×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

THERMOSTAT IN VAV/CAV SYSTEM

THERMOSTAT IN VAV/CAV SYSTEM

THERMOSTAT IN VAV/CAV SYSTEM

(OP)

Hi,

I just want your thought about an issue we are facing now in our design drawing. we are now in the execution stage that's why this issue is raised.

Issue is: 1. we have VAV boxes without thermostat in the drawings. I insisted to contractor that each VAV box should have its own thermostat to control it.am i right?
2. we have multiple VAV boxes( 3 units) in 1 Room, our design drawing states only 1 thermostat. However, I insisted to have thermostat in each one of the VAV boxes.is it
right?
3. we have also CAV boxes in the return ducts which do not have thermostat. I assume that there should also be thermostat even in return ducts.is it right?

I would appreciate your replies.thanks.

RE: THERMOSTAT IN VAV/CAV SYSTEM

Thermostats are not required for every VAV unit is they all serve the same thermal zone. You should talk to the original Engineer who designed this system rather than guessing.

RE: THERMOSTAT IN VAV/CAV SYSTEM

Do what Willard3 said. Then, while you're talking to the original Engineer, ask him to explain the purpose of the CAV boxes in the return ducts.

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

RE: THERMOSTAT IN VAV/CAV SYSTEM

dux77,

I am just now seeing your post. Did you get it resolved? I agree with Willard3 that you only need 1 thermostat per thermal zone, especially if it's an enclosed room. If you had multiple thermostats, they would be set at the same temperature anyway in an enclosed room.

What happened with the CAV boxes on the return? I have never seen such a thing other than on a laboratory or some other critical space where the supply and return must be closely and constantly maintained. It doesn't make sense in my mind to have variable supply and constant return.

please let us know what happened.

RE: THERMOSTAT IN VAV/CAV SYSTEM

How do you have constant return air volume if the supply air volume varies???

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources