worcester highflow 400

[andysang]

Has anyone had a leaking "heat bank"(water storage tank at the bottom of the worcester highflow 400 floor standing combi boiler)
and is it possible to replace the tank???
any advice if you have replaced one would be most welcome

 

[petit_pablo]

Yes it happens and yes it can be replaced.

Whether the costs involved will make it worthwhile is another matter. Its a pig of a job.

 

[andysang]

thanks for reply when you say "a pig of a job" whats involved?can you replace the tank without having to remove the expansion tank/burners/pumps etc?? thanks

 

[petit_pablo]

Not really no. Pretty much the entire boiler has to be disassembled.

 

[45yearsagasman]

Nice job especially if they are really built in from top and sides.NOT

 

[andysang]

doesnt fill me full of confidence .these replys!!!!!

 

[Agile]

I had to let the scrap take an old one I took out as I did not imagine anyone would ever want to repair such an old boiler as that.

The concept is quite good but they have been pretty unreliable.

They are expensive if you must have a replacement fitted in the same place but the latest seem fairly reliable. Its a pretty simple boiler though.

The weather comp unit is very good though and unlike most Vaillant and Viessmann DOES take into account internal room temperatures and you can set the proportionality of each.

Now where is my jacket?

Tony

 

[andysang]

well no definitive answers yet looks like it could be a replacment boiler??
some one MUST have replaced it at some point surely????

 

[petit_pablo]

well no definitive answers yet looks like it could be a replacment boiler??
some one MUST have replaced it at some point surely????

Ive done them hence my answer that its a pig of a job.

 

[andysang]

did you do it sucessfully then?

 

[petit_pablo]

Yes after alot of swearing.

Joy of working for BG, we cant avoid jobs like these. Customer usually prefers we fix the old dogs rather than replace at their cost.

 

[nickso]

has to be in the top five worst jobs on a boiler. most of the top section comes off easy enough but i wouldn't even entertain it without replacing the plastic mainfolds and the isolation valves as a matter of course.

this thread is giving me the fear, i'm off to shiver in a dark corner and hope tomorrow i don't get a hiflow in a garage with a mysterios puddle low down.

 

[andysang]

well it doesnt seem to get any eaiser!! where are the plastic manifolds??and iso valves
thanks

 

[boilerdoktor]

i'm a bit confused by the answers on this post. it's not a horrendous job at all! You don't need to take all the boiler to bits at all. nor touch the plastic manifolds. the tank once disconnected slides out towards you!

the gas valve, pump dont really need to be taken out only the div valve which is held by 4 or 5 screws. the two pipes that come from the bottom manifold can be a bit awkward to get out and back in. a few screws at the sides of the tank and its out! No more than an hour to remove and about an hour or so to fit the new one!

If you engineers are taking the manifolds out etc your doing something very wrong! the trouble is of course the more you remove the more chance of leaks I've done about 8 over the years and i'd rather change the tank rather than the w/w heat exch.

To the op think carefully about doing it! very expensive part (about £700 i think) and if it is the old highflow i wouldn't bother because if your tank is split there may be other trouble ahead (blocked plate common fault on these) If it is the newer electronic maybe it would be worth it! Why has the tank split what is your water like etc. The total job may cost £1000 which is a good way towards a new boiler!

 

[nickso]

you have done 8 and never had anything leak on them afterwards?

nothing on a hiflow, apart from access issues if you have to do everything from the front, is particularly difficult but i have rarely had one that has gone back together without something else leaking.
as a general rule and really not needing the hassle of taking it apart again, if it hasn't had the manifolds done recently i'll just change them, saved me a lot of hassle over the years.

if i get the proper time and it's not a stinking house i quite enjoy doing the DHW H/E.