I have been in the service industry most of by life before I got into servicing heating and air conditioning I worked on electrical and electronic equipment as well as doing my own auto repairs. In that time I have seen many myths and bogus information about how things work and common problems that are not. Once you understand how something works it is hard to reach anything but a correct diagnosis but wonders will never cease.
My all time favorite is the red-neck
tale that if you take an automotive battery (boat batteries too, especially
since they will be out of service for 6 months or more) and set them on
the ground then mysteriously the electrons will find their way through
the plastic case and disappear into the ground. The only problem with this
theory is the last time I checked plastic was an insulator and electricity
needed a path to follow. I have noticed that this theory is confined to
what I call the "Budweiser University of Auto Mechanics". My theory is
that the way this came about is "Joe six-pack" removed the dead battery
from the family car or pick up truck and the next day when he found it
on the ground it was dead. Think about it if that battery was any good
it would still be in the vehicle. That is why you see batteries stored
on wood in these situations. I have also heard the theory that the ground
will "cool" the battery. The only problem with this argument is what happens
in the winter time when it is -10 out.
So here starts my soon to be long list of stuff I find in the hvac trade.
Certain contractors play on the customer's ignorance and will sell a new thermostat as the first step to solving any problem and if the unit or any piece of the equipment is replaced so is the thermostat. I have been told by other contractors and in trade school that "the customer is so stupid that you must replace the thermostat or they will not know that they got a new unit". This is why most mechanics and contractors get such a bad reputation. Myself I usually replace one or two thermostats a year and that would be because they are damaged.
However those fine pleated paper filters that cost from $3 to $15 each catch everything and can clog up every month to the point where you have to change them constantly. The ones that claim to last 3 months I don't believe because there isn't enough media in a 1 inch filter to catch all the crap that passes through it in 1 month. I would suggest that if you want a filter that you can leave for 6 months at a time or even a year and catches everything look into the Trion Air Bear or the General Space Guard. This filter is 5 inches thick and can last a long time. I have installed several here in Maryland.
As for your equipment working harder. Except for a heat pump running in the heating mode where restricting the air flow will raise the head pressure on the unit causing it to actually "work harder" there is more to this. On a gas or oil furnace if you slightly restrict the air flow you will not cause it to burn more gas in fact on most gas furnaces the blower is slowed down to its lowest speed in heat mode, go figure. I am not saying restrict (that is another story) the air flow but it won't kill it to have a little bit of dirt on the filter. For air conditioning you need to have enough air flow to keep the coil from freezing and maintain efficiency but if you didn't if would actually make the compressor work easier (hard to believe). For electric heat it really doesn't care how fast the air flows it is still 100% costly. As for the indoor blower fan unless you totally stop the air flow the the motor can't get any ventilation it will actually work easier not harder if the air is restricted (see definitions below). The fan on your outdoor equipment is just the opposite. Also see the new LIST OF PHRASES. Truth be know that the most efficient units load up the compressor by employing larger coils.
Along those lines in addition to the myth
of the refrigerant going bad there are sales pitches that you must replace
your air conditioner or heat pump on a regular basis. If you are living
in a well to do neighborhood expect a contractor to condemn your unit even
if it is only 5 years old, the contractor will also have a quote ready
too (I have seen it happen when the unit just needed a defrost
thermostat). In not so well areas the units seem to last longer like 25
to 30 years but tend to need more service including freon. Do we see a
pattern here. Also see the new LIST
My latest pet Peeve is the belief that
the company who installed the system must be the best one to repair it
or that the last person to work on it should be the next in line. The truth
is that if the original contractor was lousy then , they are lousy now.
If they were great then, they are great now.
More to be added later
Good luck Scott Meenen n3sjh
This text written by: Scott Meenen * G & S Mechanical
Written By: Scott Meenen N3SJH of:
G&S MECHANICAL SERVICES.
Specializing in Mechanical, Controls and Electrical Modifications Of
Heating, Air-conditioning, Refrigeration, Cold storage,
Ice Production and Food preservation.
Anything having to do with Heat and Energy.
Serving Maryland, DC, and Northern VA.
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