CVHE-020 capacitor grenade

[reefermadness]

I have a CVHE grenading the oil pump start capacitor. Chiller has been offline for 4 years with power on to the heater oil is hot and sump is full. quoted new pump and pump motor. am I missing something?

[drivewizard]

My first reply didn't stick so i will try again.
After you change oil pump, I would drop brg insp cover and try to spin shaft with a large socket and BIG cheater bar. Have oil pump running while you do this to get oil circulated in journal bearing.
If this motor sat fro 4 years and wasn't turned over every 6 months or so, the front journal bearing likely has taken a set.

If you can't get shaft to turn using a large cheater bar, then try starting with starter, but leave the refrig out of it. Will save you a step if it trips on O.L. at startup. Cause you be looking at an overhaul then.

[Healey Nut]

Have you tried replacing the capacitor and relay to get the pump to run ??
Thats a whole lot of work and expense to pull the charge to do the pump etc when all you might need is a 20$ relay

[reefermadness]

I changed the capacitor Trane didnt have the relay in stock and they dont give the specs on this current relay. relay was not stuck closed when I checked it. the oil pump has to be tight sitting that long.

[Healey Nut]

the oil pump has to be tight sitting that long.


Why????

I would be changing the relay and capacitor first before you look like an idiot for doing a whole bunch of work that wasnt needed ??????

[reefermadness]

I replaced the capacitor. the relay is not in stock trane has to get it from the factory. the oil pump will run but the relay is holding in too long due to the high amperage of the motor. if the relay holds in too long the capacitor explodes. the relay is not stuck closed. this is a current sensing relay isint it?

[klove]

I responded in the AOP section, also, so here we go again.

That's a start capacitor. If it's blowing up, that means it's in the circuit past start up. You've probably got yourself a bad current sensing relay, or it's wired wrong.

[triggerhappy]

If the motor is drawing lock rotor current and the start winding is not dropping out you need to change the relay or at least pull the wire and see what happens.

[R123]

I replaced the capacitor. the relay is not in stock trane has to get it from the factory. the oil pump will run but the relay is holding in too long due to the high amperage of the motor. if the relay holds in too long the capacitor explodes. the relay is not stuck closed. this is a current sensing relay isint it?

Why don't you just wait for the relay to come in? If you expedite it, they will drop ship it from the factory.

[reefermadness]

I cant find the close and drop out amperage on the relay. any one know what it is?


Thanks,

[Nuclrchiller]

I always change both capacitor and relay together. Cheap insurance for customer. Also, does this chiller have a refrigerant pump? If so, the pump shaft could be seized. I think I remember hearing some were assembled at the factory with excess Locktite 515 and some would find its way to that shaft and seize it up. I do remember on one startup having to open that pump and spinning the shaft manually when it failed to test run. I always did that test prior to evacuation so I would save a whole lot of additional time and effort dealing with the charge. Just remove pump cover to access the nut on the end of the shaft. Of course if the chiller is charged you will need to recover it first.

[Phisher]

Put a hard start capacitor on it.

[Screwit]

I cant find the close and drop out amperage on the relay. any one know what it is?


Thanks,

Not sure on the design your working on without serial numbers but for the liquid refrigerant pump 3/4 hp motor design the relay is rated to pick-up at 24.75 amps and drop out when the motor current drops to 20.45 amps. The original oil pump 1/4 hp motor design relay was 10.8 and 9.0 amps