So I get the call about 5 pm last night.
"The range won't shut off".
See, there is a neat relay/contactor setup that, when one (or all) of three light switches (left/middle/right) is turned on, also turns on the air handler and enables the air compressor that turns the target holders. As it had always worked, no one had ever worried.
Until Saturday evening.....when it stopped working correctly. Turn off the lights and the big fan keeps running. Not what is spozed to happen.
As I am the closest member to the range, I get the call.
My first thought was to simply turn off the breaker and wait for another day.... But the breaker that controls the lights and fan also powers the sewage ejection pump and the heater for that small room where the pump is located. (And last time we had issues with the sewer pump, at least one idiot ignored the signs and used the terlet....with messy results)
So I opened the control box, hoping to see something obvious.
No joy.
And, of course, while it appears that (at one time) there was a diagram of some kind for guidance on the door, it fell off or was removed long ago, leaving only the glue behind to mock those who might need it.....
So I had to close contactors one at a time, and follow the wiring (which was really nicely done, it looked like the interior of an Otis Elevator cabinet) and figure out how the thing worked.
And, while it took an hour and a half, I traced the logic and figured which contactor was stuck.
Pried the welded contact apart, and (for now) everything works).
Kinda proud of that diagnosis. Haven't worked relay logic for over 25 years. But I can still do it. So it is (sorta) fixed....For now.
Simply worn out and pitted contacts. But all the others are worn as well.
Someone is gonna have to replace the contactors ....all 5 of 'em.
And, since there are only 3 of us that have the ability (much less knowledge) it's gonna fall on us. And since one is pretty much crippled, and the other is nearly 80 years old, it's gonna be me.
"The range won't shut off".
See, there is a neat relay/contactor setup that, when one (or all) of three light switches (left/middle/right) is turned on, also turns on the air handler and enables the air compressor that turns the target holders. As it had always worked, no one had ever worried.
Until Saturday evening.....when it stopped working correctly. Turn off the lights and the big fan keeps running. Not what is spozed to happen.
As I am the closest member to the range, I get the call.
My first thought was to simply turn off the breaker and wait for another day.... But the breaker that controls the lights and fan also powers the sewage ejection pump and the heater for that small room where the pump is located. (And last time we had issues with the sewer pump, at least one idiot ignored the signs and used the terlet....with messy results)
So I opened the control box, hoping to see something obvious.
No joy.
And, of course, while it appears that (at one time) there was a diagram of some kind for guidance on the door, it fell off or was removed long ago, leaving only the glue behind to mock those who might need it.....
So I had to close contactors one at a time, and follow the wiring (which was really nicely done, it looked like the interior of an Otis Elevator cabinet) and figure out how the thing worked.
And, while it took an hour and a half, I traced the logic and figured which contactor was stuck.
Pried the welded contact apart, and (for now) everything works).
Kinda proud of that diagnosis. Haven't worked relay logic for over 25 years. But I can still do it. So it is (sorta) fixed....For now.
Simply worn out and pitted contacts. But all the others are worn as well.
Someone is gonna have to replace the contactors ....all 5 of 'em.
And, since there are only 3 of us that have the ability (much less knowledge) it's gonna fall on us. And since one is pretty much crippled, and the other is nearly 80 years old, it's gonna be me.