Toshiba TRANQUILITY 20 manual ClimaDry Reheat Coil Pressure Drop TS Units PSC Motor, Example

Table 7: ClimaDry Reheat Coil Pressure Drop - TS Units (PSC Motor)

Coil Face		TSH/V/D with Reheat ESP Loss
	TSH/V/D	TSH/V/D	TSH/V/D	TSH/V/D	TSH/V/D
Velocity
FPM	018	024, 030	036	042, 048	060, 070
	In. of Water	In. of Water	In. of Water	In. of Water	In. of Water
200	0.037	0.033	0.031	0.028	0.026
250	0.052	0.046	0.042	0.038	0.034
300	0.077	0.066	0.059	0.051	0.044
350	0.113	0.096	0.085	0.073	0.061
400	0.181	0.160	0.145	0.131	0.117
450	0.242	0.226	0.215	0.205	0.194
500	0.360	0.345	0.335	0.326	0.316

For TS units with ClimaDry Reheat coil applications, calculate face velocity of the entering air. From the table above, find ESP for Reheat application. The loss includes wet coil loss.

Example:

Reheat coil pressure drop can be determined from the above table. Coil velocity (FPM) = Airflow (CFM) / Face Area (sq. ft.).

1)TSH036 has a face area of 4.86 sq. ft. (see physical data table in I.O.M.).

2)At 1,100 cfm, coil velocity (FPM) = 1,100 / 4.86 = 226 FPM.

3)From above table, it will be necessary to subtract 0.037 from the blower performance ESP.

4)On medium speed, the TSH036 (without reheat - see blower table) can deliver 1,100 CFM at 0.28 in. wg. with the standard PSC motor; with the reheat coil, it now delivers 1,085 CFM at 0.28 in. wg. or 1,100 CFM at 0.24 in. wg.

5)If the decrease in airflow is acceptable, no changes are necessary. Otherwise, high speed fan should be used to overcome the pressure drop of the reheat coil.

Table 8: TS Air Coil Face Area

Model	018		024				030		036				042		048				060			070
	Horiz.	Vert.	Horiz.	Vert.		Horiz.		Vert.	Horiz.	Vert.		Horiz.		Vert.	Horiz.	Vert.		Horiz.		Vert.	Horiz.		Vert.
Coil Face	3.38	3.33	3.88		3.89	3.88		3.89	4.86		4.86	5.56		5.56	5.56		5.56	6.25		6.25	6.25		6.25
Area, sq. ft.
	(0.3135)	(0.3097)	(0.3600)	(0.3613)		(0.3600)		(0.3613)	(0.4516)	(0.4516)		(0.5161)		(0.5161)	(0.5161)	(0.5161)		(0.5806)		(0.5806)	(0.5806)		(0.5806)
(sq. m)

ClimaDry Whole House Dehumidification - ClimateMaster Geothermal Heat Pumps - Rev.: 18 April, 2008B

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