Page 1 of 2 12 LastLast
Results 1 to 13 of 20
  1. #1
    Join Date
    Mar 2004
    Location
    Vancouver, BC
    Posts
    125
    Anyone got any comments, good, bad, or indifferent regarding these types of distributed DX systems? Daikon, Mitsubishi, Colt, etc. are flogging these systems as the latest and greatest solution to local zone HVAC control. I have some concerns about a lot of high cost/high pressure refrigerant pipes scattered through a building in terms of risk management. They claim a higher energy efficiency, but I think a good old two-pipe water to air packaged heat pump system wouldn't be that much worse, and you're only going to be dealing with low pressure water if it leaks.

  2. #2
    Join Date
    Dec 2005
    Location
    Rockhill South Carolina
    Posts
    370
    I would rather have a ref leak above ceiling tiles than water.Almost all supermarkets are piped over head,and besides most of the time if the piping in the overhead is tight after startup it is usually trouble free.The key though is a proper startup.

  3. #3
    Join Date
    Dec 2005
    Location
    North America
    Posts
    236
    We have installed 50 or more and I have started up over a hundred by know. Mitsubushi only. The only problem is no service calls

  4. #4
    Join Date
    Jun 2002
    Posts
    48
    These type systems are only new to U.S. Been in Asia and Europe for years. As stated, proper start-up is key.
    The few people I know that work on them say service calls
    are few and far between. The efficiencies are due to the
    variable speed compressors.

  5. #5
    This is the latest technology and it is not just a lot of BS. By the way, there are few failures, but you better know your HVAC before you attempt an install or service call.

  6. #6
    Join Date
    Dec 2007
    Posts
    16
    Do have some training and info before installing.

  7. #7
    Join Date
    Mar 2003
    Posts
    7,314
    we have done Daikin systems and find them to be trouble free. The energy recovery stuff is great and allows for even better efficiency while running some zones for heating and some for cooling. One packaged unit cannot give you the flexibility of these systems. They are very common outside the US and work well.

  8. #8
    Join Date
    Jun 2008
    Location
    LONDON
    Posts
    57

    Daikin,Mitsubishi

    Quote Originally Posted by gmcd View Post
    Anyone got any comments, good, bad, or indifferent regarding these types of distributed DX systems? Daikon, Mitsubishi, Colt, etc. are flogging these systems as the latest and greatest solution to local zone HVAC control. I have some concerns about a lot of high cost/high pressure refrigerant pipes scattered through a building in terms of risk management. They claim a higher energy efficiency, but I think a good old two-pipe water to air packaged heat pump system wouldn't be that much worse, and you're only going to be dealing with low pressure water if it leaks.
    We are specialized in installation of these systems....and what i gather is that you dont have a clue ..what is happening with these higher pressures maybe that is why you posted so many " smart " words

  9. #9
    Join Date
    Oct 2001
    Posts
    6,855
    CB magazine did a full story on this new application in their September issue http://www.contractingbusiness.com/
    "when in doubt...jump it out" http://www.youtube.com/watch?v=Px5YcOeQB4I

  10. #10

    VRV off the beaten path

    I don't know how we got so far off topic, but to get back to VRV technology, the stuff is great. It is not the death of chillers and package systems, only another solution that may provide better control while saving energy. If you look at the full picture, performance, longevity, low-energy consuption, ease of installation, low maintenance cost, self diagnostics, then these systems often out perform all the other technologies.

  11. #11

    think of it as chill water

    Quote Originally Posted by gmcd View Post
    Anyone got any comments, good, bad, or indifferent regarding these types of distributed DX systems? Daikon, Mitsubishi, Colt, etc. are flogging these systems as the latest and greatest solution to local zone HVAC control. I have some concerns about a lot of high cost/high pressure refrigerant pipes scattered through a building in terms of risk management. They claim a higher energy efficiency, but I think a good old two-pipe water to air packaged heat pump system wouldn't be that much worse, and you're only going to be dealing with low pressure water if it leaks.

    The concept was born from Daikin in Japan 1982 and was a solution from the chiller group. They figured that they could move refrigerant more efficiently than water or air.
    If the piping is done correctly it is a moot point. Just remember about refrigerant density in the space. ASHRAE 15 states R 410A at a max of 25 lbs per 1000 cu ft.

  12. #12
    Are you an employee of Daikin??

  13. #13
    Join Date
    Apr 2007
    Location
    Amarillo by mornin'
    Posts
    850
    What happens when a compressor burns out!! I would like to know how you would clean up a system that is so large in piping length.
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event