RCinFLA
Solar Wizard
- Joined
- Jun 21, 2020
- Messages
- 3,801
Sounds like you either have a bad start capacitor in the Easystart or the SCR/relay/fuse in Easystart that makes the start capacitor connection to compressor start winding connection during spin up time is bad.
I have had the big black start capacitor in Easystart go bad.
A Trane 3.5 ton compressor should have about a 120-150 uF start capacitor in the Easystart. 270-324 uF is too large mfd. for a 3.5 ton Trane. Because of the voltage ramping it is unlikely to hurt anything, but you will spin up quicker resulting in less peak surge current reduction.
My 368 BT was ordered for the 4-5 ton sized unit and came with 189-227 uF start cap installed. I changed it to 140 uF to lengthen the startup time to about 0.5 seconds
I looked up what Copeland recommended for that compressor model number hardstart kit start capacitor value. They listed 88-108 uF. Hardstart kits do not have the softstart voltage ramp so they can cause a rather abrupt spin up time that is mechanically stressful on compressor if start capacitor value is too large.
This was Easystart recommended start capacitor sizing: You should go by the compressor BTU rating, not the air conditioner unit BTU rating. A high efficiency, large condenser A/C will have a larger unit BTU rating than its compressor BTU rating. My 4 ton Trane has a 38k btu rated compressor installed.
Capacitor Sizing:
72-86MFD - Up to 12K BTU
88-106MFD - 13-23K BTU
108-130MFD - 24-36K BTU
189-227MFD - 37-48K BTU
270-324MFD - 49-72K BTU
115VAC applications can use 250V or 330V rated start capacitors.
230VAC applications must use 330V rated start capacitors.
I have had the big black start capacitor in Easystart go bad.
A Trane 3.5 ton compressor should have about a 120-150 uF start capacitor in the Easystart. 270-324 uF is too large mfd. for a 3.5 ton Trane. Because of the voltage ramping it is unlikely to hurt anything, but you will spin up quicker resulting in less peak surge current reduction.
My 368 BT was ordered for the 4-5 ton sized unit and came with 189-227 uF start cap installed. I changed it to 140 uF to lengthen the startup time to about 0.5 seconds
I looked up what Copeland recommended for that compressor model number hardstart kit start capacitor value. They listed 88-108 uF. Hardstart kits do not have the softstart voltage ramp so they can cause a rather abrupt spin up time that is mechanically stressful on compressor if start capacitor value is too large.
This was Easystart recommended start capacitor sizing: You should go by the compressor BTU rating, not the air conditioner unit BTU rating. A high efficiency, large condenser A/C will have a larger unit BTU rating than its compressor BTU rating. My 4 ton Trane has a 38k btu rated compressor installed.
Capacitor Sizing:
72-86MFD - Up to 12K BTU
88-106MFD - 13-23K BTU
108-130MFD - 24-36K BTU
189-227MFD - 37-48K BTU
270-324MFD - 49-72K BTU
115VAC applications can use 250V or 330V rated start capacitors.
230VAC applications must use 330V rated start capacitors.
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