HP/Air Handler Run Time

[burnselk]

Could someone tell me how long my old Carrier 2.5 ton 20kw HVAC system should run when it kicks on? It uses the old freon of course.......not the 410 A or whatever the new one is.

It's a tad old (1984 model) but seems to work just fine after I installed a new heat pump (fan and compressor) motor yesterday.

But I got to thinking about the run times and was wondering if they should be in this range: unit kicks on, runs for about 9 or 10 minutes then kicks off again.........I checked this run time for about an hour and it "runs" about the same amount of time as it is "off".

Wondering, thanks

[paul52446m]

Could someone tell me how long my old Carrier 2.5 ton 20kw HVAC system should run when it kicks on? It uses the old freon of course.......not the 410 A or whatever the new one is.

It's a tad old (1984 model) but seems to work just fine after I installed a new heat pump (fan and compressor) motor yesterday.

But I got to thinking about the run times and was wondering if they should be in this range: unit kicks on, runs for about 9 or 10 minutes then kicks off again.........I checked this run time for about an hour and it "runs" about the same amount of time as it is "off".

Wondering, thanks

Run time of a unit depends on heat loss of the home, how hot you set the temp. indoors, what the temp is outside. If a unit is sized about right , in the real cold it will run almost full time. So your run time depends on all these factors, and how it is sized for your home and your area. You also have factors like keeping your coils clean and a clean filter. Later Paul

[burnselk]

Paul, do you think my HVAC is at least within a decent range? In other words, if I set my in home thermostat to a half of a degree lower than the house is already should it only run a short period of time? Is this a correct assumption.

Could I check the unit to see it's going to run for a longer time by turning the AC down about 3 degrees lower than the thermostat is showing the temp in the house to be? Would that make it run longer? Seems to me it would.....or am I just barking up a tree?

Thanks Paul.

[paul52446m]

Paul, do you think my HVAC is at least within a decent range? In other words, if I set my in home thermostat to a half of a degree lower than the house is already should it only run a short period of time? Is this a correct assumption.

Could I check the unit to see it's going to run for a longer time by turning the AC down about 3 degrees lower than the thermostat is showing the temp in the house to be? Would that make it run longer? Seems to me it would.....or am I just barking up a tree?

Thanks Paul.

Yes is you turn a stat. down 1/2 degree it will run a shorter time than it will
if you turn it down 3 degrees.
I don't know what stat. you have, but a lot of stats. have a heat anticpator that we adjust by the amps. going through the stat. I want the temp in the home
to not drop more than 1/2 to 1 degree before the heat comes back on.
Most stats are not adjustable on the cooling side, They will drop about 1 degree below set temp before they turn off. later paul

[burnselk]

Thanks Paul, it appears my mercury stat is working fine.

My stat is an old Carrier type (came with the 1984 model unit) with Fan on and Fan off slide switch on the bottom left and Aux., On, and Off slide switche on the right bottom.........the separate Temp. (on left) and Cooling (on right) levers are on the top.