Trane Fan manual Selection Procedure

Selection Procedure

1

Select the type of fan desired. The Super Q II should be used where fan radiation noise needs to be attenuated.

2

Position the Q fan to deliver air to the system and minimize adverse Kt effects. Straight-thru flow arrangements are best.

3

Select the desired Q fan or Super Q II fan options.

4

Compute the fan external static pressure and cfm requirements.

5

Determine which Kt effects apply to the Q fan installation.

6

If the Q fan is serving a VAV system, select AC frequency drive or inlet vane modulations. (AC frequency drive modulation is considerably quieter and more efficient than Q fan inlet vanes.) Super Q II fans use AC frequency drive modulation only.

7

Input the selection parameters into the Trane fan selection program and select the desired Q fan or proceed with a manual selection.

8

Manual Selection: a

Determine the air density ratio if non- standard air is being handled by the

Qfan.

b

Adjust the external sp by the air density ratio.

c

Use the inlet and outlet area of the fan to calculate the inlet and outlet velocities. Use these velocities and the inlet and outlet Kt to correct the external static pressure to the right value. Reselect the fan at the right value.

d

From the performance table, select the desired fan.

9

If inlet vane modulation was selected, increase the rpm by 1 percent and increase the bhp by 3 percent.

10

If the air density ratio is nonstandard (different than 1.00), the rpm is correct and the bhp must be multiplied by the air density ratio.

11

If the start-up air temperature is lower than the normal operating temperature, adjust the fan curve bhp for the starting temperature. The next larger nominal hp motor is the correct motor size.

12

If exceptional quiet is desired, choose a short or long Q fan plus duct silencer. The plus silencer is a low turbulence, low pressure drop, high attenuation duct silencer. Subtract the attenuations given inTables S-1 and S-2 from the Q fan/Super Q II fan sound power projections. If silencer regenerated noise is a concern, contact your local Trane sales engineer for further information.

Table S-1 — Short Plus Silencer Attenuation (1D Length)*

Q-Fan Sound Power By Octave Band At Nominal Cfm/SP

Fan Size	63 Hz	125 HZ	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz	8000 Hz
16	2	3	10	16	19	20	13	12
19	2	3	10	16	19	19	13	12
21	2	4	10	16	19	19	13	11
24	3	4	10	16	19	19	13	10
27	3	5	10	16	19	19	13	9
30	4	5	10	16	19	17	13	9
36	4	6	10	16	19	15	13	9
40	5	6	11	16	19	14	12	9
44	5	6	11	16	19	14	11	9

Table S-2 — Long Plus Silencer Attenuation (2D Length)*

Q-Fan Sound Power By Octave Band At Nominal Cfm/SP

Fan Size	63 Hz	125 HZ	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz	8000 Hz
16	3	6	19	32	37	39	26	24
19	3	6	19	32	37	37	26	24
21	4	7	19	32	37	37	26	22
24	5	8	19	32	37	37	26	20
27	6	9	19	32	37	37	26	18
30	7	9	20	32	37	34	26	18
36	8	11	20	32	37	30	25	18
40	9	11	21	32	37	28	23	18
44	9	12	21	32	37	28	22	18

*Approximate attenuations. Use theTrane Fan Selection Program for attenuation predictions that include silencer regenerated self-noise.

NOTE: Super Q II not available with Class III fans.

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