Acids

LarryC

Hydrofluoric acid !!!!! What kind of concentrations?

When I worked in semiconductor fabrication, we used HF and it is REALLY NASTY STUFF. A HF acid burn, got you front of the line priority at the Emergency Room. That stuff eats thru your skin and muscle, and then collects in your bones.

LarryC

Techman

Acids

Professor!When things go bad,what types of acids are created with the new refrigerants and new oils.?thanks!

Eugene Silberstein 3

Hydrofluoric Acid

Hydrofluoric acid....

Brad White_102

Yeah,

one of the few acids that eats glass... generally used to dip glass for cleaning of imperfections and as you said, Larry, in the silicon chip industry... strong stuff. You are right about bone absorbtion, fluoride will do that to you.

I am as surprised as you that HF is the product of breakdown. Who knew? (Dr. Silberstein of course!)

jim lockard

How does

one test for HF? and what do you nertulize it with? J>lockard

Eugene Silberstein 3

You can use...

You can use any of the acid test kits presently on the market to test for HF. The cleanup procedures would be the same for any other acid situation that was encountered on an R-22 system.

Eugene Silberstein 3

Concentration....

The amount of HF formed in a system depends directly on the amount of moisture in the system. The hydrogen that bonds with the fluorine comes from the water or water vapor, so the more moisture the system contains, the more acid will be formed.

And yes... It's really nasty stuff!

I have a very good friend who was doing a compressor replacement after a compressor motor burnout. Instead of cutting the discharge line to remove the defective pump, he used his torch to free the line. Needless to say there was still pressure in the system and the compressor discharge port became a blowtorch of sorts. Not only did his uniform shirt melt onto his body, he also suffered burns do to the burning oil and acid burns to most of his upper body and face. Definitely nothing to mess with.

jim lockard

professor

Will baking soda neutralize HF acid? Should a spill occur. Thanks J.Lockard

Eugene Silberstein 3

Baking soda

Baking soda definitely does neutralize acid. so I would say yes in the event that, let's say, a compressor containing acidic oil is accidentally dropped on the ground.

I would, however, warn against pumping a baking soda solution through a refrigeration system in an effort to remove any residual acid. (wink wink). For that I would rely on oversized liquid line and suction line driers that sould be replaced a day or two after the repair has been made.

Brad White_102

Neutralizing

If spilled on one's person, plenty of fresh water for long periods of time is critical, followed by immediate medical attention of course. But it is strongly advised not to neutralize in situ on the person due to the eruption reaction (true of any acid spill worthy of treatment) whereby hydrogen is also released. This reinforces not pumping baking soda or other neutralizer into an enclosed system as you point out.

So, Professor, this formation of HF applies to any HCFC, HFC refrigerant when in contact with any water? Or is it a tri-reaction with oil, water and refrigerant? I find this fascinating and had not heard of this before.

Eugene Silberstein 3

It's a combination...

It's a combination of water/water vapor, heat, refrigerant and oil that allows the nasty to form.

You also mentioned HCFC refrigerants, which, in addition to hydrofluoric acid, can lead to the formation of hydrochloric acid, given the chlorine content.

When I teach younger technciains who have a few years under their belts, I find it very important to discuss the acid issue. Many technicians learn the field "in the field" and are never taught about the dangers of acid formation.

Most of the old timers in the business rarely thought twice about taking a big whiff of refrigerant vapor in order to determine if acid was present in the system. That, in their opinion, was the manly thing to do and anything else proved damaging to your manhood. Well, being that I'm kind of additcted to this thing called breathing, I'll stick to the acid test kits and leave the refrigerant whiffing to those who have absolutely nothing to live for.