When the weather gets hot we rely on the Air Conditioning in
our units with cabs on them to help keep us cool. These systems work great, but there is some maintenance
to them as well. When it is hot, you
blow out your radiator to keep your engine cool, but sitting on top of that cab
is a different kind of radiator that needs to be serviced to keep you cool.
It helps to understand how the AC system works to know
exactly how service affects its performance.
No matter where the AC system located, in a house, a car, or in a Toro mower, the
basics of the system are the same. There
are three main components to the system.
Compressor –
Spun by the engine and charges the system
Evaporator coil
– This is the coil that gets cold and we force air over it to cool the air in
the cab. It is located above the
headliner within the cab.
Condenser coil –
This is the coil that gets hot and we force outside air over it to cool
it. Just like a radiator for the
engine. It is located on top of the cab
and has a fan mounted on it.
You may have heard about high and low limit switches on an
AC system. The low switch turns the system
off if the pressure gets too low. (If
there is a leak) The high pressure switch shuts the system off if the pressure
gets too high. This happens when can’t cool
down the condenser coil because we cannot get enough air across the coil. (Typically
because it is plugged)
 |
| AC Compressor |
The top things I see affecting AC performance on our units
are a compressor belt not being tight enough, or a plugged condenser coil tripping the high pressure switch. A plugged coil can put stress on the entire
system causing other failures as well.
Pump seals, hose fittings, and coil leaks can all result from a plugged
condenser coil.
 |
| Pull out screen under coil |
There is a screen located beneath the coil to help keep the
coil from plugging up, but it needs to be serviced regularly. Just like the engine radiator, how often it
needs to be cleaned depends on the conditions.
If you have to blow out your radiator more often, your AC condenser will
also need to be cleaned. Just cleaning
the screen may not be enough at times.
You may have to pull the fan and shroud to gain access to the coil. With this removed, you can properly clean the
coil with compressed air and or water.
Keeping the condenser coil clean will help keep stress off
the system and keep you cool when you need it most.
