T-Series Climate Changer ® Air Handlers Sizes 3 through ... - Trane

T-Series Outside Air Inlet Hood CFM
Limitations
Each T-Series unit has a rated nominal
cfm (a #3 for example is 1,500 cfm).
These nominal cfm’s allow for an
engineer to quickly base his unit size
requirements. Although this is the
nominal cfm of a given unit, each unit
is capable of producing more cfm, until
something limits the ability of the unit
to meet this higher cfm requirement
such as coil face velocity, filter face
velocity or the outside air inlet hood
eliminator velocity.
The eliminator in the inlet hood is rated
to a maximum of 950 feet per minute.
Above this limit, there is a high
probability of bringing rain water or
snow into the unit, which could migrate
to the conditioned space below. When
selecting units for your application,
remember not to undersize a unit to the
point that the inlet hood eliminators
can not handle the outside air cfm
requirements.
In Table A-4 are the maximum cfm’s for
the inlet hoods on the back and sides of
a mixing module and the side inlet
hoods on an economizer module.
Applications
Table A-4 — Inlet Hood CFM Limitations
Mixing Module Economizer Module
Back Inlet 1 Side 2 Side Single Dual
Unit Size Hood Inlet Hood Inlet Hoods Inlet Hood Inlet Hoods
3 2,337 1,862 3,724 1,862 3,724
6 3,876 1,976 3,952 1,976 3,952
8 4,341 2,384 4,769 2,384 4,769
10 8,949 3,135 6,270 3,135 6,270
12 9,614 3,752 7,505 3,752 7,505
14 10,193 4,314 8,626 4,314 8,626
17 13,870 5,111 10,222 5,111 10,222
21 14,288 5,776 11,552 5,776 11,552
25 17,755 6,773 13,547 6,773 13,547
30 20,786 8,303 16,606 8,303 16,606
35 25,251 9,547 19,095 9,547 19,095
40 28,756 10,858 21,717 10,858 21,717
50 31,825 13,528 27,056 13,528 27,056
66 41,116* 18,078 36,157 18,078 36,157
80 46,217* 21,517 43,035 21,517 43,035
100 57,152* 26,191 52,383 26,191 52,383
*For units with Traq dampers located in the back inlet position of a mixing module, use the two-sided inlet hood limits for
a mixing module.
Example:
Assume you are selecting a #10 exhaust fan economizer unit at 5,000 cfm and .5”
ESP consisting of:
Exhaust damper module
Fan module
Mixing module
Medium access module
Angle filter module
Heating coil module
Cooling coil module
Fan module
Specification requires that no more than 50 percent of the cfm will come from
outside air. In this example, the unit could be supplied with one-sided inlet hood,
as the maximum cfm through one-sided hood is 3,135.
If 100 percent outside air capability were specified, then the unit would need to be
supplied with two-sided inlet hoods.
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