E-27, E28, Err45 – Over heating (type 1, type 2 , type 3 inverters) , Fan is not running

E27, E-28 codes are not same E-27, E28. The position of “-” at Error message is very important. If E27 instead of E-27or E-28 instead of E28 is displayed on the compressor display please click here.

!Perform any service if;
• Person going to work on the compressor is certified,
• Compressor completely shut down and electrically isolated
• All compressed air is discharged inside the compressor
• Compressor is completely isolated from the compressed air system.

*Compressor Element temperature must be no less than 75C and no more than 95C. Under some circumstances temperature of the compressor may exceed the permissible temperatures. That is when compressor is to be considered as over heating.
Compressor fan(s) kick in when compressor element outlet temperature reaches to 185F(85C) and stops at 167F(75C). fan start stop is commuted by either a separate contactor or inverter. The single inverter design incorporates fan control device internally and can not be seen or modified by service techs.

!In order to serve Us Air Compressor customers faster and better tin order to diagnose product related emails(subject or body part) or text message (body part of the picture sending not as a separate message) , compressor serial number must be written in the communication media.

Check below to diagnose the problem.

• Room temperature where compressor is installed is higher than 105F(40C).
• Compressor oil cooler is blocked. Clean oil cooler, inside of the compressor and electric box.

*Dirt accumulated at the cooler is also going to accumulate at fan blades, inside parts like contactors, relays, inverter. Clean all parts with dirt/ust or any other foreign substances. Use dry air and/or sprays or liquids specially designed for electric and electroic components for cleaning. Do not expose dirt/dust while cleaning coming out on to other parts of the compressor.

• Lack of compressor oil. Top it up.

*Do not add oil more than top line of the sight glass for rectangular sight glasses or exceeding the glass top level for circular sight glasses. Excess oil may cause oil carry over to the downstream and blow out oil from the intake valve or air filter

• Oil filter and/or separator filter is blocked, oil is degraded or contaminated. Change oil do the service.
• Ventilation air flow is not enough. Consult to HVAC company to have correct ducting into where compressor is located and have the hot air coming out from the compressor cooler ducted outside the room away from the suction side of the compressor or the inlet duct.
• Check all three phase (if compressor single phase, phase voltages) are correct. Correct if one phase is not present or voltages are within permissible limits.

!Only certified electricians must check the functionality of electrical devices like fans, contactors, transformers, relay boards, control boards and all electrical devices. Us Air Compressor can not explain or guide people who are not certified and already trained to deal with and execute performance checks of electrical devices. Requesting guidance or explanations about functions and controls about electrical device will be refused for the safety of the user and compressor.

Fan is driven by a contactor

• Check control transformer. Change transformer if faulty.
• Check if the cooling fan(s) are in working condition. Change fan(s), if faulty.
• Check if the contactor is working. Change contactor, if faulty.
• Put a jumper in between terminals PrB and Cb located on the inverter control board. Check if fan is working. if fan starts running replace the relay board that has the termnals Prb and Cb located.
• Cooling fan(s) are running in the wrong direction. Change main input phases of the compressor.Changing main input phases will not effect the direction of rotation of main motor. Direction of rotation of the air flow must be out of the top of the compressor..
  
  

Single inverter design

• Check if the cooling fan(s) are in working condition. Change fan(s), if faulty.
• Cooling fan(s) are running in the wrong direction. If fan connected as 3 phase to inverter, swap 2 phases to run the fans in the correct direction. For single phase fans with a capacitor, change capacitor connections to create the correct phantom leg.Direction of rotation of the air flow must be of of the cooler.
  
  

Fan is driven by extra inverter

• Check if the cooling fan(s) are in working condition. Change fan(s), if faulty.
• Check if fan inverter is not faulty. Set parameter F11.00 to 0 and F01.17 to 0 on fan inverter. Push Run button on the fan inverter.
  1. Fan(s) starts running slowly to full speed. Stop the compressor and check wiring is correct in between fan inverter and main inverter is correct and intact. Set F01.14 to 1. Put a jumper in between terminals PrB and Cb located on the inverter control board. Check if fan starts working. if fan starts running replace the relay board that has the terminals Prb and Cb located or ask Us Air Compressor service to assign the third relay on the compressor to be assigned to fan and connect wires to Ta, Tc from Prb, Cb of the relay board.
  2. If fan(s) starts not running change the inverter or check the error displayed on the fan inverter. if no error is displayed change F01.14 to 1 and test the inverter as explained at item 1.
• Cooling fan(s) are running in the wrong direction. Change main input phases of the compressor. Changing main input phases will not effect the direction of rotation of main motor. Compressors equipped with fan inverter, change inverter fan output phase sequence. Direction of rotation of the air flow must be out of the top of the compressor.
  
  

!If compressor element temperature rises 100C, compressor will reduce the max. allowed speed to a lower value, pump almost half of the air so that it can keep working with less cooling demand. Whenever temperature drops below 90C compressor will start runinng at the full speed and deliver the max air flow it is designed to.