Most of the new high SEER rated AC units have larger condensing coils, and
smaller compressors, and matching with a large inside coil.
We have have added a secondary condensing coil to our units, with solar
operated fan. The secondary coil was from an old 3 ton unit (obtained for
free). The compressor and fan were removed, and then connected in line with
exiting condensing coil. The head pressure was reduced significantly and
AMP usage dropped 2-3 amps. Other things we did were run the high and low
side lines together and insulated heavily from condensing unit to
evaporator. The low side (cold will help cool down high side line. Recommend
insulating both lines, attics are hot and will effect high side line. We
are also adding a water cooling unit (simple heat exchanger) which obtains
water from the drain pan in attic, the water is already chilled and cools
down high side. After running through exchanger, water is diverted to
On 4/15/06 4:39 PM, "Todd" <toddt58@...> wrote:
> Ooops. I forgot to mention the AC unit mist cooling idea.
> My building has two AC units: one for the office area downstairs and
> one for my loft apartment upstairs. My loft already has enough
> ceiling and roof insulation to rule out using the evaporative
> cooling idea on the flat roof surface, but the AC unit is up there.
> Last year I installed a shade screen on the South and West sides,
> open on the bottom 18" for air intake and open on the top for
> This year I want to add a water mist to cool off the outside unit.
> I've heard folks talk about a solenoid triggered off the 24v signal
> from the thermostat to the outside fan unit. Basically, when the
> outside unit is running, the water is spraying.
> The idea is to cool the outside unit by evaporation, thus lowering
> the head pressure and supposedly lowering the AC air temp inside.
> Does the Central AC have enough 24v signal strength to add a
> solenoid valve to it... to control the water flow?
> What size mist heads? Do I need to go as low as a .5gph or .75gph
> like the mist cooling systems use?
> I plan to add a 200 line filter and have seen the phosphate
> cartridges to prevent scale buildup on the AC unit. Suggestions?
> By the way, I applied white mobile home roof coating years ago and
> it made a tremendous difference.
> Yahoo! Groups Links
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