Trane Package Unit: YSC Re: Ignition Lockout Codes Trane YSC package units are multi-stage gas/electric units. These units utilize an Ignition Control Board (ICB) with a built-in spark generator for electronic ignition control. The ICB has a diagnostic light to indicate heat status. ...

Trane Rooftop Unit: YSC Re: Cooling: High Discharge Pressure / High Head Pressure As the system runs in the cooling mode, the discharge pressure exceeds the normal operating pressure. R410A System High Head Pressure = Above 400 psig Qty Possible Causes (From Most to Least...

Trane RTU: YSC Re: Economizer Wiring / Setup The economizer dampers and control are factor installed, but must be field setup and wired. There are normally (2) plugs that must be attached to the economizer in the field. Power & Communication = (Blk, Blk, Red, Blu) Mixed Air...

Package Unit: YSC Re: Heating - Code 4 Code 4 = High Limit Switch Open ► The YSC rooftop units can have either a Belt-Drive or Variable Speed Blower. Qty Possible Causes: 2 Broken or Loose Blower Belt 1 Bad Blower Motor Bad Ignition Control Board (ICB) ...

Package Unit: YSC Re: Heating - Code 6 Code 6 = Roll-Out Switch Open Qty Possible Causes: Bad Heat Exchanger Bad Limit Switch Blocked Burner Bad Control Board CHECKOUT: 1. Check Limit Circuit