donf
Jul 26, 2016, 05:40 AM
Last night I was working at a school (277/460 environment) troubleshooting an HVAC wall encased unit that had not worked in a year.
The problem was given as no power, however, the primary fuse was good and the one conductor I could get to was hot (277 v). So we decided to pull the unit out and get to all of the conductors that were jammed under the unit.
My partner takes the frame and pulls the unit out, Sparks and smoke all over the place!
Turned out that a year ago the unit was replaced, but never actually connected (the reason it was dead). The fun had just begun. There were several conductors exiting a 3/8 conduit that had been cut off (not reamed or filed, just cut off) All three phase conductors were hot. The weight of the HVAC unit cut the wires on the sharp edge of the conduit.
Apparently the tech who installed the unit, just cut the conduit, capped off the conductors and then slid the new unit into the box. No connections to the unit was made because the conductors were way to short (now they are even shorter) and told the school the unit was in and "here's the bill.".
Now the guy is retired and out of the business. It looks to me as if we now have to bust down through the concrete floor to get at the existing conduit, put a J box in and re-pull new conductors. All because the installing tech didn't just back-away and call for an electrician. GEEZE!!
The problem was given as no power, however, the primary fuse was good and the one conductor I could get to was hot (277 v). So we decided to pull the unit out and get to all of the conductors that were jammed under the unit.
My partner takes the frame and pulls the unit out, Sparks and smoke all over the place!
Turned out that a year ago the unit was replaced, but never actually connected (the reason it was dead). The fun had just begun. There were several conductors exiting a 3/8 conduit that had been cut off (not reamed or filed, just cut off) All three phase conductors were hot. The weight of the HVAC unit cut the wires on the sharp edge of the conduit.
Apparently the tech who installed the unit, just cut the conduit, capped off the conductors and then slid the new unit into the box. No connections to the unit was made because the conductors were way to short (now they are even shorter) and told the school the unit was in and "here's the bill.".
Now the guy is retired and out of the business. It looks to me as if we now have to bust down through the concrete floor to get at the existing conduit, put a J box in and re-pull new conductors. All because the installing tech didn't just back-away and call for an electrician. GEEZE!!