Condensate Drains Ð Pipe nipples covered with foam rubber insulation are shipped in unit return air ®lter section (6 nipples in units 48MA, 4 nipples in units 50ME). Install a nipple in each drain connection on both sides of unit. See Fig. 1 and 2 for drain locations. Be sure foam rubber seals space between nipple and base rail opening to prevent rain leaks.
Connect a drain line to drain connection under outdoor air inlet grilles on both sides of unit. These drains need not be trapped.
Install a trapped drain line on remaining connections on lowest side of unit depending on unit pitch. If unit is level, a trapped drain may be installed at each connection if de- sired. Cap or plug unused connections on high side of unit to prevent air¯ow between unit interior and outdoors.
OUTDOOR AIR INLET |
| |
(ONE ON EACH SIDE OF UNIT) | FLUE OUTLET | |
SHIPPING SHIELD | ||
COVER | ||
(BEHIND LOUVERS) | ||
(48MA ONLY) | ||
|
Fig. 6 Ð Shipping Shield Locations
(016-030 Units Shown)
Do not interconnect drains. Make each trap a minimum of
4 in. deep. Insulate trap against
Gas Piping (48MA) Ð Unit is equipped for use with type of gas shown on nameplate. Refer to latest edition of ANSI Z223.1. Unit main gas connection and alternate gas connection locations are shown in Fig. 1, 4, and 8. Do not use gas supply pipe smaller than unit gas connection. Maxi- mum allowable natural gas supply pressure is 10.0 in. wg; minimum allowable natural gas supply pressure for full rate input is 5.0 in. wg.
Pitch pipe 1¤4 in. per 15 ft. Pitch all horizontal pipe runs upward to risers and from risers upward to meter. Install a dirt and moisture pocket (drip leg) at each section of vertical pipe run. Use only ground joint unions to ensure leakfree joints. Use only pipe joint compounds that are resistant to the action of lique®ed petroleum gases.
NOTE: Dimension to suit job requirements. Twelve inches will bring duct plenum to bottom of roof curb.
DIMENSIONS (in.)
UNIT | 016,024 | 028,030 | 034,040 | |
48MA,50ME | ||||
|
|
| ||
A* | 75¤8 | 75¤8 | 75¤16 | |
B* | 75¤8 | 73¤4 | 53¤4 |
*Typical; both ends.
Fig. 7 Ð Field-Fabricated Zone Duct Plenum Detail
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