Trane RT-PRC010-EN Application Considerations, Horizontal Discharge, SXHF, SFHF, SLHF, SSHF Units

Application Considerations

Horizontal Discharge

The typical rooftop installation has both the supply and return air paths routed through the roof curb and building roof. However, many rooftop installations require horizontal supply and/or return from the rooftop because of a building’s unique design or for acoustic considerations.

Trane has two ways to accomplish horizontal supply and/or return.The first applies to all IntelliPak® Rooftop units. Special field supplied curbs are installed that use the unit’s standard discharge and return openings.The supply and return air is routed through the curb to horizontal openings on the sides of the curb.The second method available for horizontal supply and return applies to

20 - 75 tons SXHF, SFHF, SLHF, SSHF, and

90 - 130 tons SXHG, SLHG and SSHG design units ONLY. With this method the standard discharge and return openings are blocked in the field. Access panels are removed as indicated in Figures AC-1 and AC-2.These openings are used for the discharge and return. No special curb is needed.

SXHF, SFHF, SLHF, SSHF Units

Figure AC-1 is a simplified sketch of the rooftop showing which panels can be used for horizontal supply and/or return. To supply air horizontally, the panels that normally house the heat accessory controls (Panel A) and the gas heat barometric dampers (Panel B) can be removed and either of the openings

used as a unit discharge (see note 1).To return air horizontally, the exhaust fan access door (Panel C) can be removed and used as a return opening.Tables AC- 1, 2 and 3 show dimensions for those panels.

Horizontal Discharge on SXHF, SFHF, SLHF and SSHF Rooftops (20 to 75 tons)

The SXHF (extended casing cooling only), SFHF (gas heat), SSHF (steam heat) and SLHF (hot water heat) rooftops can be field modified to supply and return air horizontally without the use of a horizontal supply/return curb.

To supply air horizontally on SXHF only, the panels that normally house the heat accessory controls (Panel A) and the gas heat barometric dampers (Panel B) can be removed and either of the openings used as a unit discharge.To return air

Figure AC-2 Horizontal Discharge Panel Dimensions — 20 - 75Tons SXHF, SFHF, SLHF, SSHF Units

Note: Cannot remove Panel A for horizontal discharge on SFHF, SLHF, SSHF Units.

horizontally, the exhaust fan access door (Panel C) can be removed and used as a return opening.

1.For horizontal discharge on SFHF, SLHF and SSHF units, only the Panel B can be removed. Panel A cannot be used due to the location of the heating coils.

2.For horizontal discharge on SFHF (gas heat) models, the block off under the heater must be removed. After removal, a support must be added for the drain tube.

3.Supply and Return Base openings must be covered when converting to a horizontal configuration.

Table AC-1 — SXHF, SFHF, SSHF, SLHF —					Table AC-2 — SXHF, SFHF, SSHF, SLHF —					Table AC-3 — SXHF, SFHF, SSHF, SLHF —
	Panel A and B Dimensions					Panel C Dimensions					X,Y and Z Dimensions
			Total Area (H X W)					Total Area (H X W)
Model	H (in.)	W (in.)	(in.2)	(ft2)	Model	H (in.)	W (in.)	(in.2)	(ft2)	Model	X (in.)	Y (in.)	Z (in.)
S*HF C20	40.7	25.5	1038	7.2	S*HF C20	40.7	34.5	1404	9.8	S*HF C20	35.5	44.0	201.5
S*HF C25	40.7	25.5	1038	7.2	S*HF C25	40.7	34.5	1404	9.8	S*HF C25	35.5	44.0	201.5
S*HF C30	52.7	25.5	1344	9.3	S*HF C30	52.7	34.5	1818	12.6	S*HF C30	35.5	56.0	201.5
S*HF C40	64.5	34.5	2225	15.5	S*HF C40	64.5	34.5	2225	15.5	S*HF C40	44.5	67.8	237.0
S*HF C50	76.7	34.5	2646	18.4	S*HF C50	76.7	34.5	2646	18.4	S*HF C50	44.5	80.0	237.0
S*HF C55	76.7	34.5	2646	18.4	S*HF C55	76.7	34.5	2646	18.4	S*HF C55	44.5	80.0	237.0
S*HF C60	64.6	34.5	2229	15.5	S*HF C60	64.6	34.5	2229	15.5	S*HF C60	44.5	68.0	237.5
S*HF C70	64.6	34.5	2229	15.5	S*HF C70	64.6	34.5	2229	15.5	S*HF C70	44.5	68.0	237.5
S*HF C75	64.6	34.5	2229	15.5	S*HF C75	64.6	34.5	2229	15.5	S*HF C75	44.5	68.0	237.5
Notes:					* = X, F , L, or S

1.Add an extra 0.20-inches pressure drop to the supply external static to account for the extra turn the air is making.

2.The openings all have a 1.25-inch lip around the perimeter to facilitate ductwork attachment.

3.If exhaust fans are being used, provisions should be made for access to the exhaust components, since the access door is now being used as a return.

4.Use the dimensions provided and the supply Cfm to calculate the velocity (ft/min) through the openings to be sure they are acceptable.

RT-PRC010-EN 11