+ Reply to Thread
Results 1 to 9 of 9

Thread: Pneumatic VAV to DDC Retrofit

  1. #1
    Join Date
    May 2019
    Posts
    4
    Post Likes

    Pneumatic VAV to DDC Retrofit

    Starting a new project in our office. We're doing a demo and as part of it, I'm planning to convert some old-ish VAV boxes with KMC CSC-2003 pneumatic controllers to wireless DDC controllers. Seems simple right?

    I am planning to:
    -pull off the KMC controller and pop the new controller actuator onto the shaft of the existing damper.
    - I think I can reuse the pressure ports and hook the tubes to the pressure inlet of the new controller. Not exactly sure what type of flow measurement is in the existing box.
    - Run 24V power to the new controller
    - Not going to be using the hot water coils (VRF retrofit) so the hot water valve will just be abandoned in place.
    - I might add a SA temp sensor downstream of the box.

    Name:  IMG_20190703_120150.jpg
Views: 2367
Size:  97.9 KB


    Am I missing anything Any advice from folks who have done this before?

  2. #2
    Join Date
    Mar 2019
    Location
    Texas
    Posts
    171
    Post Likes
    Quote Originally Posted by oncloud9 View Post
    Starting a new project in our office. We're doing a demo and as part of it, I'm planning to convert some old-ish VAV boxes with KMC CSC-2003 pneumatic controllers to wireless DDC controllers. Seems simple right?

    I am planning to:
    -pull off the KMC controller and pop the new controller actuator onto the shaft of the existing damper.
    - I think I can reuse the pressure ports and hook the tubes to the pressure inlet of the new controller. Not exactly sure what type of flow measurement is in the existing box.
    - Run 24V power to the new controller
    - Not going to be using the hot water coils (VRF retrofit) so the hot water valve will just be abandoned in place.
    - I might add a SA temp sensor downstream of the box.

    Name:  IMG_20190703_120150.jpg
Views: 2367
Size:  97.9 KB


    Am I missing anything Any advice from folks who have done this before?
    If you are reusing the inlet cross flow I would recommend blowing air into the tubes during the retrofit. This will help clean out any debris that has collected in the holes over the years and give you a better flow reading after retrofit. You can use an air compressor but I found cans of computer cleaning to be easiest. Just a quick shot in the low and high side and done.


    Sent from my iPhone using Tapatalk

  3. #3
    Join Date
    Dec 2006
    Location
    What? Who? Where?
    Posts
    2,634
    Post Likes
    If your running power to the new controllers why not also run communications? Wireless is cool but adds a level of complexity and potential issues in the future.

    kontrol out
    "Good" - Jocko
    "Open is as open does." - Forrest Gump
    "Can't we all just get a Lon?" - Garry Jack
    "BACnet: integration or interrogation?" - The Janitor
    "Interoperability? You can't handle interoperability!" - Nathan R. Jessup
    “What’s that? Aaa… open protocols? Don’t talk about…. open protocols? Are you kidding me? Open protocols? I just hope we can hardwire an interface!” - Jim Mora Watch it here!

  4. #4
    Join Date
    Aug 2014
    Location
    DMV
    Posts
    90
    Post Likes
    Agree with kontrol and MP. Wireless is only a last resort. If you are pulling power, pull the comm wire. Cable cost is nothing compared to the headache during commission and continuing service.

  5. #5
    Join Date
    May 2019
    Posts
    4
    Post Likes
    Thread Starter
    thanks for the tip unonut!

    Re: wireless-- part of the point of the project is to demonstrate/test some wireless controllers so we can convince ourselves how reliable (or not!) they are and whether we could save on cable install and recommend them for future projects.

  6. #6
    Join Date
    Apr 2007
    Location
    North Texas
    Posts
    1,144
    Post Likes
    Quote Originally Posted by oncloud9 View Post
    thanks for the tip unonut!

    Re: wireless-- part of the point of the project is to demonstrate/test some wireless controllers so we can convince ourselves how reliable (or not!) they are and whether we could save on cable install and recommend them for future projects.
    What wireless mfg. are you going with?
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  7. #7
    Join Date
    May 2019
    Posts
    4
    Post Likes
    Thread Starter
    Planning to start with the Schneider MPM-VA and the MPM-UN.

  8. #8
    Join Date
    Dec 2006
    Location
    What? Who? Where?
    Posts
    2,634
    Post Likes
    I installed approx 100 Schnieder/Andover heatpump split systems and rooftop units. Requires 4 wireless routers to pick up all the controllers due to at the time each one only supported 32 controllers. Worked, but the additional cost of the extra routers and wireless transceivers washed the cost savings on install. As it was a retro on an occupied building the client wanted minimal disturbance so the wireless was the best option. The building was right opposite one of the busiest airports in the country and we were initially concerned with interference from the radar and all the radio transmissions but never noticed any.

    kontrol out
    "Good" - Jocko
    "Open is as open does." - Forrest Gump
    "Can't we all just get a Lon?" - Garry Jack
    "BACnet: integration or interrogation?" - The Janitor
    "Interoperability? You can't handle interoperability!" - Nathan R. Jessup
    “What’s that? Aaa… open protocols? Don’t talk about…. open protocols? Are you kidding me? Open protocols? I just hope we can hardwire an interface!” - Jim Mora Watch it here!

  9. #9
    Join Date
    May 2009
    Location
    SC
    Posts
    4,047
    Post Likes
    Quote Originally Posted by oncloud9 View Post
    Planning to start with the Schneider MPM-VA and the MPM-UN.
    Via Zigbee?

    My understanding on the limitation with MPM and going wireless Zigbee between them is you won't be able to change programming or update firmware for controllers that are not connected to Ethernet. Also not sure but I think config backups of those won't work either. Ask your vendor some pointed questions on this, I might not have the right info here.

    Edit, I'll also note that firmware updates on these are SLOW. So in addition to going around and plugging into one you have to wait ~15 minutes for it to complete, each controller.

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •