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spraying contact cleaner while it's Live

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G

g-and-h_electric

Senior Member
Location
northern illinois
Occupation
supervising electrician
Hey guys..... I know this is a little off topic, but the flammable propellants in aerosol cans brought a new hazard to mind. The "new" environmentally friendly refrigerant used in refrigerators and freezers is either propane or butane based (I forget which). How is this safe at all????

I do refrigeration work for the shop that employs me, and saw the labels.

Just an FYI, nothing more from me..... too hot in Chicago to complain!


Howard
 
G

garbo

Senior Member
Joethemechanic said:
I really only use that kind of stuff to clean out gunk and dirt that is binding the mechanical operation. of contacts
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Contact cleaner from the early 1980's had freon as the propellent and mechanics in our shop used it as a degreaser. First the only sold it to electricians then they made them replace the Freon with guess cheap compressed air.
 
Joethemechanic

Joethemechanic

Senior Member
Location
Hazleton Pa
Occupation
Electro-Mechanical Technician. Industrial machinery
garbo said:
Contact cleaner from the early 1980's had freon as the propellent and mechanics in our shop used it as a degreaser. First the only sold it to electricians then they made them replace the Freon with guess cheap compressed air.
Click to expand...
At least they didn't replace it with propane, like they did in hairspray
 
hbiss

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
g-and-h_electric said:
The "new" environmentally friendly refrigerant used in refrigerators and freezers is either propane or butane based (I forget which). How is this safe at all????
Click to expand...

Non-odorized propane. It's safe for the environment (you can just vent it instead of recovering it) but you better drag it outside before you do. Fortunately, the refrigerators that use it use very little compared to one that uses Freon so there isn't much danger. So far, refrigeration equipment that uses propane is limited to the commercial market but in Europe they have used it in everything for many years with no issues.

-Hal
 
mtnelect

mtnelect

HVAC & Electrical Contractor
Location
Southern California
Occupation
Contractor, C10 & C20 - Semi Retired
Refrigerants rated by ASHRAE
1) R-22 is heavier than air and displaces oxygen. That is a problem if there is a leak, and the compressor is in a basement.
2) R-22, R-134A & R-410A are rated "A" (non-toxic).
3) R-454B is replacing R-410A and is rated "2L".
4) While HFCs are rated as a 1 other very flammable refrigerant(s) like Propane (R-290) are rated at a 3. The thought of working with a flammable refrigerant deters a lot of technicians and contractors from using these newer HFO refrigerants.
 
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LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
"Pow-R-Wash PR is a plastics safe contact cleaner that removes oxides and other soils on de-energized equipment."

"Flammable — Do Not use near sources of ignition or energized equipment."

"Odor Mild Ethereal" - It smells slightly unworldly? :unsure:
 
H

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
LarryFine said:
"Pow-R-Wash PR is a plastics safe contact cleaner that removes oxides and other soils on de-energized equipment."

"Flammable — Do Not use near sources of ignition or energized equipment."

"Odor Mild Ethereal" - It smells slightly unworldly? :unsure:
Click to expand...
🤔

Now you got me wondering…

I’ll check with the guys and see which one they are using. We have a cleaner that is applied from a sprayer adapter on a long stick and we use it to spray 25kV substation switches. I know pow-r-wash was on their truck at one time, I “snagged” a can and it’s in my shop..

Anyone remember the Bill Elliot commercial for oil filters?? “I snag ‘em from the shop”. 😅
 
W

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
g-and-h_electric said:
The "new" environmentally friendly refrigerant used in refrigerators and freezers is either propane or butane based (I forget which). How is this safe at all????
Click to expand...

I have methane going into my kitchen, controlled by valves that kids can reach.

Propane and isobutane as refrigerants are not as safe (flammability wise) as the HFC and CFC refrigerants. But the risk is manageable.

I'm comfortable with the tiny quantities used in hermetic systems like small fridges. I don't think I'd be comfortable with 5-10 lbs in a split system connected to ductwork.

I think I'd prefer using propane and adding complexity for fire prevention to using chemically more complex refrigerants. CO2 as a refrigerant is pretty nice but comes with a severe complexity cost if you go above its critical point. Also a good propellant except for much higher pressure.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Occupation
EC
hillbilly1 said:
What is the voltage of the float switch?, You also have to take into account if the spray is conductive.
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I was going to mention I was maybe more concerned about whether it is conductive than if it is flammable.

If it ignites it will only burn whatever you sprayed, as long as nothing else easily ignitable is in the vicinity. If it is conductive you have shock or even arcing to other items of different potential to take into consideration.
 
G

garbo

Senior Member
hbiss said:
Non-odorized propane. It's safe for the environment (you can just vent it instead of recovering it) but you better drag it outside before you do. Fortunately, the refrigerators that use it use very little compared to one that uses Freon so there isn't much danger. So far, refrigeration equipment that uses propane is limited to the commercial market but in Europe they have used it in everything for many years with no issues.

-Hal
Click to expand...
The two large research buildings that I worked at had probably over 200 ultra low temperature freezers that used two refrigerant compressors. The second compressor used a blend of refrigerant but also flammable propane. 15 years ago heard they cost over $10,000 each for maybe 16 to 20 cubic feet of storage space. One research scientist told me he had samples over 15 years old in some of these freezers. My wife's aunt had a refrigerator from the 1930's and when she moved back I the 1970's the moving company refused to move it because the refrigerant was extremely poisonous. Think the freezer only held one ice cube tray.
 
H

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
LarryFine said:
"Pow-R-Wash PR is a plastics safe contact cleaner that removes oxides and other soils on de-energized equipment."

"Flammable — Do Not use near sources of ignition or energized equipment."

"Odor Mild Ethereal" - It smells slightly unworldly? :unsure:
Click to expand...
Found it..
 

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ATSman

ATSman

ATSman
Location
San Francisco Bay Area
Occupation
Electrical Engineer/ Electrical Testing & Controls
We have been using the CRC brand spray contact cleaner and lubricant for as long as I can remember and never had a problem on energized equipment. The instructions say not to use on energized circuits. That is 120v, would not try on 480v stuff. ;)
 

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