Central Air Conditioning Question

I live in Ontario Canada in a 1600 sq ft home with a 2 ton central air conditioner. We normally set our thermostat to 26 degrees C but on hot days (like 30 degrees C) when the air kicks in, it can run for 2 to 3 hours before the thing shuts off. I know installing a larger system like a 3 ton might turn on and off too frequently and not remove all the humidity but I'm thinking the air shouldn't run for 2+ hours to change 2 degrees C.

Your thoughts are welcome.

does the air feel cool coming out. it should be at least 64F or around 18C coming out of the vents. has it always taken that long.

First thanks for the reply.

Yes it has always taken that long. The house is only 4 years old and we got the system installed for the second summer. We had the installer back and they checked all the vents for leaks and a good temperature coming out at the furance trunk and room vents.

The house is bungalow so there is more roof area than our previous 2 storey house. We ensure the blinds are closed to limit the greenhouse effect.

gmacpro

Did you check the filter? That could make your cooling system work harder and slower, although it shouldn't make it that slow. Maybe try kicking it up to a colder setting for 45 minutes and then readjusting it to the desired temperature and see if that helps cool the house down quicker

Thanks for the reply.

Filter is clean. As for kicking the temp up or in this case down, are you suggesting that the central air puts out more air if the temperature split is more?

gmac,

I'm thinking that TMP was under the impression that your unit was cycling, and meant to force it to stay on longer. That is not the case, is it !

Usually, AC Units are sized at 1 ton per 500 Sq Ft of floor area. Yours is undersized ! So, either get a bigger unit, or, deal with the long runs for it to get the temp right.

That's about all you can do.

Have a good Day !
S.W.

SWHouston,

Thanks very much for the reply and you've answered my question (I believe).

There seems to be several ways/methods on determining what which size unit is required to cool a certain square footage. Most will say a 2 ton will nicely cool a 1600 sq ft however for our house this doesn't appear to be the case. My thinking is increasing the output will cool the house faster and increasing the right amount will still remove the humidity from the air. Maybe a 2.5 ton will be better suited.

How does a 3 ton cool faster? Is there more air flow thru the compressor?

gmacpro

How many days above 30C do you have each year?

You have to ask yourself whether the extra electricity you use when your current unit cycles longer on a few hot days is greater than the expense of installing a new larger unit and the extra cost of running the larger unit every hour of every other day. Larger unit = larger blower motor, larger compressor = more $ per hour to operate every day.

Newer homes, in general, are better insulated and tighter built than older homes, which allows a smaller unit to handle the A/C chores. If the smaller unit needs to run longer on hot days, and if you only have an average of a dozen hot days per year, you will be money ahead keeping your current unit. Now, if I were living in SW Houston, where it never gets cool except during tornado season , I'd consider the larger unit.