AIR CONDITIONING
With the time of year being what it is, it seems like an ideal time to talk a bit about air conditioning systems. Your A/C system is like your garbage disposal in that it will pick the worst possible time to malfunction, like Thanksgiving afternoon. And if you are used to having it around and in working order it becomes a major inconvenience when it suddenly becomes unable to perform.
There are several different styles of air conditioners, from the simple single room type and the “thru-wall” style that are meant for small homes or to condition part of the home, to the central split system style which is part of a full central ducted heating and cooling system. They all work on the same principal. Let’s look at a split system. A refrigerant is circulated inside a copper line, and is fed into a compressor. The compressor usually sits by itself in the back yard and has a big fan that blows when the A/C is on, it’s about the size of a large doghouse but taller. The compressor compresses the refrigerant (which is a gas at this point) and squeezes it into a liquid. Heat is generated during this compression and that heat is drawn off and discarded (by that fan). The compressed refrigerant is then transported inside its copper line to the main HVAC unit, probably inside your house or garage. The super cold liquid refrigerant is run thru a coil of tubing with air blowing over it, allowed to expand and turn back into a gas. As the refrigerant expands it recaptures most of the heat from the air that was taken from it when it was compressed. And it is recapturing it from the very air that will be blowing into your home in a few more seconds. That’s how air conditioning works. You can, with some minor changes, reverse the process and you’ll have a heater. You’ve seen this type of heater/ air conditioner on motels everywhere, they’re called heat pumps.
SEERS & EERS
The effectiveness or efficiency of an air conditioner is measured in a couple of ways. For many years the standard has been the SEER. This is the Seasonal Energy Efficiency Ratio, but more recently the EER (just plain Energy Efficiency Ratio) has started to gain in popularity. The EER is supposedly the more accurate of the two and is the preferred designation moving into the future. For now we still use SEER, and a minimum of 13 SEER is what is required for a new A/C installed today. Some of our older housing stock in the 30 & 35 year old range have air conditioners that have reached the end of their useful life. These older A/C’s are average 8 SEER units. They also use an old style refrigerant called RA22 that has been found to damage the earth’s ozone layer and therefore has been banned. All newer equipment has the newer R410A refrigerant.
While a 13 SEER is certainly much more efficient than an 8 SEER unit, 13 is just a minimum. There are air conditioners that go up over 19 SEER. These units are real trick. Like their partners in the furnace world, they have a two stage cooling capability by utilizing two compressors, and they have a variable speed fan. So when your home is cooled to temperature, only the single smaller compressor needs to come on and the fan only needs to blow at a slow speed to keep the home cool. You’ll hardly hear or feel anything. These units are usually set to come on with no heat or cool every so often just to stir the air to keep it fresh. The new HVAC systems have come a long way, and it’s going to be needed. As soon as everyone has a smart meter, if we should have to go to “time-of-use” billing, those people that still have those 8 SEER A/C units may find they can’t afford to run them.
Something else I’ve heard is that solar Photo Voltaic systems are finally coming down in price enough that with the tax credits and rebates it starts to make sense to look at being able to run your A/C all summer for only the cost of the solar investment. Summer months of no A/C electrical bills, might be worth looking into.
One thing that can hurt the performance of your air conditioner as well as your furnace, no matter how new or how efficient, is a dirty filter. Check them every couple of months and more often if you find them dirty. For the small price of a filter it’s well worth having a clean one in the system at all times.
With the time of year being what it is, it seems like an ideal time to talk a bit about air conditioning systems. Your A/C system is like your garbage disposal in that it will pick the worst possible time to malfunction, like Thanksgiving afternoon. And if you are used to having it around and in working order it becomes a major inconvenience when it suddenly becomes unable to perform.
There are several different styles of air conditioners, from the simple single room type and the “thru-wall” style that are meant for small homes or to condition part of the home, to the central split system style which is part of a full central ducted heating and cooling system. They all work on the same principal. Let’s look at a split system. A refrigerant is circulated inside a copper line, and is fed into a compressor. The compressor usually sits by itself in the back yard and has a big fan that blows when the A/C is on, it’s about the size of a large doghouse but taller. The compressor compresses the refrigerant (which is a gas at this point) and squeezes it into a liquid. Heat is generated during this compression and that heat is drawn off and discarded (by that fan). The compressed refrigerant is then transported inside its copper line to the main HVAC unit, probably inside your house or garage. The super cold liquid refrigerant is run thru a coil of tubing with air blowing over it, allowed to expand and turn back into a gas. As the refrigerant expands it recaptures most of the heat from the air that was taken from it when it was compressed. And it is recapturing it from the very air that will be blowing into your home in a few more seconds. That’s how air conditioning works. You can, with some minor changes, reverse the process and you’ll have a heater. You’ve seen this type of heater/ air conditioner on motels everywhere, they’re called heat pumps.
SEERS & EERS
The effectiveness or efficiency of an air conditioner is measured in a couple of ways. For many years the standard has been the SEER. This is the Seasonal Energy Efficiency Ratio, but more recently the EER (just plain Energy Efficiency Ratio) has started to gain in popularity. The EER is supposedly the more accurate of the two and is the preferred designation moving into the future. For now we still use SEER, and a minimum of 13 SEER is what is required for a new A/C installed today. Some of our older housing stock in the 30 & 35 year old range have air conditioners that have reached the end of their useful life. These older A/C’s are average 8 SEER units. They also use an old style refrigerant called RA22 that has been found to damage the earth’s ozone layer and therefore has been banned. All newer equipment has the newer R410A refrigerant.
While a 13 SEER is certainly much more efficient than an 8 SEER unit, 13 is just a minimum. There are air conditioners that go up over 19 SEER. These units are real trick. Like their partners in the furnace world, they have a two stage cooling capability by utilizing two compressors, and they have a variable speed fan. So when your home is cooled to temperature, only the single smaller compressor needs to come on and the fan only needs to blow at a slow speed to keep the home cool. You’ll hardly hear or feel anything. These units are usually set to come on with no heat or cool every so often just to stir the air to keep it fresh. The new HVAC systems have come a long way, and it’s going to be needed. As soon as everyone has a smart meter, if we should have to go to “time-of-use” billing, those people that still have those 8 SEER A/C units may find they can’t afford to run them.
Something else I’ve heard is that solar Photo Voltaic systems are finally coming down in price enough that with the tax credits and rebates it starts to make sense to look at being able to run your A/C all summer for only the cost of the solar investment. Summer months of no A/C electrical bills, might be worth looking into.
One thing that can hurt the performance of your air conditioner as well as your furnace, no matter how new or how efficient, is a dirty filter. Check them every couple of months and more often if you find them dirty. For the small price of a filter it’s well worth having a clean one in the system at all times.
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