Summary for acid cleaning of heat exchangers Discussion
Acid cleaning of heat exchangers is discussed in terms of practical on-site treatment rather than a fixed universal acidity target. Bill Chroniger asks what level of acidity to maintain while cleaning clients’ heat exchangers. In the only reply, the answerer suggests assuming the units contain water and, if alkali buildup is the issue, using off-the-shelf muriatic acid, possibly diluted by 50%, which is another name for hydrochloric acid. The answer stresses safe mixing practice: never add water to acid, always add acid to water. For anyone trying to monitor the bath, the advice is to use pH controls and replace or top up the acid when the pH rises to around 6. The response is cautious and informal, offering a general starting point rather than a strict specification.
Q. We clean heat exchangers on site for our clients. What level of acidity should we try to maintain during the treatment process.
Bill Chroniger
HVAC Contractor – Beltsville, Maryland, USA
2004
A. Hi Bill,
Seeing that no one else had replied to your request, I thought I’d have a stab.
I’d assume that your customers’ heat exchangers had just water inside them … in which case, presupposing alkali build-up, I’d use off the shelf muriatic acid
⇦ on
eBay or
Amazon [affil link] (maybe diluted by 50%) which your local lumber yard would have. Commercially this is also called, as you well know, hydrochloric acid…. but never, EVER add water to acid, please always do it the other way around.
If you really want to ‘measure’ the acidity, you’d have to have some pH controls … and then I’d only replace or top up the acid when the levels bottom off to say around 6 pH.
Does this help? I hope so …
Freeman Newton [deceased] (It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2004