bkspero
Member
We recently had a 5 ton single stage AC replaced with a 2 stage 4 ton AC unit. The contractor based the 4 ton recommendation on his heat/cooling load calculation where the others had quoted 5 ton units based on the existing equipment.
So far we've been very pleased. The first 3 days of operation were about as hot and humid as it gets here (95-99F and 75% RH), and the AC operated in the 2nd stage probably 70% of the time and stage 1 the rest. After that the temperature has moderated to the 80-90F range with ca. 40-50% RH, and the unit has kept the house at our setpoint (76F) with stage 1 operation exclusively.
As always, our second floor is warmer than the first in the summer, but the difference is small when the AC is operating continuously. During stage 1 intermittent operation we run the air handler fan when the AC is off and it substantially eliminates the temperature differences.
So overall we've been happy with the change to a smaller 2 stage AC system. It has kept the house comfortable, runs a greater percentage of the time so room temperature and humidity have been less variable, it is quieter (on stage 1), and, presumably, since it is a smaller unit running mostly on its more efficient stage 1, has cost less to keep the house comfortable.
So far we've been very pleased. The first 3 days of operation were about as hot and humid as it gets here (95-99F and 75% RH), and the AC operated in the 2nd stage probably 70% of the time and stage 1 the rest. After that the temperature has moderated to the 80-90F range with ca. 40-50% RH, and the unit has kept the house at our setpoint (76F) with stage 1 operation exclusively.
As always, our second floor is warmer than the first in the summer, but the difference is small when the AC is operating continuously. During stage 1 intermittent operation we run the air handler fan when the AC is off and it substantially eliminates the temperature differences.
So overall we've been happy with the change to a smaller 2 stage AC system. It has kept the house comfortable, runs a greater percentage of the time so room temperature and humidity have been less variable, it is quieter (on stage 1), and, presumably, since it is a smaller unit running mostly on its more efficient stage 1, has cost less to keep the house comfortable.