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  1. Birchwood

    Removing mold from SAF

    Ran some trials. There are a few spots of obvious mold here and there on the housing, but the blades themselves have a dust colored coating about 3/8" thick, that wipes up greasy. There may not be any actual mold in that. Anyone ever seen similar?
  2. Birchwood

    Removing mold from SAF

    What we thought was sponge rubber particles flying out the registers now seems to be mold that's growing on the supply air fan and its cage in the large air handler. Any ideas on how to clean it? The fan itself seems to have a housing that we could wetvac out the bottom, if we chose to power...
  3. Birchwood

    Chill water valve arrangement

    No, the valves work in the right direction, they just don't shut off the coil circuit completely. In the summer, e.g., they regulate nicely between some cooling and a lot of cooling. Just need to be able to get them to shut off completely during most of the winter. 0% control signal equates to...
  4. Birchwood

    Chill water valve arrangement

    I thrown up two photos here, too "close quarters" to get an inclusive shot. http://www.birchy.com/GenWiki/index.php?title=Eng-tips_chill_water_valvehttp://www.birchy.com/GenWiki/index.php?title=Eng-tips_chill_water_valve
  5. Birchwood

    Chill water valve arrangement

    I ran a quick test on one of the air handlers the other day. With at least a 15 degree F temp difference between air flowing through the handler and the chilled water, withe the bypass balancing valve manually open 100% and the chill water valve set to 0% by controls, I opened up the manual...
  6. Birchwood

    Steam before cooling coil?

    We have a preheat coil, but sure can't understand when I would ever want to want waste $ by heating outside air except by mixing it with the zone air. If I'm using outside air for cooling, I'm going to use just enough to reach temp setpoint in the zone. Also, I've yet to encounter a time when...
  7. Birchwood

    Steam before cooling coil?

    Ok, since this issue can be situational, here's our situation: This air handler serves only one zone, the sanctuary of a large church with a very expensive organ. The humidifers (and most of the controls configuration) exist to keep that organ close to 50% RH. People come second, but we try to...
  8. Birchwood

    Steam before cooling coil?

    I'll call that a consensus, then. What puzzles me is that Trane built it that way, they should know better. I wonder if the design engineer forced them... or if the pieces were just assembled wrong by the installer. Thanks!
  9. Birchwood

    Chill water valve arrangement

    I'll have to "study on" your reply, but have the gist of it. I guess I will repeat the experiments with the balancing valve. It's been a year, so I don't remember how thorough I was. Thanks!
  10. Birchwood

    Chill water valve arrangement

    Our air handlers' chill water valves (under building controls) are all configured as bypass regulators. That is, when the controls send a 100% signal, the valves squeeze off the bypass, and 0% opens the bypass. This doesn't give us complete control. I estimate that when set to 0% valve position...
  11. Birchwood

    Steam before cooling coil?

    We have a large Trane air handler that was built with the steam humidifiers discharging upstream from the cooling (chilled water) coil. This results in the coil removing much of the humidity that the steam adds. Is there any possible justification? We're in Texas. About 2% of the year, we *can*...

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