24"
DUCT TRANSITION
DUCT
AIR |
| |
OUTLET |
| |
| FLANGED DUCT | |
BLOWER | CONNECTION | |
(FIELD | ||
GASKETS | ||
FABRICATED) | ||
(BY INSTALLER) | ||
|
FIGURE 13 - SUGGESTED METHOD FOR CONNECTING DUCTWORK
RETURN AIR DUCT ANGLES
Return air duct angles are shipped turned in. They are intended to be unscrewed and turned for connection of duct- work. The return air grille accessory attaches in the same manner as the panels.
DRAIN CONNECTIONS
All drain lines MUST be trapped and located so they will not be exposed to freezing temperatures.
The evaporator blower has 7/8" OD steel condensate stub at each end of a single drain pan. Both ends are closed with plastic caps. A plastic or rubber ell can be used. (Field sup- plied) Attach the ell to the desired end and run a full size 7/8" drain line to the nearest drain facility. Seal the cap at the unused end with suitable mastic.
Drain piping should be constructed as shown in 14. The 3- inch dimension must equal or exceed the negative static pressure developed by the supply air blowers. If it does not, the condensate will not drain properly and may overflow the drain pan. The trap must be at least
FIGURE 14 - RECOMMENDED DRAIN PIPING REFRIGERANT MAINS
Hard drawn copper tubing should be used where no appre- ciable amount of bending around pipes or other obstructions is necessary. Use long radius ells wherever possible. If soft copper is used, care should be taken to avoid sharp bends that may cause a restriction.
Where refrigerant lines pass through a wall, pack fiberglass insulation and a sealing material such as permagum around the refrigerant lines to reduce vibration and to retain some flexibility in the lines.
16 | Unitary Products Group |