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Joined: Jun 2003
Posts: 1,143
D
DougW Offline OP
Member
"thank goodness you're here!"

I'm starting an install of a new 100A service for a detached garage for the parsonage of our church.

With my 19 mo. old daughter in tow, I stopped by the AHJ w/ the permit app. Needless to say, bringing "the boss" with on my shoulders amused the staff. She's a charmer... good thing she takes after Mom! [Linked Image] Got the permit stamped, and headed to the church. It was about 1230.

Walked into the school side of the building, fully intending to make a copy of the permit, slap it on the window, and let 'em know I'd start next week.

The door entry system was offline. Finally, one of the staff lets me in. Just as I enter, I notice the familiar smell of burnt insulation, and hear the aforementioned famous words uttered by several folks.

Turns out, about 20 minutes prior, the lights had started flickering. Luckily, they'd had the sense to start shutting down computer & such. Then 90% of the lights went out, and someone reported "noise and a fire" in the mechanical room. By the time someone with a clue went to the basement, the circulating pump motor had fried. They couldn't find the disconnects in the dark, so the Pastor turned off "some of them". [Linked Image]

An elderly member of the church, supposedly a retired spark, "declined" to shut anything off, fearing making the situation worse.

Then Doug arrives on location, with his faithful foreman, Iszabelle.

Supposedly, someone talked to "the power guy", who claimed "he'd be back later to climb the pole", but that "they'd need to dig out front of the building in a box".

Odd, given the fact that the service for the Church comes in under the alley on the other side of the wing. <<BS alert>> Of course, nobody remembers who they talked to to get this kernel of info.

While one of the teachers occupies Iszy (Rule 1 - find something for the foreman to occupy his/her self with so you can get work done) Grab tool belt & flashlight, head downstairs. Find switchbox labeled "furnace pump".

As I throw the switch, I realize I'm hearing a humming noise, which stops when I drop the lever. It resumes when I move it back (very briefly). Odd, given the "no power" nature of the situation.

Throw the main for the building. No significant change of situation. Open switch panel. Grab wiggy - Bus #1 - D E D dead. Bus #2 240 VAC, Bus #3 D E D.

Heard of "dropping a phase" before, but never been around when two have gone.

While I'm down there, I open the cover plate and D/C the motor leads, and discover it's a 3-phase 3/4 horse. Cover the line wires (even though the D/C switch is off), copy the motor info off the plate, and head upstairs.

Get upstairs, tell the Pastor and staff what's going on. They ask me to call the HVAC folks. I contact them, and get severe attitude from the phone chick (slam intentional) about "do they really want us to come out there tomorrow - it'll be time and a half". Then, while I'm confirming with the Pastor, she hangs up on me.

Thinking back, I realize that a B&G circ motor is a B&G circ motor - this one's just a lot bigger than the ones I helped dad replace on out old heating system as a kid.

Took "old smoky" off the pump. Took the time to explain the concept of multiphase power to the assembled staff - one of which kept asking if we could return the motor if it turned out that wasn't the problem.

Displayed scorch marks and molten insultion. Approval was finally given to obtain replacement.

Called Grainger to get a replacement motor. Found out they had an interchange, and they could messenger one up from their distro center for $15. Not bad, given the fact that the motor itself was $865.00!!!
[Linked Image]

(I'm not real familiar with 3-phase, but it seems that, just like government or fire department, it's another excuse to add a zero to the end of the price - YOWCH!)

Ordered the motor.

Waited around for a few hours - motor got there by 1615.

By 1625, had determined that "interchange" and "exact replacement" are not synonymous terms.

The shaft was 1/16th large in D and 1 1/4" longer. It was also keyed instead of indented, and the motor itself had 4" pattern holes in it, instead of relying on a separate frame - resulting in a gap of appx 3/4" even with extreme minimum clearance in the shaft housing.

Had the wife (who had arrived at the church - her workplace) start calling plumbing and HVAC supply houses to find a replacement.

Bad news - the B&G motor had been discontinued by most local suppliers.

Good news - there are two suppliers that had replacements in stock in the Chicago metro area.

Bad news P. 2 - they were either 50 miles away (Alsip), or 75 miles away (Elgin).

Made arrangement to return motor to Grainger.

The wife went down to Alsip this a.m. and obtained new exact replacement motor & frame.

When I get off from the FD tomorrow @ 0700, I get to go play before church starts!

Luckily, the Pastor said I could submit a bill for my time - especially since they know I gve them a (significant) break on hourly, and even at listed rate, I'm cheaper than their HVAC folks!

I'll let you know how it goes tomorrow.

Joined: May 2004
Posts: 697
D
Member
Thanks, Doug, I needed that. I thought I was having a complex day, but it was pretty dull by comparison.

Dave

Joined: Dec 2003
Posts: 524
Member
... What a nightmare!!! Please fill us in on your progress!! Certainly you'll be earning a few well deserved stars in St. Peters book for the effort!! [Linked Image] [Linked Image] [Linked Image]
Russ


.."if it ain't fixed,don't break it...call a Licensed Electrician"
Joined: Jun 2003
Posts: 1,143
D
DougW Offline OP
Member
Got the replacement motor (c/o the wife's road trip) on Sat, installed it Sun. before service. Works like a charm.

After all was said and done, somebody mentioned that the sanctuary has a forced-air furnace that might need to be checked. All power on, motor not running. See post forthcoming about troubleshooting 3 phase motors...


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