[JaydeeCan]

Hello gentlemen and thanks in advance for any assistance/advice.

I had an new Goodman GME95 40,000 BTU furnace and a Goodman GSX16 1.5 ton air conditioner installed yesterday.
Single story house ~850 sq. ft. main floor and another 850 sq. ft. basement with adequate insulation and 15 year old windows but still fairly tight I'd say.

Last night it took 4-5 hours for it to cool the house from 27 (80.6 F) Celsius to 23 (73.4 F).
I told this to the installer when they came by today to install a new hot water heater and he told me it was his initial setup and that he would fine tune it today.
Okay I can accept that.
Well he did his fine tuning this morning and told me the coolant pressure was too high and he adjusted that and some other things.
Okay.

But it is still taking forever to bring the temps down in this small house.

I didn't give him the final payment (there was a 30% down payment required) until I figure this out as it is not the performance I expected.

I know you can't give definitive answers without seeing first hand but do these numbers seem out-of-whack?

 

[dakota62]

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[hearthman]

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[udarrell]

Well, is 27-Celsius to 23-Celsius around a 7.2°F drop in temp from say from 80.6°F down to 73.4°F?
If so, that could take some time, depending on a lot of presently unknown factors.

We need to know the humidity level within your home.
There could be a lot of moisture within your home that has to be removed, before the sensible ratio rises to a point where the temp comes down faster.

Take the indoor supply air & return air temp-split; then the outdoor condenser discharge air temp compared to the out door temp.

It could be a problem with your home; too much air infiltration & other problems...

There could be a problem with the duct system & airflow...also, whether the install as performed properly by the sequence numbers.

You can get a humidity gage at a hardware store at a very low price; every home needs one.

 

[JaydeeCan]

Thank you for the reply.

The outdoor temps were 25 to 27 degrees. Very high humidity.
I am from Toronto Ontario area.

It replaces a 1.5 ton Heil AC that worked fine for 15 of the last 18 years and has been limping along for the last 3 years.
When the Heil was working properly I don't recall it taking this long to cool the house.

 

[motoguy128]

How quickly do you expect it to cool off the home? Why do you expect that? Most peopel don't realize that long run times make units more effceint, make a home more comfortable and EXTEND equipment life. That's right. Its' the repeated stopping and starting of the equipemnt that wears it out. Thsi is called short cycling. The longer the better.

What was the temprature outside? It sounds about normal. When it's near desing condtions, it may take hours to cool the house down, but will easily maintain temperature. No reason a small home like that should need anything bigger than that. Be happy you have a unit that is sized correctly. It will make the home more comfortable with lower humidity, more even termpature and run more effceintly with long run times. Setbacks do not save money unless you start cooling the house down at 10PM (not practical unless you work 3rd shift).

Best to leave it the same temperature all day, then turn it down for comfort in the evening before bedtime if that's your preference.

In my house, if it was 80F indoors, it would take probably 8+ hours to cool it down by 7F on a hot day.

If you for example had a 2.5 ton uni in ther eto cool it off in just 1 hour, the rest of hte time it would run only 50% or less on hot days, and you humidity indoors would be higher and it would use as much as 30% more energy because you have ot set it cooler to reach the same comfort level.

 

[motoguy128]

Thank you for the reply.

The outdoor temps were 25 to 27 degrees. Very high humidity.
I am from Toronto Ontario area.

It replaces a 1.5 ton Heil AC that worked fine for 15 of the last 18 years and has been limping along for the last 3 years.
When the Heil was working properly I don't recall it taking this long to cool the house.

Heck, in that case, I think those temps are almost design conditions, and a 1.5 ton is stil probably a little oversized there. Remember, when you change the temp of a home, in addition to offsetting the heat gain form outdoors and indoor heat loads (lights, appliances, people) you are cooling of the air itself, walls, floors, furnishings, etc. That could be several thousands lbs of material. When you are maintaining temperature, you are just removing hte heat that a house gains from the outside and indoor heat loads.

Ever notice that a car get terrible mileage in winter compared ot summer. Part of that is the very cold air and lower operating temps making the engine operate less effceintly. But much of that, especailly if you drive short trips, is the energy needed just to warm up the engine block,transmission, oil, fluids. That could be 1000# of material. That takes a lot of energy, and until a engien is warmed up, some of that energy comes is "stolen" from making horsepower. So you need more fuel to make the same power.

For example, I moved into my new house and have a heated garage. My daily fuel economy instantly increased by 20% in the same conditions, despite my very, very short 2 mile commute getting even shorter. I'd get down to 13mpg in the middle of winter, but in mild weather 20mpg, then back down to 17mpg in summer when I'm using AC.

 

[JaydeeCan]

Thanks for the replies!

Hmmm... OK so "Turtle and the Hare" where slow and steady wins the race as far as power consumption goes.

As for what I expected... from past experience I expected it to take less than half that amount of time to bring the temps down 4 Centigrade = so 1-1.5 hours. After all this is a very small house.

I wasn't saying that I thought 1.5 ton wasn't enough because as I said it replaced a 1.5 ton Heil that worked great for 15 years.

I was more concerned if the slow cooling rate could indicate problems with the installation or equipment.

While the new furnace and AC were being installed I had a dehumidifier and a 5000 BTU portable AC going to keep things tolerable inside.
When the install was completed the temp outside and inside was 27 Centigrade and fell to 25 C outside by 10 pm and the new AC managed to get the indoor temps to 23 C by 10 pm.

Thanks for the replies!