hot gas bypass

[packageengr]

Hi Experts! Its my first time to post a question here.
Currently, I'm assigned to handle a DX refrigeration unit that is only require to run for 3-5 times a month(30 hrs per run). One requirement that I really do not have enough knowledge is about the hot gas bypass.

-Can anyone explain it to me?

-Does 0% hot gas bypass means that we do not require false load to keep the evaporator running and to prevent it from short cycling or its just because of its application(operates 3-5 times a month)?

Hope to get answers.

Thanks!!

 

[MintJulep]

Good answers start with good questions.

 

[berkshire]

Hot gas is usually required to prevent the evaporator from icing up. If the evaporator is not icing you do not need hot gas.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

 

[davster01]

Good afternoon all,

I have searched the web trying to find a shower exhaust fan with a built-in heater (infrared)in it. I am looking to exhaust approximately 100 CFM at 0.5" W.C. The typical fans I have come across on the web cannot work with such static pressure. To you knowledge is there any product out there that can meet my requirements?

Thank you
Davster01

 

[packageengr]

Thanks for your answers.

Another one, what do you mean by hot gas bypass turndown 0%? does it mean that we dont require it?

Appreciate your quick response.

Regards,

 

[Drazen]

that could be something like "loss of declared heating capacity is zero during hot bypass cycling", for the rest look at the berkshire post.

of course, capacity IS always somewhat lost during bypass, but if manufacturer declares weighted average where time of not having heating is included, and if cycle is as short as possible, they can use such marketing tricks without diverting truth.

 

[cdxx139]

The purpose of hot gas bypass is to keep the compressor running during low loads.

What is the purpose of the 30 hours of cooling? Will it be 100% or modulating? How many compressors and staging? Do you need to modulate cooling? Then you should provide the hot gas bypass. The occupant comfort element coems with an energy hit.

knowledge is power