Explain a method used on walk-in coolers and freezers to help ...

[ec501234]

Explain a method used on walk-in coolers and freezers to help prevent warm air from entering the case when the door is opened.
 
  What will be an ideal response?

Question 2

What is the control voltage used by most residential HVACR equipment?
 
  What will be an ideal response?

[frankwu0507]

Answer to Question 1

To prevent some of this warm air from entering the case, some systems will have a door switch that will shut off the fans when the door is opened.

Answer to Question 2

Most HVACR equipment uses 24 V as the control voltage. This is because, first, under most state and local guidelines an electrician's license is not required to install and service these low voltage wires. Second, most codes do not require that these connections be made at electrical junction boxes. And third, under OSHA regulations, circuits that have less than 80 V fall under less stringent safety requirements.

[ec501234]

Excellent

[Dinolord]

Gracias!