I had a service tech out at my house yesterday working on my equipment and while talking to him one of the things he mentioned was that I should run my furnace fan maybe a half hour every hour to help evenly distribute the air throughout the house. I live in the north east where it is very humid right now so wouldn’t running the The fan throw that moisture back into the house making it more humid? Is this normally a suggestion to help evenly distribute the air? I’m trying to get the upstairs a little cooler. Thank you
Continuously running the fan
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Fitter30
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A running ac the evaporator coil RH 100% running the fan will put some back into the house till the coil dries. Condensate drain pans don't hold much water since there usually on the positive side of the blower. Running the fan in the on position will help adjusting grills might help.
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Yes, do run the fan, better yet replace your thermostat with a smart one. You want to pull that heat off the second floor and mix it with the cooler air below.
I run mine via thermostat program minimum of 35 minutes per hour. I live in humid central Florida in a two story home. The air handler is on the second floor (not the attic) that handles the entire home. The problem with a two story home for AC is when the ac is not running, all the heat of the home goes up to the second floor and usually it's warmer than the first floor. Summer time it is not so bad because the AC is running a good portion of the time anyway but at night it runs less and the heat builds up.
I have a Honeywell WiFi Smart thermostat, model TH9320WF5003. It has a "circulate" fan setting and I leave it there most of the time. Honeywell's documentation reads that the fan will run at least 35 minutes including cooling and heat mode per hour. When the fan is running during the circulate time frame, the AC or heat will cycle on and off as needed. It keeps the both floors fairly even in temperature.
Running the fan does not make the home more humid. Right now the outdoor humidity is 69%, temp 85 and it is 6:30PM in Orlando, FL, my indoor humidity is 48%. Typical for this time of the year. Do check the drip pan as it can build up with mold. Keep the condensate line clean and flush it once or twice a year. Spray on coil cleaner and allow the condensate to flush it away. The coils drain easily and water will lay in the drip pan but it would take a long time and a lot of heat for the water to evaporate and into your home.
If the home is warm and you only turn on the fan, the warm air near the ceiling will get pushed around or sucked in the returns and it might feel like it's making it more warm & humid. Keep it in "cool" mode and keep the temperature about the same 24/7. Turning up the thermostat so the AC runs less when you are not home does not save energy or money and the humidity increases. When you return, say after work, everything is the home must be cooled down, that is walls, floors, furniture, etc., and the AC runs longer and harder. If you plan to be away for more than two days, then do raise the thermostat some but not so much where humidity can build up past 60%.
Just this past few weeks the outside temp is over 90 degrees everyday. I set the temperature at 77 and most of the time the home is very comfortable. As its gets hotter outside the AC runs longer, drying the air, but then it feels fairly cool inside the home and the wife puts on a sweater. I'll turn it up to 78. Most snow belt folks cannot fathom how the home can be left at 77 during the summer and feel comfortable. I'm living in Florida for 30 years.
I run mine via thermostat program minimum of 35 minutes per hour. I live in humid central Florida in a two story home. The air handler is on the second floor (not the attic) that handles the entire home. The problem with a two story home for AC is when the ac is not running, all the heat of the home goes up to the second floor and usually it's warmer than the first floor. Summer time it is not so bad because the AC is running a good portion of the time anyway but at night it runs less and the heat builds up.
I have a Honeywell WiFi Smart thermostat, model TH9320WF5003. It has a "circulate" fan setting and I leave it there most of the time. Honeywell's documentation reads that the fan will run at least 35 minutes including cooling and heat mode per hour. When the fan is running during the circulate time frame, the AC or heat will cycle on and off as needed. It keeps the both floors fairly even in temperature.
Running the fan does not make the home more humid. Right now the outdoor humidity is 69%, temp 85 and it is 6:30PM in Orlando, FL, my indoor humidity is 48%. Typical for this time of the year. Do check the drip pan as it can build up with mold. Keep the condensate line clean and flush it once or twice a year. Spray on coil cleaner and allow the condensate to flush it away. The coils drain easily and water will lay in the drip pan but it would take a long time and a lot of heat for the water to evaporate and into your home.
If the home is warm and you only turn on the fan, the warm air near the ceiling will get pushed around or sucked in the returns and it might feel like it's making it more warm & humid. Keep it in "cool" mode and keep the temperature about the same 24/7. Turning up the thermostat so the AC runs less when you are not home does not save energy or money and the humidity increases. When you return, say after work, everything is the home must be cooled down, that is walls, floors, furniture, etc., and the AC runs longer and harder. If you plan to be away for more than two days, then do raise the thermostat some but not so much where humidity can build up past 60%.
Just this past few weeks the outside temp is over 90 degrees everyday. I set the temperature at 77 and most of the time the home is very comfortable. As its gets hotter outside the AC runs longer, drying the air, but then it feels fairly cool inside the home and the wife puts on a sweater. I'll turn it up to 78. Most snow belt folks cannot fathom how the home can be left at 77 during the summer and feel comfortable. I'm living in Florida for 30 years.
Running the fan continuously CAN increase the summertime indoor humidity if the ducts aren't well balanced (with a correctly sized return for every doored-off room with a supply register) &/or the the house is air leaky. For duct heat/coolth delivery to happen pressures are induced in the ducts, and if a room is pressurized or depressurized relative to the outdoors it drives outdoor air infiltration. With a properly balanced duct system the pressure differences are small, and the air handler driven infiltration levels are small.
An Energy Star duct system would measure <3 pascals (0.012" water column)pressure differences between rooms under all operating conditions, doors open or closed. Most pre-existing duct systems will fail this test.
Only if the system is way oversized (sadly an all to common issue) would the re-evaporation of the moisture off the coils come in to play. This is really a "failure to dehumidify" problem rather than adding-moisture problem. In general right-sizing the equipment (or better still, right sizing MODULATING equipment that runs almost continuously) does a better job of both cooling the upper floors and keeping humidity levels bounded.
Running the blower continuously also chews through electricity adding HEAT to the house rather than cooling it. With properly designed ducts and running at low speed an ECM blower can run continuously without a significant heating effect.
If yours is a not-so-smart oversized 1 or 2 stage system you may get better bang/buck out of one of the U-shaped modulating Midea window-shakers for auxiliary cooling upstairs. The 1-tonner only uses ~100 watts when running at it's minimum compressor & fan speeds in normal cooling mode (that is a fraction of the blower power on a central air handler), but pulls about 1100 watts when ramped up to full tilt (which won't happen if your central air is designed reasonably and running.) For those days when the sensible cooling loads are low it can be run in "DRY" mode, where it draws 300-500 watts (about the same as a high efficiency blower on a whole house system), but rather than heating the places it's removing humidity and doing at least some sensible cooling with that power. This is how I'm currently dealing with humidity & comfort issues the ludicrously oversized 1-speed low efficiency central air (a ~10 SEER 5 tonner for a <2 ton 1% design load) that never runs long enough to really cool the upstairs. At 15 CEER this quiet modulating window shaker is more efficient than a code-min efficiency central air unit too, and with no ducts to balance, it isn't driving infiltration.
They aren't cheap. In short supply earlier in the summer and there was and still is a lot of price gouging going on. I was looking for the 8000 BTU/hr unit, but found a 12,000BTU/hr unit online for less money than what the Walton family was (and still is) gouging for the 8000 at their box stores. (MSRP is ~$350 on the 8K, ~$450 on the 12K.)
An Energy Star duct system would measure <3 pascals (0.012" water column)pressure differences between rooms under all operating conditions, doors open or closed. Most pre-existing duct systems will fail this test.
Only if the system is way oversized (sadly an all to common issue) would the re-evaporation of the moisture off the coils come in to play. This is really a "failure to dehumidify" problem rather than adding-moisture problem. In general right-sizing the equipment (or better still, right sizing MODULATING equipment that runs almost continuously) does a better job of both cooling the upper floors and keeping humidity levels bounded.
Running the blower continuously also chews through electricity adding HEAT to the house rather than cooling it. With properly designed ducts and running at low speed an ECM blower can run continuously without a significant heating effect.
If yours is a not-so-smart oversized 1 or 2 stage system you may get better bang/buck out of one of the U-shaped modulating Midea window-shakers for auxiliary cooling upstairs. The 1-tonner only uses ~100 watts when running at it's minimum compressor & fan speeds in normal cooling mode (that is a fraction of the blower power on a central air handler), but pulls about 1100 watts when ramped up to full tilt (which won't happen if your central air is designed reasonably and running.) For those days when the sensible cooling loads are low it can be run in "DRY" mode, where it draws 300-500 watts (about the same as a high efficiency blower on a whole house system), but rather than heating the places it's removing humidity and doing at least some sensible cooling with that power. This is how I'm currently dealing with humidity & comfort issues the ludicrously oversized 1-speed low efficiency central air (a ~10 SEER 5 tonner for a <2 ton 1% design load) that never runs long enough to really cool the upstairs. At 15 CEER this quiet modulating window shaker is more efficient than a code-min efficiency central air unit too, and with no ducts to balance, it isn't driving infiltration.
They aren't cheap. In short supply earlier in the summer and there was and still is a lot of price gouging going on. I was looking for the 8000 BTU/hr unit, but found a 12,000BTU/hr unit online for less money than what the Walton family was (and still is) gouging for the 8000 at their box stores. (MSRP is ~$350 on the 8K, ~$450 on the 12K.)
