I have a Bryant AC/Furnace unit. My house is 10 years old. A heat wave hit this weekend & temps got up to 95°F outside. I had my thermostat set to 75°, and it ran all day. The thermostat never dropped below 80° during the day & eventually cooled down towards the evening. How can I tell if it's a problem with my AC or with the insulation in the house? The attic has insulation "blown" in it, and from what I can tell, was done recently before we bought the house 5 years ago. Does the "blown" insulation have to be re-blown every so often? Or is it more likely a problem with the AC unit? I've never had it serviced since I bought the house, but I have changed the air filters monthly. Something else I remembered: my house is bi-level. I keep the downstairs vents closed because if they're all open, it gets pretty cold down there. With them closed, it's maybe a little warmer than upstairs. We're upstairs most of the time anyway. Would that affect anything? Your question almost exactly sums up the situation I had at my home last August.

What I found then was that despite a properly sized air conditioning unit and what I believe to be good insulation (the house holds heat well during the winter), the unit still couldn't keep up.why use an air handling unit I don't have full proof, but I think a few factors caused my situation and might be worth checking for you:ac wall unit not working The condenser (outdoor unit) sits in an "inside corner" with the house on two sides of it and a chimney and small storage shed that partially blocks a third side of it. what air conditioning unit should i buyThis prevents good airflow across the unit. [I can't do anything about this without relocating the unit, which is not a DIY job for me.] We had very little wind at all during the heat wave, which also added to the lack of airflow across the condenser.

The condenser was visibly dirty, which makes heat transfer to the outdoor air less efficient. Lots of dirt, dust, pollen, grass clippings, etc. build up on the fins over time. Normally rain will clean it off somewhat, but we hadn't had rain in ages. Despite some advice I've seen not to do it, I used a garden hose to wash off the fins of the condenser (it gets wet from rain, right?) very gently, taking care not to make it full of mud or to bend the fins. I could see water evaporating immediately on contact, and I have an infrared thermometer I used that showed a 30F or so drop in temperature in short order. The AC performed much better after that, but we also started to get a gentle breeze that helped things along. The easy answer is because your thermostat is telling it to run all day. So, should it or should it not be? Is the thermostat in a good position in the house? If it's directly in the path of a sunbeam, then it will get hot and run more than necessary to cool the rest of the the house down.

Is there enough cool air coming out each of the vents? If you close most of the vents, do the remaining ones have a stronger air force? If not, you might be leaking some air out of the ducts. If your A/C unit is 10 years old and has not been serviced in at least the past 5 years, it's probably worth the money for an inspection/service. This shouldn't be terribly expensive and is a good starting point. Monthly air filter changes also sounds like a little excessive to me. Also: Check for a second air filter if it's an older system. I was surprised to find a second one in my unit and promptly changed it. Another likely problem is that your system needs the coolant recharged. If the coolant is low, there is not enough to cool the air as it passes through the coil. You may have a leak somewhere, but the house is cooling somewhat, so the system is not empty. Regardless, call a qualified A/C person to service the unit.Browse other questions tagged insulation hvac air-conditioning or ask your own question.

It’s starting to get warm out there again as Spring is in full-effect and Summer is going to be coming quick. If you’re anything like me, then you know how uncomfortable it can be when you’re hot in your own home. I hate being hot, so I love air conditioning. I consider it one of the greatest inventions around, just due to how much I hate being hot. As someone who is relatively frugal, I’m always torn between blasting the AC on high and enjoying those frosty temperatures or saving money. Typically, I push toward saving money. The good thing is you can save money and use your AC if you just plan a little and use some technology. The majority of homeowners likely wonder whether it is better to turn off the AC while away or keeping it on all day. We certainly want to stretch every dollar, and we want the most efficient way of running things. But you also probably don’t want to die during the blistering heat of summer − which begs the question if turning the system off is worth the agony.

But some people believe that leaving an air conditioner at all times − even while away − is the better path towards smaller energy bills. I was lucky enough to have a HVAC technician help answer this question for me. Jason is a long-time HVAC tech who understands how air conditioners work and the answer to this constant question: “Should I turn off my AC while I’m away to save money?” Jason is going to take it from here! Being an HVAC technician for about 23 years, I’ve learned a good deal of how air conditioners work and how to maximize your indoor climate control efficiency. So, what about the belief that you shouldn’t turn off your air conditioner while away? The myth: Leaving your air conditioner on all day will help save money in the long run by not having to kick start it each and every time you turn it back on. By keeping your air conditioner on at all times during the day, you’re not using an air conditioner efficiently, because leaving the air on all day (even when you’re not home) results in a higher use of energy.

It would seem to be common sense that something that works harder is spending more energy, but this assumption is not an accurate reflection of how air conditioners work.  Fluctuating to accommodate for a constant temperature is far more taxing on an air conditioner than when it’s working at full capacity. Air conditioners work best when they are operating in full gear. Leaving the air conditioner on throughout the day is also more damaging to your system. You’ll see several years added to the life of your system if you use it only when necessary instead of relying on the superstition that constantly running a system is somehow beneficial. Cut this habit now, and you’ll also notice a difference in your utility bills in no time. Most people don’t realize that by altering the temperature on the thermostat by one degree, your air conditioner is working at a difference of 5% — resulting in you saving or wasting your money in the long run. Pick the temperature that is right for you and your family.