Troubleshooting Commercial York Package Unit

During maintenance I found the unit not operating correctly. I found a fault code on the VFD in the blower compartment. I also found a loose belt.

[@raddo555]

So all this for a loose belt!?

[@HVACServiceTechnicianTalk]

I ended up installing a new belt. The fault code never did come back. Small chance my fault on the VFD was from a power outage. I have seen VFDs throw all sorts of codes when that happens.

[@natenielsen7066]

I have two brand new units exactly the same as this only been running for a month and they both are continuously hitting the same VFD errors. Any help would be appreciated

[@boduke2299]

With cooling mode energized shouldn't the vfd go to 60hz the fan should be ripping.

[@diazinc462]

not if you calibrated and did a proper air balance. ramping up air speeds could cause supply temp issues depending on the duct work

[@mark.r8900]

my york rtu unit is in heat mode and giving a HS1 limit switch error on the smart simplicity control. I've checked the high limit switch and it seems fine. The manual for the control says the LS1 has tripped 3 times within an hour. This results in the HS1 LIMIT SWITCH LOCKOUT. Any help would be greatly appreciated. Thanks.

[@samuelsech2278]

Board might need to be updated...I had same situation on York rtu

[@diazinc462]

fan speed isn't fast enough causing the unit to trip. jump up your fan speed or get a higher rating limit switch. if you have a VFD on heating make sure your fan speed is at 100% on each stage.

[@amfmechanicbowlingcommunit5048]

How Do I test my VFD speed to see if it’s running in full cooling ? for sample, I know that a degraded fan signal ca results in the fan speed being lower that the board is requesting. For example, at fan only 50% fan signal should be 30 HZ on the VFD. At 100% fan signal (full cooling) the VFD should be running 60 hz. If you see something different, the board may need to be replaced. Any Idea?

[@diazinc462]

make sure your board is set to Fixed variable speed . if you set cooling stage 1 fan speed to 100% your vfd should've bumped between 56-60 if its a low number 35-43 change your board.

[@RefrigerationDevil]

@@diazinc462 thanks sinsei