Hello,
I had a 3.5 ton single phase unit installed in March. I cant put my finger on it but I have this feeling it is not more efficient than the previous 19 year old unit and possibly using more power. A tech has recently looked at it and said static pressure was .41. He also said my subcooling was 1 and needed to be between 5 and 7. I then had the installer come out and he said subcooling was fine. My split at plenum and return is 20-21 in early morning and night and 19 during the day
When I called the field manager of the tech who said subcooling was low he said based on your split his reading must be wrong, so he didnt suggest more freon. So I now wonder if the static pressure reading was wrong too
I have an overhead return from hot attic and a direct return from the house so my return temp is blended. On past 90 degree days the overhead return is 84.4 degrees and direct is 79, the temp we keep the house at. The plenum temp is 61. Due to the blended return temp the split is at least 19 on a hot day
Yesterday I checked the plenum temp after running for at least 10 minutes and it was 63.6. The vents in the house were a couple degrees warmer than normal too. The temp outside was 89/90.
I checked plenum a few minutes later and it was 62.3. This was after running for at least 15 minutes
It started raining so temp outside cooled down and on next cycle plenum was 61. Later that night, 9:30 pm, plenum was 59.
I used a lot of energy in the house yesterday and I have never measured 63.6 at the plenum before. Can the overhead return cause fluctuations in the plenum temp? Can there be a wiring issue causing the unit to use more power than necessary?
Something isnt right but two people have been out here. Is it possible for something else to cause fluctuations in plenum temp? My two concerns are power consumption and temp out of plenum. Thanks
I had a 3.5 ton single phase unit installed in March. I cant put my finger on it but I have this feeling it is not more efficient than the previous 19 year old unit and possibly using more power. A tech has recently looked at it and said static pressure was .41. He also said my subcooling was 1 and needed to be between 5 and 7. I then had the installer come out and he said subcooling was fine. My split at plenum and return is 20-21 in early morning and night and 19 during the day
When I called the field manager of the tech who said subcooling was low he said based on your split his reading must be wrong, so he didnt suggest more freon. So I now wonder if the static pressure reading was wrong too
I have an overhead return from hot attic and a direct return from the house so my return temp is blended. On past 90 degree days the overhead return is 84.4 degrees and direct is 79, the temp we keep the house at. The plenum temp is 61. Due to the blended return temp the split is at least 19 on a hot day
Yesterday I checked the plenum temp after running for at least 10 minutes and it was 63.6. The vents in the house were a couple degrees warmer than normal too. The temp outside was 89/90.
I checked plenum a few minutes later and it was 62.3. This was after running for at least 15 minutes
It started raining so temp outside cooled down and on next cycle plenum was 61. Later that night, 9:30 pm, plenum was 59.
I used a lot of energy in the house yesterday and I have never measured 63.6 at the plenum before. Can the overhead return cause fluctuations in the plenum temp? Can there be a wiring issue causing the unit to use more power than necessary?
Something isnt right but two people have been out here. Is it possible for something else to cause fluctuations in plenum temp? My two concerns are power consumption and temp out of plenum. Thanks
