Took time to attend to this Sat. evening, as it had been about 2yrs. (I think). I usually do it once/yr. My unit is an upflow, located in the living-space closet, so access is easy.
There was a bit of mold on it, as well as some dirt that had balled up due to being wetted. Completely sealing the return air plenum decades ago means only filtered air now gets to the coil.
I sprayed down both inner sides of the A-frame evaporator coil with TuffStuff, then let it soak for 15 min. TF works great as it foams up inside the coil, thoroughly wetting all inner surfaces. Plus it contains the same ingredients as the other "pro" canned cleaners...at 1/4 the price. I then pulled the residue down to the bottom with a stiff brush.
I then rinsed it down with a couple gallons of softened water as I was clean out of distilled. The squirrel cage looked fine: Just a very thin layer of dust on it.
What's interesting is the difference in indoor humidity removal. Before, it was fine as the house stays at about 44% Rh, despite the high humidities of late.
Post cleaning though, the indoor Rh has dropped even lower to 35%! As I type, these are the conditions:
Outdoor ambient: 84°F
Outdoor Dew Point: 75°F
Outdoor Rh: 73%
Heat Index: 93°F
Indoor temp: 78°F
Indoor Rh: 35%
Delta-T across the coil is about 20°F
Early evening until mid-morning, the t-stat = 77°F. Then it's raised to 82°F. I've noticed that the indoor temp will rise about 1°/hr or so later on, then level off. Indoors it feels very comfortable and dry, compared to outdoors, even with the higher temp setting during the day.
When I walk in from outdoors, I can really feel the humidity just fly off my skin, hair, clothes, etc. as it immediately begins to evaporate.
This level of performance from a now 26yr old Janitrol unit!
I doubt it would have lasted this long without removing the flow rater and upgrading to a Sporlan TXV back in the mid-90's, as a TXV is just a superior refrigerant metering device. I also had a sight glass installed just before it so I could keep an eye on refrigerant levels.
I also designed & installed a new duct system based on both Man J & D calculations. The unit has become a bit oversized due to the "tightening" of the house + additional insulation + new shingles. The former duct system was woefully inadequate, far too restrictive and created too much turbulence. Plus it couldn't be properly balanced.
The fan is currently set on LOW as it creates to much suction on the return side, bowing in the 20x24 filter. Even a new filter bows a bit on LOW. I cut in an additional 144 sqr. in. of return air to allieviate this, but now think I'll go with a 20 x 30 x 2" return air filter. (The original installers must have run out of 20x25 grille frames and found the x24 somewhere. So I got stuck with it).
Here, latent heat removal is just as important as sensible, due to our high dew points. Humidity removal depends on a cold, clean evap. coil and sufficient airflow through it.
There was a bit of mold on it, as well as some dirt that had balled up due to being wetted. Completely sealing the return air plenum decades ago means only filtered air now gets to the coil.
I sprayed down both inner sides of the A-frame evaporator coil with TuffStuff, then let it soak for 15 min. TF works great as it foams up inside the coil, thoroughly wetting all inner surfaces. Plus it contains the same ingredients as the other "pro" canned cleaners...at 1/4 the price. I then pulled the residue down to the bottom with a stiff brush.
I then rinsed it down with a couple gallons of softened water as I was clean out of distilled. The squirrel cage looked fine: Just a very thin layer of dust on it.
What's interesting is the difference in indoor humidity removal. Before, it was fine as the house stays at about 44% Rh, despite the high humidities of late.
Post cleaning though, the indoor Rh has dropped even lower to 35%! As I type, these are the conditions:
Outdoor ambient: 84°F
Outdoor Dew Point: 75°F
Outdoor Rh: 73%
Heat Index: 93°F
Indoor temp: 78°F
Indoor Rh: 35%
Delta-T across the coil is about 20°F
Early evening until mid-morning, the t-stat = 77°F. Then it's raised to 82°F. I've noticed that the indoor temp will rise about 1°/hr or so later on, then level off. Indoors it feels very comfortable and dry, compared to outdoors, even with the higher temp setting during the day.
When I walk in from outdoors, I can really feel the humidity just fly off my skin, hair, clothes, etc. as it immediately begins to evaporate.
This level of performance from a now 26yr old Janitrol unit!
I doubt it would have lasted this long without removing the flow rater and upgrading to a Sporlan TXV back in the mid-90's, as a TXV is just a superior refrigerant metering device. I also had a sight glass installed just before it so I could keep an eye on refrigerant levels.
I also designed & installed a new duct system based on both Man J & D calculations. The unit has become a bit oversized due to the "tightening" of the house + additional insulation + new shingles. The former duct system was woefully inadequate, far too restrictive and created too much turbulence. Plus it couldn't be properly balanced.
The fan is currently set on LOW as it creates to much suction on the return side, bowing in the 20x24 filter. Even a new filter bows a bit on LOW. I cut in an additional 144 sqr. in. of return air to allieviate this, but now think I'll go with a 20 x 30 x 2" return air filter. (The original installers must have run out of 20x25 grille frames and found the x24 somewhere. So I got stuck with it).
Here, latent heat removal is just as important as sensible, due to our high dew points. Humidity removal depends on a cold, clean evap. coil and sufficient airflow through it.