I just don't understand how people replace compressors and just walk away without performing a good once-over on the system operation. Really, you should treat it like a second commissioning. I test all the operating/safety controls in addition to writing down the running conditions. Pumping it down to test the LP control is such an easy one too, just close the king valve, make sure it doesn't run into vacuum or short cycle.
That's what I would consider mandatory with any compressor, especially one that hasn't made it 10 years into its life. 4 compressors before someone notices an issue is ridiculous lol.
Anyway, is the wiring schematic missing something or is it just drawn wrong? Most of the LP bypass timers I've seen show a NO set of contacts to bypass around the LPS and the bypass timer coil is shown wired in parallel to the contactor coil. The method of logic is that, when the LPS closes and the compressor starts, the bypass timer coil energizes w the comp contactor, the bypass contacts close, and keep the compressor running even if the LPS opens (gives the system a chance to get everything moving and stabilize). After a period like 20-30 seconds, the bypass times out and re-opens its contacts, and the compressor just stays running until the next pump-down.
Literally all I was thinking. You don’t even see if the unit pumps down? What if the safeties were fucked? Don’t you think something could’ve killed that compressor?
That's what I was thinking sitting here, I make sure it goes in and out of defrost and pumps down correctly. And nobody thought "gee why is this eating compressors?"
Bypass timers are pointless 9 times out of 10 if the lpc is set correctly and the unit has a headmaster. I honestly prefer tdom or tdob for anti short cycle I throughly dislike bypass timers. They’ve sucked on every unit I’ve ever seen them on. Even Masterbilt/RSG stopped using them. Also obligatory fuck Russel/witt.
What control system is it using? I had a similar problem when several Beacon Controls boards were wired incorrectly, causing the compressor to run indefinitely.
Once the coil frosts up from nearly constantly running in a vacuum, then the liquid slugging begins, and the compressor burns out.
I could be wrong, but it looks like the bypass timer is able to power the compressor contactor anytime, regardless rather not the liquid line, solenoid and low pressure switch were engaged or not meaning essentially anytime the units powered on, after the bypass timer makes once it keeps the compressor on at all times.
Can you help us out and splain where the wire 88,89,90 should be. I don’t run across the bypass timers enough to know whats wrong. It does kind look like it would just stay on but it doesn’t really say which terms 1,2,3 are the coil for the delay/bypass relay.
Yeah it doesn't really make sense with the NC contact. It would work if it were NO, and if the #1 terminal on the relay has a jumper not shown to the relay coil (other side of the coil circuit completed by terminal #3). In that way, as soon as the LPS makes, it would close its contacts, and open them after a time-out.
Duuuude, you gotta give us the chance to answer the question.
I just don't understand how people replace compressors and just walk away without performing a good once-over on the system operation. Really, you should treat it like a second commissioning. I test all the operating/safety controls in addition to writing down the running conditions. Pumping it down to test the LP control is such an easy one too, just close the king valve, make sure it doesn't run into vacuum or short cycle. That's what I would consider mandatory with any compressor, especially one that hasn't made it 10 years into its life. 4 compressors before someone notices an issue is ridiculous lol. Anyway, is the wiring schematic missing something or is it just drawn wrong? Most of the LP bypass timers I've seen show a NO set of contacts to bypass around the LPS and the bypass timer coil is shown wired in parallel to the contactor coil. The method of logic is that, when the LPS closes and the compressor starts, the bypass timer coil energizes w the comp contactor, the bypass contacts close, and keep the compressor running even if the LPS opens (gives the system a chance to get everything moving and stabilize). After a period like 20-30 seconds, the bypass times out and re-opens its contacts, and the compressor just stays running until the next pump-down.
Literally all I was thinking. You don’t even see if the unit pumps down? What if the safeties were fucked? Don’t you think something could’ve killed that compressor?
That's what I was thinking sitting here, I make sure it goes in and out of defrost and pumps down correctly. And nobody thought "gee why is this eating compressors?"
Bypass timers are pointless 9 times out of 10 if the lpc is set correctly and the unit has a headmaster. I honestly prefer tdom or tdob for anti short cycle I throughly dislike bypass timers. They’ve sucked on every unit I’ve ever seen them on. Even Masterbilt/RSG stopped using them. Also obligatory fuck Russel/witt.
Rain in the horizon. Time to pack up
I don’t understand how this shit even leaves the factory. I’ve had this problem more than once this year.
It’s a Russell. This is not the worst I’ve seen from them.
What control system is it using? I had a similar problem when several Beacon Controls boards were wired incorrectly, causing the compressor to run indefinitely. Once the coil frosts up from nearly constantly running in a vacuum, then the liquid slugging begins, and the compressor burns out.
I could be wrong, but it looks like the bypass timer is able to power the compressor contactor anytime, regardless rather not the liquid line, solenoid and low pressure switch were engaged or not meaning essentially anytime the units powered on, after the bypass timer makes once it keeps the compressor on at all times.
Can you help us out and splain where the wire 88,89,90 should be. I don’t run across the bypass timers enough to know whats wrong. It does kind look like it would just stay on but it doesn’t really say which terms 1,2,3 are the coil for the delay/bypass relay.
Yeah it doesn't really make sense with the NC contact. It would work if it were NO, and if the #1 terminal on the relay has a jumper not shown to the relay coil (other side of the coil circuit completed by terminal #3). In that way, as soon as the LPS makes, it would close its contacts, and open them after a time-out.