Results 1 to 9 of 9
  1. #1
    Join Date
    Sep 2019
    Posts
    2
    Post Likes

    Chiller + Boiler 4 pipe induction system setup

    Hi Guys,
    First time posting but Iím scratching my head on as to why this building setup there mechanicals this way. Brand new build out last two years constantly having issues with rooms being too cold in the summer and winter. It is a 4 pipe induction coil system. Typically Iíve seen 2 way control valves on supply and return sides chiller and boiler. The way this building did it was on the supply chiller (A) and boiler (B) side of the induction coil they used a 3 way valve that supplies the coil (AB) and on the return they did the regular 2 way valve on chiller return (A) and boiler (B). Upon looking at controls used I found that the 3 way setup makes it a mixing valve and not a diverting valve. My question is that in summer/winter months when valve is moving is it possible supply (A) or (B) is feeding the other system when not operating? From looking at how things are setup there are so many variables that will make the system never work correctly. I would also like to add that the building has terrible humidity issues which I found a lot of rtus are in negative pressure but I was also wondering what is the ideal chiller temp for induction coils so there is less condensation and can still cool down a room?
    Thanks for any input

  2. #2
    Join Date
    Feb 2016
    Location
    Louisburg Kansas
    Posts
    3,446
    Post Likes
    Hire a balance contractor that knows what they are doing. Ask several design engineers who is the best and don't argue price. He should be able to tell you anything you need to know and make it work right or explain why it won't.
    These systems are not complicated but you have to know what you are doing.
    No man can be both ignorant and free.
    Thomas Jefferson

  3. #3
    Join Date
    Sep 2019
    Posts
    2
    Post Likes
    Thread Starter
    As much as I agree with you Iím looking over the plans that a previous engineer made up and getting eyes on what was done so I can go into a meeting and explain why what was done wonít work correctly. Which will help me in getting another engineer needs to come in so we can rectify the issue. Iím pretty sure I see whatís going on but I came here to ask just to make sure I wasnít missing something as to why it was done that way. Also just so you know because Iím sensing some hostility in the reply Iím a licensed refrigeration tech whose been managing commercial building the last 7 years and have never come across this setup. Iíve looked extensively on any application for a four pipe to have this setup and have found nothing. Thatís why I was hoping for someone to be able to answer me or point me in the write direction.

  4. #4
    Join Date
    Dec 2014
    Location
    New Mexico
    Posts
    970
    Post Likes
    Dose the piping feed one coil or two coils. Single coil in the past a lot of the time used a heat recovery heat exchanger on the chiller to add head to the heating loop.


    Sent from my iPhone using Tapatalk

  5. #5
    Join Date
    Feb 2016
    Location
    Louisburg Kansas
    Posts
    3,446
    Post Likes
    Nahas there is no hostility whatsoever in my reply. I spent 25 years designing these systems and another 20 years balancing them. I understand what you are trying to do but we can't help you a lot from you or anyone else describing it because there are too many details and possibilities.
    I balanced a large primary/secondary heating water system that had one area that wouldn't heat at all. What I found was a double secondary loop that was recirculating water that had already had most of the heat removed. There was a booster pump on this circuit that was seriously undersized and couldn't deliver enough water to the area if the water contained enough heat to do the job. That is just one example of what can happen that we cannot see here.
    I'm assuming you may very well know the root of the problem but your argument will be a lot more convincing if you back it up with certified test results. If the building is as bad as you have indicated I'm at a loss as to why you have to prove your case but that happens if your dealing with penny pinchers.
    No man can be both ignorant and free.
    Thomas Jefferson

  6. #6
    Join Date
    May 2018
    Location
    VA/DC
    Posts
    248
    Post Likes
    Quote Originally Posted by Nadeam Nahas View Post
    Hi Guys,
    First time posting but Iím scratching my head on as to why this building setup there mechanicals this way. Brand new build out last two years constantly having issues with rooms being too cold in the summer and winter. It is a 4 pipe induction coil system. Typically Iíve seen 2 way control valves on supply and return sides chiller and boiler. The way this building did it was on the supply chiller (A) and boiler (B) side of the induction coil they used a 3 way valve that supplies the coil (AB) and on the return they did the regular 2 way valve on chiller return (A) and boiler (B). Upon looking at controls used I found that the 3 way setup makes it a mixing valve and not a diverting valve. My question is that in summer/winter months when valve is moving is it possible supply (A) or (B) is feeding the other system when not operating? From looking at how things are setup there are so many variables that will make the system never work correctly. I would also like to add that the building has terrible humidity issues which I found a lot of rtus are in negative pressure but I was also wondering what is the ideal chiller temp for induction coils so there is less condensation and can still cool down a room?
    Thanks for any input
    so I understand you correctly. there is a chiller supply and return. boiler supply and return. and they both feed a single coil. Sounds like they are using the 3 way as a flow control to match the space load which is why the chilled and heated have a 2 way shut off. This does allow the two water systems to be as one. So each system needs to be set at the same water pressure. Reducing condensation by raising chilled water temp reduces the ability to dehumidify,

    How did you observe the valves being controlled.

  7. #7
    Join Date
    Nov 2011
    Location
    East Side
    Posts
    6,700
    Post Likes
    What is an induction system? Plate and frame?

  8. #8
    Join Date
    May 2018
    Location
    VA/DC
    Posts
    248
    Post Likes
    his description sounds like a fan coil to me.

  9. #9
    Join Date
    Aug 2000
    Location
    Under my tree
    Posts
    5,133
    Post Likes
    If these are true "induction" boxes they may never work. I have yet to see this type of setup work properly.
    To much work with too little time!!!!

Posting Permissions

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