Tech Talk With Lazydays Expert Mike Willet
RVIA/RVDA Master Certified Technician
35+ Years RV Experience
It’s summer, which means RVers everywhere are trying
to tame the gods of heat and humidity with the divine
invention of air conditioning. Here are a few tips
to keep your RV’s A/C system in shape through the
sweltering summer months.
How an Air Conditioner Works: The Simple Explanation
An air conditioner essentially sucks air through its intake and extracts heat
from it by running the air through an evaporator. The cold air that remains
is distributed through the vents and cools the interior of your coach.
The most important aspect of a well-running A/C system is airflow.
Maintaining proper airflow in your RV’s air conditioning system is crucial
to ensure that your unit runs as it should.
Filters
Keeping your interior filters clean is a great first step toward maintaining
airflow. You can replace your filters when they get dirty, or you can clean
your filters and save the expense of buying new ones.
To clean your interior A/C filter, remove the filter, wash it with water,
shake out the debris and reinstall it. A clean filter allows air to flow.
Roof Units
Your outside unit can accumulate dust, dirt and leaves that can inhibit
airflow. It’s always a good idea to keep the unit clean so air can fl ow
through it properly.
To clean your roof unit, you must first remove its housing. Then
take a hose and wash the condensing unit by running water over the
coils. The coils will dry naturally when you restart your A/C unit. There
is no need to use a spray nozzle or attack the coils with any kind of
pressurized water, since this can potentially collapse the fins and reduce
airflow. If you happen to collapse your unit’s fins, you can buy a fin comb
at most auto parts retailers and use the comb to brush the fins back to
their proper place.

Know When to Call a Pro
You got into the RVing lifestyle to have fun, not to deal with the
intricacies of malfunctioning air conditioning systems. (Leave that to
us technicians.) While it’s great to have a do-it-yourself attitude with
your RV, understand that the inner workings of your A/C system are
complicated and best repaired by a certified RV technician. Remember
that airflow is the most important aspect of a well-running A/C system.
If your coach is still uncomfortably warm after you’ve performed the
tasks we’ve discussed in this article, call a professional RV service center
and have your system checked out by a qualified technician.
Have fun and stay cool!
A Few Tips from Mike
What Is a Thermistor?
A thermistor is an electronic sensor
that reads air temperature and sends
a signal back to your A/C unit, letting
it know how hot or cold the interior of
your coach is. Your RV likely has several
of these devices placed around the
coach. Be aware that thermistors are
sometimes aesthetically located in odd
places, like inside cabinets or near light
fixtures, which can lead to inaccurate
temperature readings.
Running fans inside your coach is a
good idea. Fans promote airfl ow and
help thermistors achieve more accurate
readings, since fl owing air is easier to
gauge than dormant air.
Did You Know?
On average, a central A/C unit in an RV
can produce air that is 20-25 degrees
cooler than the temperature of the air
before the unit is turned on. So if it
is 90 degrees in the coach when you
turn the A/C unit on, your RV should
be able to produce air that is 65-70
degrees in temperature.
By comparison, the A/C unit in your
RV’s dashboard can produce air that
is 15-20 degrees colder than the
temperature of the air when the unit
is turned on.
Condensing Cleaner Caution
I recommend that you do NOT use
condensing cleaner on your A/C
unit, as it can corrode the clear coat
on your RV and ultimately damage
your coach’s paint. When certifi ed
technicians professionally clean
a condensing unit, they will use
condensing cleaner. However, they
will remove the entire unit from
the roof when they do this so the
condensing cleaner does not damage
the RV’s clear coat or paint.