THRU WALL UNITS 

Thru wall units are an excellent choice for many warehouse applications. They do not require any floor space. Typically, the units are mounted in shipping/receiving areas to address the cold air gain at the dock doors. 

For manufacturing areas, due to the presence of overhead cranes, thru wall units are frequently not a viable option. The clearance required for an overhead crane at the side wall typically does not allow adequate room to install a thru wall unit. 

The heater may have an external gas train. The gas train should be positioned such that the equivalent distance from the outlet of the gas train to the inlet of the heater does not exceed 4 feet. Usually the best location is to place the gas train perpendicular to the side of the heater, so it can be piped directly into the heater’s gas inlet, as illustrated in the S-Series Technical Manual. 

Servicing the unit is another potential problem if overhead cranes are present. Accessing the unit via a boom lift or scissors lift will entail entering crane space. This usually means that the work cannot take place until the crane(s) is locked out or other measures (such as a blocking crane) are taken. Locking out of cranes may seriously affect production, so it should not be taken lightly. 

Servicing the units utilizing a ladder is frequently not an option due to requirements for safe ladder use. In addition, it is difficult, if not impossible, to access several of the heater’s parts from a ladder. 

If a location for a thru wall unit is found, then consideration should be given to the impact on local work stations. What will the mounting height of the heater be? How will the air be distributed? Double deflection grilles are extremely effective when fine tuning air flow. 

Another potential safety issue is whether plant personnel will be regularly traveling or working beneath the suspended load. Additional safeguards may be needed to secure the heater. 

Installing the unit may require barricading the floor area where the installing crew is working. Plant vehicle & pedestrian control must be considered. Flag men may be required. These aspects will need to be covered in the safe work plan. 

Below are installations of thru wall units that were installed several years ago. As always with retrofit installations, final mounting configuration and placement depends on “what the building gives you” with which to work. 

The Cambridge Air Solutions' Applications Engineering Team is available to discuss custom solutions for your project. Have your local rep engage this team for any specific needs you have!