List some common causes of an evaporator operating with a low ...

[sheilaspns]

List some common causes of an evaporator operating with a low superheat and a high suction pressure.
 
  What will be an ideal response?

Question 2

Why are electro mechanical control systems often referred to as relay control systems?
 
  What will be an ideal response?

[DylanD1323]

Answer to Question 1

Some common causes of an evaporator with a low superheat and a high suction pressure are:
oversized valve TXV seat is leaking

low superheat adjustment
sensing bulb making poor thermal contact wrong thermostatic charge
incorrectly located external equalizer

Answer to Question 2

Electromechanical control systems are two position controls that use mechanical switches and magnetically operated devices. Units respond to the presence or absence of 24 volt control power. Relays are common electromechanical controls. When the relay coil receives 24 volts, its contacts close to operate a motor or other controls.

[sheilaspns]

Excellent

[covalentbond]

Thanks for the timely response, appreciate it