Page 1 of 2 12 LastLast
Results 1 to 13 of 19

Thread: RTU

  1. #1
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,843

    RTU

    Maybe this duct work has a purpose. I don't know! And the misting system? Maintenace guy said unit is now putting out 4 lower supply temps.
    Attached Images Attached Images     

  2. #2
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    1,973
    My old company was once in an older, newly renovated building. Office workers complained about a bad odor. When I went up on the flat, gravel covered roof, I was shocked and disgusted at all the bird crap that was up there. I just shut and disabled the outside air economizers . Perhaps if I had been more creative I would have thought of such a solution as that ductwork. As far as that other device, I'm not exactly sure from the pics what that is. Google, here I come....

  3. #3
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    1,973
    Ok, the thing on top had me wondering. I see now it is the "control box". At least they acknowlege the effect of minerals on the coil. Still, others will have to use their units to prove to me that no harm is being done to the unit. I'll pass.

  4. #4
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,843
    Quote Originally Posted by Nuclrchiller View Post
    As far as that other device, I'm not exactly sure from the pics what that is.
    It's a "handwasher" for HVAC service techs like myself!

  5. #5
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,843
    Quote Originally Posted by Nuclrchiller View Post
    Ok, the thing on top had me wondering. I see now it is the "control box". At least they acknowlege the effect of minerals on the coil. Still, others will have to use their units to prove to me that no harm is being done to the unit. I'll pass.
    The customer is testing it on 2 units right now. They have a total of 48 RTU's on that building.

  6. #6
    Join Date
    May 2007
    Location
    South East GA
    Posts
    12
    I see they are Selling this thing for $490.00 EACH! 4 AA batteries included. What a deal!
    I have never seen this before but I have seen people useing garden hose on top of roofs to lower there cooling bill (Right) cut there cooling bill by $5.00 but raise there water bill $500.00

  7. #7
    Join Date
    Aug 2009
    Location
    Jurupa Valley, CA
    Posts
    1,645
    Quote Originally Posted by southeasterntec View Post
    I see they are Selling this thing for $490.00 EACH! 4 AA batteries included. What a deal!
    I have never seen this before but I have seen people useing garden hose on top of roofs to lower there cooling bill (Right) cut there cooling bill by $5.00 but raise there water bill $500.00
    Playing a bit of devil's advocate, but equipment damage aside, the water systems can save a ton of money on operations cost - depending on the climate. In a dry climate, they will result in a MUCH lower head pressure. The only problem with retrofitting them on systems not designed for it (like here) is that it has the potential to eat up the condenser coil. There is technical merit behind the theory, just a trade-off with either maintenance cost, or equipment life. Using soft water would greatly reduce the equipment damage potential.

    Keep in mind, they DO make evaporative condenser based RTU's, which is basically what this is - it's just the ones designed for it are designed to withstand the potential damage the water might provide.

    A 'better' way to handle the evaporative add-on is to do it remotely. Not misting directly on the unit, but using basically a swamp cooler type system to ducted to discharge the much lower dry bulb air on the condenser, without actually wetting it.

  8. #8
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,843
    Quote Originally Posted by CraziFuzzy View Post

    A 'better' way to handle the evaporative add-on is to do it remotely. Not misting directly on the unit, but using basically a swamp cooler type system to ducted to discharge the much lower dry bulb air on the condenser, without actually wetting it.

    Yeah, we got a customer thats running cellulose pads on various large carrier RTU's. The wet section is made of stainless steel w/ temperature activated water pump. We replaced the pads not too long ago and the condensor's didn't look bad at all. Mainly just dusty and no calcium build up at all and they do run at a much lower head pressure.

  9. #9
    Join Date
    Jan 2010
    Posts
    6,056
    Quote Originally Posted by KB Cool View Post
    Maybe this duct work has a purpose. I don't know! And the misting system? Maintenace guy said unit is now putting out 4 lower supply temps.
    I have seen those animals at the circus
    Is that control box blocking any air flow ?

  10. #10
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,843
    Quote Originally Posted by VTP99 View Post
    I have seen those animals at the circus
    Is that control box blocking any air flow ?
    I didn't do any checks on these 2 systems. But, the condensor TD didn't feel any different than a unit without it. And again, this was just using me waving my hand over the ODF after washing them!! Serious, any sort water on a big rooftop is a welcomed sight to me as it really starts to get Hot!!

  11. #11
    Join Date
    Jun 2003
    Location
    Chicago, IL
    Posts
    4,322
    i recently removed a homemade misting system from a carrier RTU. It pretty much destroyed the coil in one year. 3 bottles of CLR latter and most of the mineral buildup is off of it.

    Then I split the coil and cleaned it and theres no more problems with it tripping the breaker due to high head pressure (which was the reason that someone installed the mister)

  12. #12
    Join Date
    Jan 2010
    Posts
    6,056
    Quote Originally Posted by craig1 View Post
    i recently removed a homemade misting system from a carrier RTU. It pretty much destroyed the coil in one year. 3 bottles of CLR latter and most of the mineral buildup is off of it.

    Then I split the coil and cleaned it and theres no more problems with it tripping the breaker due to high head pressure (which was the reason that someone installed the mister)
    So you removed a band-aid did it hurt ?

  13. #13
    Join Date
    Jun 2002
    Location
    south jersey
    Posts
    1,096
    Seems like a good idea for a problem system. Would not put that on a new system. Looks like crap. Hope he did not invest his life savings on that.
    You need to put the phone down and get back to work!

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