improving pipework for feed and vent

[D_Hailsham]

Try reading what I put

I did.

"It goes feed, boiler, vent, pump" implies that is the correct way to pipe the feed and vent.

In any case your original question is superfluous as you can see, by looking at the OP's "current layout" diagram (first post), that they are not piped as in your question but in the standard way for high resistance heat exchangers.

 

[chris5346]

hi,
i haven't cut the connections out yet but i have removed the f and e tank , the tank had a slime, should i be concerned ?
the water in tank looked clear at first but there must have been silt on teh sides of tank because it soon turned black,
the tank was immaculately cleaned 4 months ago and the boiler has only run for 2 days to test the radiator i fitted in the summer.
i drained some water from the filter and that was clean and also water from drain point downstairs is clear, so i don't know what's going on with tank in loft.
here's some photos :

 

[chris5346]

i have seen that leathery slime in tank before after boiler was replaced,
that white/grey fungus type stuff maybe from another tank i have in loft that is also contaminated
,
that is the

old water tank that i have been using to bail the f and e tank water into ,
maybe evaporation has taken place in loft and contaminated it ?

 

[chris5346]

any advice welcome

 

[Razor900]

That looks nasty!

Is the other tank that's contaminated the cold water storage cistern? Bit concerning if it is.

You probably drew debris down into the feed when you drained the system to move the pump. Next time you will know to clean the header tank out first

It's a good idea for you to drain the cold water down clean it out and buy some Fernox Sterox tablets to kill any unwanted nasties in the system. The instructions come with it

 

[chris5346]

hi , no that round tank is the old water tank that got replaced but was too large to get down the loft hatch , i have been using it to store water .
i don't understand how black silt has been getting into f and e tank , last time i cleaned it like new and used dettol.
yes one time i did have some leathery brown slime and i just scooped off some and flushed the rest into the heating system , since then i have been bailing the f and e tank into that round tank,
i'm going to cut the pipes tomorrow all being well,
what i'm now thinking to do is to re -pipe from boiler to pump and put in a 22 feed connection and try to design it so i can use an f and e tank or sealed system without having to do it again if i seal it up,
good point about the water tank maybe i have contaminated that also - thank you i will sterilize it.

 

[DP]

i don't understand how black silt has been getting into f and e tank , last time i cleaned it like new and used dettol.

Storm, several regulars have told you where the problem possibly is.
Your existing pipe run is flow from boiler to pump with two tees in line. First one (tee a) branch is vent to header tank. Next tee within 150mm tee (tee b) branch is the feed/ vent to header tank

If the 150mm section between tee a and b becomes restricted, water will pump over from vent into header, down the feed pipe to the pump. Hence presence of black silt base of header tank ( silt that previously sat in the system)

Do you need more convincing that you might have blockage in several afore mentioned posts?

 

[chris5346]

yes i can see it's black and coming from heating system but i'm surprised water is so clear in the rest of the system , upon reflection i guess it doesn't take much silt to turn water black.
i was hoping to re-use the vent pipe but maybe that's dirty inside and should be replaced ?

 

[chris5346]

hi,

 

[jeff the gasman]

Did you cut that out with an axe?

 

[chris5346]

chuckle, you should see the size of hole in kitchen ceiling if you think that's bad