Plate heat exchanger on my combi..... blocked again?

[beefster]

6 months ago the shower kept going hot and cold and this coincided with the burner on my combi cutting in and out. I was rightly advised on this forum that the P.H. exchanger (PHE) was prob blocked. So i took it out and cleaned it out using some proprietary flushing agent and high pressure hose etc. Its lasted 6 months and is now doing it again despite flushing the whole system and adding the usual inhibitor etc.

Was it a mistake to try and clean the PHE out, should i just have put a new one in?? Can I acid flush clean the PHE or do i just throw it away?
What is the best way to help to stop this happening in future??
Are towel rails in the system a problem..... I noted that the inhibitor manafaturer advises a double dose of inhibitor if towel rails are in place??

Its an absolute pain to get the PHE out of my boiler as there is a conversion kit fitted to allow top feed of all pipework which blocks the removal route...... lovely.... NOT!

 

[Agile]

There is no point in replacing a plate HE if you are able to clean it properly.

The dirt comes from the radiators!

The only way to largely stop it is to put a filter in the return to the boiler either gauze or magnetic.

But there is also a rare condition where the boiler can produce dirt inside itself if it has not been properly set up.

Tony

 

[beefster]

Thanks Tony.

Any info on the filters and where to get them? I am limited on space as the return comes from above the boiler thru the ceiling which is... obviously under the shower up stairs! I might be able to fit one a little further away tho.... off to investigate.

There is no mention of fitting a filter in the installation manual I have?

When i last cleaned the PHE a lot of black scale came out rather than sludge.

 

[kevplumb]

But there is also a rare condition where the boiler can produce dirt inside itself if it has not been properly set up.

bullshit

 

[Slugbabydotcom]

Magnaclean and Fernox boiler buddy are the two most common proprietary filters best suited to your requirements.

 

[beefster]

Ta all.

Anyone got any advice on cleaning the PHE??

Years ago when i was an apprentice on building services..... the plumbing team used to acid flush (i think) the calrifiers. is there something similar to use on a PHE to clean it out????

 

[Agile]

bulls**t

It may be bullshit to you but its Ankerite to me!

 

[clf-gas]

Ca(Fe, Mg, Mn)(CO3)2, Calcium Iron Magnesium Manganese Carbonate

Nice one Tony! :

 

[beefster]

And the symptoms are.........

 

[ollski]

As Tony says there is no need to replace the heat exchangers if you can clean them properly, but personally as there is absolutely no way you can check how well you have cleaned them I always replace them, also saves farting about buying, using, storing and disposing of dangerous chemicals.

 

[Slugbabydotcom]

As it happens I cleaned one out today. I slapped it about a bit then backflushed water through it. Then I filled it with boiling vinegar and left it while I had cuppa. A repeat slap and flush got a load more crud out of it.

I dont know whether this is an 'approved' method or what but I used what I had to hand. I was a long way from home and determined to get something sorted for a now grateful tenant able to get her first proper bath in weeks.

Luckily this was on a Brittony combi SE 80 and was a doddle to get out and in again

I'll recommend to the landlord that a Magnaclean be fitted but I bet he wont part with the money and I'll be back to it next year.

 

[beefster]

Thats virtually what i did last year......... 6 months on its playing up again, and its a total pain to get out!
Might buy another one and get the other one chemicaly cleaned and ready to go in as, if and when needed.

 

[beefster]

Re the magna clean...... had a look and am impressed.
Will one work on an existing system or do i need to clean it all out first....... found one for a bargain £75

 

[2face]

i use the magna clean wen i power flush a system .. help a lot and it looks great wen u show the customer the shi te that comes out .. they are designed to be fitted and left on the system .. great little invention .

http://www.magnaclean.co.uk/feedback.shtml

 

[beefster]

Looks like the best option is a to buy and fit a new plate to plate heat exchanger and a magnaclean.