central heating

[aidsy]

hi all maybe some of the plumbers can give me some advice .

i have oil fired central heating, i had to go into the roof space yestarday for the first time in a long time i noticed the small black plastic water tank was warm , the heating was on, i dont think it should be warm i didnt have time to investage any further , i did check the water circulating pump it was set at position 3 i have turned it down to 2 but will check later today . any ideas guys?

thanks

 

[Burnerman]

So long as your rads continue to get hot, keep the pump on the lowest setting possible. More than likely this will sort your warm tank issue, but do monitor it.
John

 

[aidsy]

thanks burnerman

i have tried the pump setting on the lowest setting "1" and it still heats all the rads fine but when i got into the roof space guess what the tank was still hot there was a 22mm pipe dropping down into the tank when i lifted it out water was running out of it constantly its not going down the overflow so must be going somewhere else , i then set the pump to "3" to check the flow of water in this pipe its now greater, so its back to setting 1 now,, any ideas its a 4bed det house so plenty of rads i dont use 2 rooms so i have turned the rads off at the valves.


thanks

 

[aidsy]

any ideas guys ?

thanks in advance

 

[SuperMario80]

Could be a blockage/(frozen pipe with this weather) somewhere. The water is taking the easiest route which is up the vent.

 

[D_Hailsham]

there was a 22mm pipe dropping down into the tank when i lifted it out water was running out of it constantly its not going down the overflow so must be going somewhere else

It's going back down the feed (pipe coming out of the tank about an inch above the base. This means the feed pipe is not blocked. There may be a blockage between the feed and vent pipe (the 22mm one) where the connect to the main circuit. This is usually just before the pump as in this pic. The vent pipe should hang over the tank, not be immersed in it.

Untitled

• D_Hailsham
• 2 Mar 2009
• 2

 

[aidsy]

hi all problem is still ere pump is now set at level 1 all rads do heat up but take a while and the exp tank in the roof space is still getting hot , if there is a blockage is this something i can do myself (i am an engineer) so good with my hands .
many thanks


aidsy

 

[tamz]

Firstly your system is piped wrong or it would never do this. It should be piped as D_hailsham 's pic

So what is causing it?

My guess for what it is worth, is you have an old system with a low head between the pump and FE tank, there is a buildup of sludge and the restriction of pressure across the system is causing the water to be pumped over the expansion into the FE tank and circulating back through the feed.

It might have only recently or maybe always done this way ( exp pipe dipped into water makes me think it has always been this way) but by this happening it is making your system even worse as it is inducing oxygen to the system water and speeding up the corrosion problem.

Put a system cleanser in (X800) or get a powerflush done to get rid of the crap but sort out the underlying pipework problem too.

 

[Agile]

It may well just be dirt in the system.

Try the X800 for 2-4 hours and see if that cures the problem.

Its does not dissolve anything, only loosen the dirt to enable it to be flushed out.

If its hardened dirt that is likely to be between the feed pipe and the expansion pipe connections on to the system. You may end up having to cut open the pipe here and mechanically clean it if the X800 does not solve the problem.

Tony

 

[aidsy]

got x800 today will try it later and keep u all updated .