Products - Trench Heating
Product Specifications


FRK - Natural Convection
ISAN by Siwa’s FRK trench heaters operate with a natural convection phenomenon. They are usually installed under windows covering the entire perimeter of buildings.

FRK - Natural Convection
Features
- Heating only
- 1/2″ or 3/4″ NPT
- Dust repellent coated heat exchanger
- Same end S/R connections as standard (Opposite end available)
- Customizable dimensions
- Designed to be look continuous (Dummy sections)
Performance
- Max output at 140/120/65°F: 750 BTUh/ft
Dimensions
- Height Range: 3.1″ to 7.9″
- Grille Width Range: 9.8″ to 16.7″
- Max length/unit: 189″ (15.75′)
Dowloads
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Common Applications
FRK - Natural Convection
ISAN by Siwa’s FRK trench heaters operate with a natural convection phenomenon. They are usually installed under windows covering the entire perimeter of buildings.
Trench heaters advantages :
- They act as a thermal barrier that minimizes the flow of cold air from the window surface into the design area
- A portion of the warm air is directed into the space to heat the common area. This exponentially reduces the heating load on other building equipment
- The trench heaters can used as supplementary heating to other types of systems (fan coils, heat pumps, VRF’s, forced air)
- If the heat output of the trench heater is sufficient, the trench heater may also be used as the main heating system
- These trench heaters are also suitable to adjust temperatures in entrance halls, commercial areas and long corridors
- Other common applications include: Hotel lobbies, condo suites, condo lobbies, amenities, community centers
The great range of the heights and widths of the trench heaters gives the designer many options how to fit the model with the required output in the configuration of the floor.

Batavia Place - Condo
SIWA References
This condo project features Polar air‘s low-profile, ducted 2-pipe fan coils (PDWAs), selected for their efficiency and compact design to meet the building’s heating and cooling needs.
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