Is it me or my AC? (home, buy, contractors)

[tstone]

Originally Posted by Wysiwyg

an AC guy posted here a while ago and he did say the same thing. minus 20degrees max. i do mist my AC unit to cheat hehe
but 2 days to bring it down to 80? that may need a fresh shot of refrigerant

This 20 degree differential is what I was told also. When it's the usual 95-96 outside, you can't expect it to cool to less than 75-76. And that's with the proper tonnage/BTU rating + running it all the time. This is where thermostat settings of 78-79, ceiling fans, and a little acclimation can work wonders for the electric bill.

Sbhubbell, you really need two independent units for that size house. For example, a 4 ton unit for 2,000 sq ft downstairs + 3 ton unit for the 1,600 ft upstairs. If you don't have 2 units, you might have found the reason why the house was sold off.

BTW I misted my AC as well but wound up with rusty filter screens.....

[Wysiwyg]

Originally Posted by tstone

BTW I misted my AC as well but wound up with rusty filter screens.....

dude. maybe you got the 'interior' type AC unit

[tstone]

Originally Posted by Wysiwyg

dude. maybe you got the 'interior' type AC unit

I just pointed some mist up into the larger of the two filters. That white, metal grille got a little rusty a week afterwards. Oops. I can probably sand it off & prime when I get some time, though.

[EasilyAmused]

Doesn't sound right. I can get my leaky old 1967 (3900 sf) house down to 68 on my zoned system.
Might have freon leak.

Of course I have ton of huge old trees that shade the house. That may be helping.

[Va-Cat]

Originally Posted by sbhubbell

Ok y'all, is it normal for a two-year old AC system (zoned) to have trouble cooling a 3600 sq ft house during the day? We have it set to 74 and it can't get to that until late at night. The previous owners had it set to 81 and it took two days to even get below 80. I realize it's super hot outside but I never had this problem when it was hot at my old house in Philly and there I only had one unit for the whole house. The filters were pretty filthy so my husband changed them.

Look into having a solar powered attic fan installed. We had one in our house in Florida and it seemed that the A/C unit didn't have to work as hard and cooled the house a lot faster. It turns itself on when the attic temperture reached a certain point. Also dropped our A/C bill by about $50.00 a month. All installed, I think it cost us somewhere around $450.00. We are going to have one installed here too.

[cla]

I'm betting that your home in Philly didn't have the expansive open floor plan that your new home has. It is amazing just how much large, open spaces are harder to keep cool than small, enclosed spaces, especially without mature shade trees to help. Back in N.O. I would normally keep my thermostat at 78 which was comfortable, but the 40 year old house was divided up as was typical back in the day, additionally, I had tall trees which helped shade the house. Here, I have to put it down to 73 to have that same level of comfort, and still the large open areas aren't nearly as cool as the bedrooms. And I'm only cooling 2100 sf. I did see an improvement, however, when I had the builder replace the thermostat - it didn't seem to be working as well as it originally did (not getting down to the temperature I set it at). Once it was replaced, all was well (knock on wood).

Personally, I think I could use another duct or two, but the builder insisted that the ducts were adequately sized for the house. I know better - I can't turn the heater on in the winter without turning my daughter's bedroom into an oven - even with the vents closed (she's a teenager and insists on keeping her bedroom door closed).

Additionally, if they had a home warranty, I am sure they called in about the same problem (unless it broke down between the time they moved out and you moved in).

[EasilyAmused]

Agreed. If you have two story ceilings, or a "balconey" that opens from the second floor into the first,you'll never get the upstairs AC to much lower than 74 or 75. That unit will run 24/7.

[sbhubbell]

Yes, we do have the huge open floor plan with the two story ceilings, and yes we get a lot of direct sunlight, although we keep the blinds down and have solar screens in upper windows. The unit is 2 years old, as is the house. No trees of course, but we got tons of direct light and had no trees in Philly too. I do have two completely separate units, the upstairs one seems to be working a little better than the downstairs...our master bedroom being the warmest in the house, and the downstairs thermostat is inside our bedroom doorway. The ceiling fans do help a lot, but the temps just seem to be imbalanced, and I'm sure it must be running all day long at this point which has got to be murder on our power bill. I'd probably be ok setting it a bit higher but I'm just worried there may be something actually wrong (like a freon lead or something) and I probably will get it checked while it's under warranty.

I can guarantee you the previous owners never complained about it or called on it...they balked when our inspector said their might be a problem, and we can tell that nothing in this house had been maintained at all in the two years since it was built. The previous owners are unbelievable...they STILL haven't called to disconnect the phone, power, or forward the mail. We are fighting with utility companies to make the switch.

[Wysiwyg]

Originally Posted by tstone

I just pointed some mist up into the larger of the two filters. That white, metal grille got a little rusty a week afterwards. Oops. I can probably sand it off & prime when I get some time, though.

not sure whats going on there. everything is wet outside every morning from the dew so they should be built to get wet. what is this filter you are refering to? I only run the mister on real hot days so its not that frequent. the condenser is made of aluminum and then theres some screen there that is made of plastic so i'm wondering whats up with yours

[Wysiwyg]

I had a cooling issue with one room too. the bigger bedroon upstairs cool down the slowest. when I was installing recess lighting I investigated and found out that the flex ducting had a kink. I rerouted that and cooling the room got alot better. I also shut of cooling from 1/3 ducting in the game room and shut off cooling in the toilets/showers where theres a fart fan - this then distributed more to bedrooms.
i suggest you check how cool is the air coming from the ducting and if you have considerably even flow from them. you also might have a fan on/auto switch on your thermostat - i find it better to set it at auto.
another thing i noticed about my AC system... my house would not cool down (AC on standby) if the temp outside is about the same as my temp setting inside weird i have to set it a few degrees lower to have it cranking in order to reach our comfy temps. I have one of those clocks with outside temp sensor so I can check if this is the case