cleaning inside of heath exchanger?

use heating system cleaner, that's what it's for, you can get it at a plumbers merchant.
p.s. you shouldn't be doing this unless you are qualifed person.

Ian
September 2009

John,

I use Caustic Soada at home and whenever I do something dissolves that shouldn't - it's dreadfully corrosive.

If your Heat Exchanger is messed up inside then perhaps a pressure washer or just a regular hose pipe might do the job. These things are prone to rusting and the continual heat cycling will not help - you may, if you're too forceful just accelerate the death of it.

I wish you well with the clean up & sorry but your question did make me choke on my cornflakes...

I found this on another help site...

"The chemical required depends on the type of contamination in the HE.

An old Netaheat or similar in an otherwise clean system usually has calcium and magnesium carbonates and complex carbonates with some iron atoms.

Hydrochloric acid is good on both of these but only suitable if the HE is outside! Otherwise sulphamic acid is best and bought as DS3.

Iron compounds respond well to citric acid, DS40 is mostly citric with some malic acid.

I use a mix of DS3 and citric acid in proportions depending on the amount of iron compounds likely, typically 4:1 initially. Sulphamic acid is not very effective below 80*C.

Kettling is usually caused by lime scales and treated as above. This can happen due to faulty commissioning on combis and most likely on 28 kW units rather than 24 kW when the heating output has not been set to the demand.

Most newer sealed systems are usually only blocked by iron compounds and here citric acid products are suitable. And to keep Keith happy the FX2 is fine. Again best when at about 60*C if the gassing can be controled.

I give all this information for professional use NOT for DIY as full body protection should be used and knowledge of dealing with spills and chemical burns to the skin is essential. And of course eye protection is needed. "

Peccavi
September 2009

Dear Mr Peccavi,
Sir you jumpt the gun,I have not used costic soda,I was only asking wich solution would one use to clean the inside of a heath exchanger,let me tel you its one hell of a mesh in side!
Have you a solution for me please?
JOHN

John de_Ronde
September 2009

This is a joke question isn't it?

Caustic Soda is good at dissolving proteins, grease, paint and some plastics by accident. It burns the skin and can cause blindness if it gets in the eyes - there's nothing of any interest inside your heat exchanger to the chemical action of caustic soda.

Specialist engineers often put rust inhibitor in heating systems - periodic flushing cleans out any sludge.

I suspect you may be the first person ever to use caustic soda - you must report back.

Good luck...

Peccavi
September 2009