I recently have installed a Lennox XC15 and was wondering whether I
should have the A/C constantly going even when nobody's home during
the day or have it not come on until shortly before we get home from
I currently have the thermostat programmed so that the A/C will not
come on after we leave for work and have it come back on to start
cooling down the house shortly before we come back from work.
But what I noticed on my couple of days off from work is that during
the day when it's not programmed to come on at all and is hot out, my
house can reach as high as 30C/86F inside. Then when it came time to
cool down the house, the A/C was going for quite a while before it
brought the indoor temperature down to 24C/75F which is what we're
So, what I was wondering was, which would be a more efficient and less
taxing use of the A/C?
1. Have the A/C not come on during the day at all after we leave for
work until we come home, no matter how hot it gets inside, thereby
having the A/C run for quite a while before the indoor temperature is
brought down to 24C/75F.
2. Do have the A/C keep the house cool, but just not at 24C/75F, which
is what we normally have the house at. But a little warmer while
nobody's home, say 26C/78.8F. And then have the A/C cool down the
house to our comfortable 24C/75F by the time we get home from work.
3. Have the A/C running all the time to keep the house at the 24C/75F
level whether nobody's home or not.
FYI, I believe my A/C has a SEER rating of 15 or so. How do you guys
have your A/C programmed? Thanks.