26 Vapor Injection Error MP4000

Description 

Vapor Injection Error 

• Occurs during pti, brief pti and function tests. 
• Power consumption does not increase when activating economizer valve. 
• Current consumption not correct for valve position. 

Corrective Action 

• Enter Manual Function Test and start compressor and evaporator fans on high speed, with digital valve off, operate vapor injection valve and observe current consumption change. An increase in current consumption is expected. 
• Check vapor valve function. 
• Evaluate economizer Tx valve operation. 

NOTE: This alarm can be activated in low ambient temperatures where condenser temperature may not be high.