Guess that it depends on what part of the country you are in. I live in central NC and use the heat about as much as the AC. Very few days over
100 and lower 25 deg F. The heat or AC of th eheat pump is used almost every day of the year. One about as much as the other.I think our house was bult with just the easy way out. The down stairs has vents at the floor level, but the 2 upstairs bedrooms and bath have them in the ceiling. The return is located about halfway up the stairs.
That is obviously all you can do. My one inch filters are 1X16X20". I change every 4 months unless there is a long spell with no need for heat and AC. Filter may not appear to be very dirty but a little sediment could reduce through put considerably.
A dirty filter:
1) Reduces the airflow available to the heat exchanger. This could result in the high-limit switch opening, which will increase the cycle time (and blow colder air util the high-limit switch closes after the heat exchanger cools sufficiently, rinse and repeat). 2) Causes the blower to work harder, which consumes additional power and prematurely ages the blower.Right. Replace filters when they get dirty.
A filter can clog fast without appearing that dirty. Happened to me with my well problem where the whole house water filter clogged after only 2 days with new pump.
I change my furnace filters every 3 months unless there is extended non use of heat or AC.
I wonder why the refrigerator companies haven't designed in a filter? Same problem here, the coils are tucked underneath, you can't get to anything more than the front of it to try to clean it. Not only would it be of benefit to us, but it would be another revenue source for the companies, selling the replacement filters. These suck in air at the worst place, right at the floor surface where they pull in dust, pet hair, etc and get dirty fast.
Very good advice. Most people think you should just change them when dirty. Saw the same thing with a water filter with my well problem. The new pump stuck in the well clogged the filter in a couple of days. It hardly looked dirty but fine pores were clogged and water flow slowed to a trickle.
In reality you don’t get an accumulation of muck around the fridge compressor, essentially because air isnt blown over the exposed coils at the back of the fridge or freezer, they are cooled by convection.
You don’t get an accumulation of muck even with frost free fridges and freezers which blow the cold air thru the inside of the fridge or freezer.
The most you get with my fridge in very humid weather is a bit of a burble when you close the door due to the feed of the water that is condensed out of the air before the air is moved into the body of the fridge being under the water surface in the bowl on top of the compressor where it evaporates due to the compressor waste heat.
Compressor? It's the condenser coils fool.
essentially because air isnt blown over the exposed coils
Maybe on your old hillbilly fridge. On my modern fridge, like the other poster has too, the condenser coils are underneath and they use a fan to draw air over it. Even basic cheap fridges and freezers don't have exposed coils in the back anymore. That's so 60s.
The cold air path isn't the issue, fool. It's the ambient air being drawn over the condenser coils.
Burbles? Must have missed your meds again.
I thought we were discussing furnace filters. What does an air compressor have to do with it?
The facts are that the air handler in the furnace needs to work _harder_ when the filter gets dirty. Working _harder_ requires more current.
It would seem to me there are two competing factors. Clare says that a fan with a dirty filter moves less air, so that means less current. That certainly would be true, all things being equal. You raise a good point though, that it's not necessarily just about how much air is moved, but the force required to pull what air it's moving. If I'm lifting 30
1 lb balls a minute off the floor, it takes X power. If I'm lifting only 20 1 lb balls a minute, it takes a third less power, 0.66X. But if I'm lifting 20 1 lb balls and they are being held back now with a small spring, representing a dirty filter, then the power used will be more than .66X. I think in the real world, for an ordinary blower motor, with a restricted filter it does wind up using less power with a clogged filter. Ultimately if you clog if enough, the blower winds up cavitating and the power drops even more. The new ECM, variable speed blowers though, I think behave differently and may use more power with a clogged filter.
No - you are wrong. The squirrel cage blower of a furnace IS an "air compressor" - and not a positive displacement one. Power consumption is rependant and the mass of air moved, and a furnace blower draws LESS current with a blocked filter. It draws more current per cu ft (or lb) of air moved, but the decrease in air moved is much larger than the "efficiency" in watts per cu ft, so the blower draws less current. The effect is less than in a "turbine" type blower - but it is VERY real.
here are some actual measurements gleaned from other sources:
Dirty filters drop the amps - Less airflow equals less amperage. Here ya go info on a squirrel cage Low speed filter quality amps none n/a 7.4 panel clean 7.05 pleated clean 6.75 pleated dirty 5.4
High speed none - n/a 13.10 panel - clean 12.92 pleat - clean 12.77 pleat - a bit dirty 12.70 pleat - dirty 12.30 pleat ~90%; blocked 12.20
Notice that on low speed with no filter the blower drew 7.4 amps, and with a dirty pleated filter that dropped to 5.4 - a drop of 2 amps - or 37%
On high speed the fan with no filter drew 13.1 amps and with a 90% blocked filter that dropped to 12.2 - a drop of .9 amps - 0r about
6.9%At high speed the percentage drop in air flow was less than at low speed - but still significant - and more significant - the current DROPPED in both cases with restricted filters.
That is true of cheap vacuums which are cooled by the exhaust air going through the motor, which is why tangential bypass motors are used in high quality vacuums. A tangential bypass motor actually cools BETTER when the airflow is restricted,(because the cooling fan is running faster and moving more air) while a flow through motor WILL overheat and burn out with a blocked hose or full bag.
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