven't used it for 5 yrs.

 

[matz]

out of interest, what diameter are the pipes inside the hot water cylinder ie the ones that block up?

 

[seco services]

About 28mm

 

[matz]

28mm thats pretty thick pipe - is it not feasible to unblock it? The heating people were talking about weaknesses around the unions on the side of the cylinder though perhaps making it start leaking etc obviously i don't want to mess about with it if it leads to more problems (like contimually welding a rusty car) but neither do i want to shell ou the money for a new one if theres no need, which I'm guessing supplied and fitted is £400-£600?

 

[seco services]

Can you not remove it yourself and have a look ?

 

[matz]

Can you not remove it yourself and have a look ?

no, dont know enough about it nor have the time how do you access the inside piping of a cylinder anyway? fiddling with a 23 yr old copper cylinder seems a recipe for more grief to me unless you know whats what!

 

[seco services]

You need to disconnect the 2 pipes going in horizontal on the side of cylinder.

Thats the coil.

 

[matz]

You need to disconnect the 2 pipes going in horizontal on the side of cylinder.

Thats the coil.

so you disconnect those pipes, you stick a hose in to the pipe going into the cylinder and turn in on (catching the water obviously) and if it flows ok its not blocked?

surely not that simple

 

[seco services]

Useally the crud go's solid
you can stick a drain auger through first see if it's clear.

The blockage could be on the outlet return pipe rather than the coil.

Has the return out the bottom got a red gate valve onit by any chance ?

 

[matz]

gate valve - yes. He's had that off and its working ok. also taken the return pipe out of the cylinder - that pipes ok. Been poking with a coat hanger and clear water trickles out also with some black water. Other than that, tricky for me to say for sure whats going on as he said he'd bunged the top to stop water pouring out. he was adamant the only cause would be a blockage.

any other causes of the water not flowing through? Its a well set up system not a diy bodge........