Yesterday I was working at my profession putting a "compressor" in a heat pump. One of the things we do to assure safety is remove all of the refrigerant from the system through reclaiming. When the repairs are complete we evacuate the air and recharge the gas.This was a 410A system so the pressures are much higher with this gas. I did the cursory check to see if there was a charge in the system and depressed the shreider valves. I used a tool to depress them and no pressure was there so I determined that the system had leaked all the gas out and would need further repairs.
 
 This heat pump is located in an office along a wall with desks, and secretaries in the office. After a warning that I would be "making a little smoke" I lit the torch and heated a brazed joint up to 1200F to loosen the fitting in order to change the compressor.At this point the entire top blew off the compressor spewing oil all over the ceiling and spraying it all over the secretaries sweater and papers. My helper had his shirt sleeve dowsed with high pressure gas and oil. The secretary immediately left the room. The sound was like a small explosion in there and then a loud gushing sound. The gas from the explosion looked like thick fog...luckily noone was hurt.....I did my best to determine what had just happened. Apparently the shreider tool had failed to depress the valve core and the system was under full pressure when I went to unbraze it.
 
 Long story short...I felt really bad. This was one of those things that even though I had taken precautions  things went wrong. The cores are of a different type than is typical so the tool didn't depress the shreiders.
 
  After a custodial crew was called in  to clean up the mess and the secretary got her sweater cleaned all is well or at least kind of normal . I apologized but that didn't seem to make me feel any better.The part is in and working but man I hate days like that. I WILL double check that valve next time.
 
  Days like that make me want to take a long vacation or maybe not even come back at all.
 
 

Man.....live and learn I reckon. Glad nobody got hurt.

I know what you mean about "some days".
If I didn't know better I'd think the thing blew in here LOL.

She had the right idea.......see ya!

Glad no one was hurt, Starise. It's really good to see that you took responsibility and apologized for the situation.....which is seriously lacking in todays society.
When the going gets tough, Starise will blow it up!!

Glad you survived. It must have made for quite a scare.



BTW, it's a Schrader valve, named after Mr. Schrader.

Don't ask me how I know. :-)

I'm surprised you don't just remove, or unscrew, the core completely rather than just depress the plunger.



Have you taken the secretary some flowers?


best regards,
mike

Yep, the above mentioned already!

No matter the profession, there are always things like that happening... 

Electrical stuff: Did you check to see  if it's off?..... yeah it's off, go ahead and cut the wire......BANG.. it's off now cut it again.... BANG.....  ( I have the burned pliers form this one)  

Fire alarm: got the system on test?.... yeah it's on test... smoke the detector heads.... fire dept show up 5 minutes later really ticked asking who's in charge here?  (phone call didn't get made by maint super)

Sprinkler guys: Ready to flow water into the system? ......Yeah.....  3 minutes later..... it should have stopped flowing by now..... screams from inside the building.... SHUT IT OFF..... ooops, someone busted one of the heads and the new walls and carpet are soaked......(I didn't own that one,,, but I did see it happen) 

always makes for a fun and interesting day. 

We were shooting a commercial spot in a plastics injection molding facility a few months back.

We had noticed some guys outside working on the fire protection system pipes etc.

We had driven our van within the ware house to get easy access to the production floor. We had permission but we were warned to drive carefully. Just as we parked the van a 8" water main up in the ceiling burst open and flooded the ware house floor. We were like... "it wasn't us".

:-)

I love those sorts of coincidences...... just as I flip the switch to turn my system on..... something else happens like the computer system network crashes....and everyone looks at me..... 

"I swear, it wasn't me... I haven't been near that thing" 

 Yes Mike the shrader valve is what I intended to type. I use them every day and only spell it very occasionally lol. These shrader valves are different. A typical core tool won't remove one. I believe they are associated only with R410A . Although I have been certified for R410a for over 10 years these valves are something different. I did figure it out though :P.

  I was back there today repairing two more and everything went off without a hitch. The secretary was even  nice and talkative, probably the most excitement they get there as it's a library office. After it happened the Library director even let me look at  a  book in special collections worth over a million dollars. One of the original copies of Shakespear dated 1623 and a book on electricity signed by Benjamin Franklin, apparently one of his books. Our systems handle this space controlling humidity and such.

 All things considered it went well and I'm glad to be out of there for now.

 Guitarhacker I know what you mean. I have seen a few situations that were sometimes comical and sometimes potentially dangerous. Like the guy who was using a digging iron and hit an electricv main. The explosion blew the iron out of his hands and about 30 ft up in the air. He was completely ok. On another occassion I was present when a backhoe happened to dig through a gas main, that's always a fun thing to watch.

 One of the funnier things that happened was when the electrician hooked up the doorbell wire to the thermostat and the thermostat wire to the doorbell. Whenever you rang the bell the heat came on and when the thermostat called for heat the doorbell rang. Then the time the plumber in a development hooked up the hot water to the toilet. Man talk about cooked cheeks. There was steam coming off the "loo"

 I could tell lots of those stories. One time I was on a ladder up the back of a building and my coworker happened to be standing there looking. I reached up to hold a raingutter to steady myself while drilling. Little did I know that the raingutter had backed up and we are talking a very large rain gutter maybe 50ft long. When I grabbed it about 10 gallons of water came directly onto my head.....he laughed so hard I thought he was going to keel over. I was very wet.

 Oh well enough of this.

Starise, good thing no one hurt.  Before I retired, one of my main jobs was as a "failure analyst" (mechanical engineer) at a large power plant.  I had to determine what happened, why it happened, determine how to make it not happen again, and implement that solution.

Talk about being the fall guy!!!  Management looked to us for the answers, and the lower grade workers just blamed us for everything that happened.  LOL

So is there no pressure gage you could have used or connected to verify the pressure?   LOL