Operating instructions

12 IMM AGSB-60
Case 4, Pit/Solid Wall Installation
Pit installations can cause operating problems and great care should be exercised if they are to
be used on an installation. Recirculation and restriction can both occur. A solid wall
surrounding a unit is substantially the same as a pit and the data presented in this case should
be used.
Steel grating is sometimes used to cover a pit to prevent accidental falls or trips into the pit.
The grating material and installation design must be strong enough to prevent such accidents,
yet provide abundant open area or serious recirculation problems will occur. Have any pit
installation reviewed by McQuay application engineers prior to installation to discuss whether
it has sufficient airflow characteristics. The installation design engineer must approve the
work and is responsible for design criteria.
Figure 12, Pit Installation
Figure 13, Adjustment Factor