Think You Know Air Handlers?

swcoil_superadminAir Handlers

Take Southwest Coil’s “quick quiz” and test your air handler knowledge.

Match the lettered terms on the left with the numbered meanings on the right. This is fun, and you may learn some useful information about normal air handler terminology.

NO PEEKING – Answers Below

QUESTIONS:

A. ESP
B. RPM
C. SCFM
D. Fluid BTUH
E. APD
F. MERV
G. Outlet velocity
H. Safe-offs
I. Rail
J. Water removal
K. Double
L. Economizer
M. Fluid velocity
N. Two circuit
O. VFD qualified
P. Bottom water inlet
Q. Upstream heating coil
R. Upblast
S. BHP
T. Typical light
1. Around coils
2. Drain pans
3. Intertwined
4. Fan
5. Chilled water coil
6. Out the top
7. Operating speed
8. Actual power rating
9. Air load equal
10. In coil tubes
11. Uses fresh air
12. Standard volume
13. Circuit
14. Resistance
15. Preheat
16. Pressure outside of unit
17. Mounting
18. Motor
19. Rating
20. Marine

Tip of the day

It’s important to know that Southwest Coil manufactures direct drive fan coil units, single wall belt drive air handlers, and indoor and outdoor double wall central station units. Our primary markets have always been in replacement, retrofit and fast shipment projects – for over 5 decades. These 3 markets require Southwest Coil’s engineered knowledge of existing designs and arrangements. We are also able to assist you with problem systems that need changes or upgrades to improve their overall efficiency. For professional, knowledgeable assistance, contact us at [email protected] or 610.580.3004.

Historical Quote:

“All throughout nature, you will find the same law. First the need, then the means.”

ANSWERS:

A. #16 – Pressure outside of unit – External static pressure (ESP) is a term used to establish all resistance in ductwork, grilles, registers, dampers, etc. outside of the unit.
B. #7 – Operating speed – usually of a fan in an air handler
C. #12 – Standard volume – normally the amount of air at standard conditions
D. #9 – Air load equal – Example: cooling – whatever heat is taken out of the air allows you to calculate the same BTUH being placed into the water.
E. #14 – Resistance – is what air pressure drop (APD) is all about
F. #19 – Rating – The filter industry rates filter efficiency with an easier numbering system.
G. #4 – Fan – a fan has an outlet size and when a defined flow of air passes through it, it’s considered to be the outlet velocity of a fan.
H. #1 – Around coils – Safe-offs are normally used around coils in an air handler to be sure the air goes through – not around – the mounted coils.
I. #17 – Mounting – rails are used on bottom or top of air handlers to mount units to pads on the ground or to suspend from ceiling.
J. #2 – Drain pans – removes water in air handlers – drain pans must be a calculated distance downstream of the coil to catch all moisture being dehumidified.
K. #13 – Circuit – is what closely matches up with double. A double circuit coil is a coil term used to pinpoint that all the tubes in two rows of coils are fed by the manifold leading into the tubes on a coil.
L #11 – Uses fresh air – Economizer uses fresh air when the temperature falls to the return air design temperature. No one wants the cost of using fresh air and that’s eliminated when fresh air and return air are the same.
M. #10 – In coil tubes – Fluid velocity is a measurement (usually in feet per second) inside a coil in an air handler that deals with overall BTUH of coil and water pressure drop
N. #3 – Intertwined – is the name of a two-circuit direct expansion refrigerant evaporator coil. Basically, intertwined means that every other tube in a coil is part of one circuit, and all the other tubes are a part of the other circuit.
O. # 18 – Motor – must be qualified for use with a variable frequency drive (VFD)
P. #5 – Chilled water coil – normally has a bottom inlet and a top outlet. The water is pushed from the bottom to the top, so the air bleed works more efficiently.
Q. #15 – Preheat – a preheat coil is always upstream of the cooling coil, so that air hits the heating coil before it hits the cooling coil.
R. #6 – Out the top – when a fan is upblast, its discharge direction is out the top
S. #8 – Actual power rating – of a fan at operating conditions is known as brake – horsepower (BHP).
T. #20 – Marine – light is normally used for lighting up areas inside an air handler. A marine light deals with moisture that can be prevalent inside any section in a unit.

If you scored:

10-15 – very good
15-17 – excellent
18-20 – air handler genius