AC Maintenance: When to Clean Your System

AC Maintenance: When to Clean Your System

AC Maintenance

When to clean?  When to clean?  Do you even need to clean it?  Well it has been something of a controversial subject for many years.  Personally we find the concept that it does not require cleaning to be ludicrous, ridiculous, brain dead and/or any other expression of something just being stupid on its face. AC Maintenance is extremely important.

Not since Ignaz Semmelweis, Hungarian-born physician began pushing physicians to wash their hands before delivering babies, has the idea been accepted that cleaning something is just unnecessary.  Dr. Semmelweis observed in 1847 that the death rate of women from childbed fever was significantly more frequent in women assisted by medical students than those by midwives.  He observed that medical students would often assist in birthing after performing autopsies on patients who had died of sepsis.  Dr. Semmelweis instituted a strict hygiene policy of hand washing with an antiseptic solution.  Deaths of women resulting from childbirth dropped dramatically.  Of course he received his “just rewards” from the scientific/medical establishment, because everyone knew it was “settled science” or “consensus science” that hygiene or washing hands had nothing to do with infection.  Dr. Semmelweis persisted and finally won the day, but began suffering from depression due to the continuous criticism.   In 1865 he was admitted to a mental hospital where he died two weeks later at the age of 47.  And wasn’t it Galileo who was imprisoned for disagreeing with the established science of the day?  They called it heresy.

As for me, I tend to agree with Michael Crichton, the mega-successful novelist, “There is no such thing as consensus science.  If it’s consensus, it isn’t science.  If it’s science, it isn’t consensus. Period.”

And this brings us sort of circuitously to AC maintenance and cleaning of HVAC (Heating, Ventilating and Air Conditioning) systems.  It could be I’m a bit behind the times, so maybe the powers that be are no longer playing the tune that HVAC systems do not require cleaning.  If you believe that, you should see some of the pictures of duct interiors before and after cleaning.  You wouldn’t want to breathe air that flows through some of those ducts.

Maybe it’s Hollywood that is causing the confusion.  Surely you have seen celluloid heroes escaping or hiding or being chased through ventilation ducts.  Those ducts are so clean you could eat your scrambled eggs off them.  The heroes come out of those ducts without so much as a smudge on the knee of their trousers.  Now juxtapose that picture with how workers look who have actually “crawled” larger ducts cleaning them by hand vacuuming.  I could tell you some stories – or show you some pictures.

Even with good filtration, there are often situations with filters not fitting snuggly so there is some air that bypasses the filters.  Some small particulate including bacteria and mold spores can actually pass through the filters unless they are HEPA (High Efficiency Particulate Arresting) filters.  Filters do break down and particulate can actually come loose from the filters and blow downstream.  After years of just this particulate, ducts can become quite dirty.  Evaporative coils become wet during cooling season.  Moisture with any organic particulate and mold spores is the combination needed for mold growth.  So not just particulate, but mold amplification can also be a problem.

Hopefully we have at least made you somewhat amenable to the idea that HVAC systems need to be cleaned every now and then and AC maintenance should occur once a year.

All right!  How do you know when to clean them?

1)        My rule of thumb is that the entire HVAC system should be cleaned ever five to eight years based on their environment and use.

2)       If you move into a house or building that has been previously occupied, you are inheriting the life style of the previous occupant.  This makes cleaning a prudent activity.

3)       If you have been in a house or building for few years and don’t remember if the HVAC systems have ever been cleaned.

4)       If you come into your office in the morning and regularly find gritty or fibrous dust on your desk.

5)       If you see black material caught in ventilation supply grills.

6)       If air handlers are replaced but installed using the existing ducts.  (More powerful airflow from the new unit is likely to dislodge and blow particles downstream into the occupied spaces.)

7)       If there is a lot of coughing and/or sneezing in your office area.

8)       If people complain of watery or itchy eyes.

9)       If you notice musty odors especially when the HVAC system first comes on.

10)    If you have product open to the air that could become contaminated.