Question: Does Dwyer offer a low limit switch to protect cooling coils?
Answer: For protecting cooling coils in air handler systems, Dwyer recommends the Low Limit Freeze Protection Switch, Series DFS2. This switch prevents frost build up on coils by sensing the lowest temperature along any one foot section of capillary. The DFS2 units are available with either 10 or 20 ft capillary lengths, for varying application requirements.
The DPDT reset relays (in both manual and automatic models) signal the building management system and cut off the fan. Set points can be adjusted as low as 34°F (1°C) utilizing the visual set point indicator on the unit. Additionally, mounting clips are available as an optional accessory for easy installation.
The Series DFS2 can be used for monitoring HVAC equipment, heat exchangers, and cooling coils. Because of its vapor-filled capillary sensing element, the DFS2 provides excellent anti-freeze functions and detects when temperatures drop below safety values. A joint spring protector provides high durability and ensures flexibility, thus avoiding kinks and breaks in the capillary.
This switch features a removable ABS cover that provides easy access for installation and wiring. When paired with a DPDT switch to provide a secondary alarm to BMS systems, the DFS2 is a great choice to prevent hard shutdown of equipment.
To learn more or order, please visit the Dwyer website.