-: HVAC, or the heating, ventilation,
and air conditioning system is really important
to our facilities, especially those containing
sensitive computer equipment and servers.
Computers and servers tend to release a lot of heat
during their operations, and that heat has to be dissipated
or it can shut down the server or cause it to overheat.
Now, to solve this problem, servers and computers rely
on their own system fans to draw in cool air
over that motherboard and exhaust out hot air
out into the room.
Over time, though, the room will become
hotter and hotter and hotter if we didn't have
a good HVAC system to cool it down.
Now, to best circulate the air around the server room,
you should design it with hot and cold aisles.
This allows all of the front of the server racks
to be facing each other, making designated cold aisles
where you'll be working,
while expending all of their heat out the rear
of their cabinets to what we call
the designated hot aisle.
Now, by focusing on the hot and cold aisles,
this allows us to set up better ventilation systems,
using our raised floors in a server room,
and dissipating that heat much more effectively.
Now, another use of an HVAC system is to maintain
the right humidity level in that server room.
After all, if there's too little humidity,
static electricity can build up
and cause electrostatic discharge
that can damage your components,
just as you learned back in your A+ studies.
Now, if you have humidity that's too high,
condensation can occur when that cold air
touches those hot servers,
and this can cause corrosion of the components
and damage to them, as well.
To get the best humidity settings though,
what you want to look for is an HVAC system
that attempts to keep the humidity
at sound 40% at all times.
That's not too high and it's not too low.
Now, many HVAC systems are also connected
to your organization's ICS, or industrial control systems,
or your SCADA systems, your supervisory control
and data acquisition systems.
This is a specialized network that's going to control
all of your manufacturing and facility systems.
This allows a remote operator to maintain awareness
of the humidity and temperature
in various parts of the building,
and insure that the HVAC
is functioning properly at all times.
Because your HVAC needs power to run
and be able to dissipate all that heat in the server room,
you need to be aware that if a power outage occurs,
this can cause a loss of your HVAC.
Now, if you lose your HVAC, you need to think about
what servers do you need to remain up
and which ones would you shut down
to try to minimize the amount of heat
that's being produced, until you can get
your air conditioning back online
and working once more.