Versatility in Refrigerant Monitoring

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What do you do when the job you are bidding calls for a refrigerant leak detector in the mechanical room? Do you just figure in an RLD-5 or RLD-134A solid-state refrigerant leak detector from Kele ? After all, these two devices will monitor six of the most common refrigerants used today. ThatÕs great....unless the chiller happens to use R-123 refrigerant.

ASHRAE 15-1994 (Safety Code for Mechanical Refrigeration) requires "a detector, located in an area where refrigerant from a leak will concentrate, which shall actuate an alarm and mechanical ventilation....at a value not greater than the corresponding TLV-TWA* (or toxicity measure consistent therewith)." This standard also references a toxicity/flammability matrix in ANSI/ASHRAE 34-1992 to determine safety groups of refrigerants. All the refrigerants monitored by the RLD-5 and RLD-134A are in the "Lower Toxicity" category. However, R-123 is in the "Higher Toxicity" category, and this is where the problem arises. Since R-123 is more toxic, its refrigerant leak detector must alarm at lower levels than those required for the RLD-5 and RLD-134A.

In the past, expensive industrial type stand-alone systems were the only solution for monitoring R-123 and alarming at the low ambient levels required, typically 30 ppm (parts/million). These units utilized small fans to pull samples into the sensing chamber and required sampling tubes to be run from the mechanical rooms. They were large, heavy and difficult to install. Kele now has a better solution! The new RLD-IR Series Infrared Refrigerant Gas Sensor is specifically designed to interface with your building automation system. The RLD-IR is installed in the area to be monitored. The standard 4-20 mA and 0-10 VDC outputs are proportional to 0-1000 ppm refrigerant and may be used to tell your controller if there is refrigerant gas in the ambient air. A DPDT alarm relay set at 30 ppm for R-123 or 200 ppm for R-11, R-12, R-22, or R-134a is also included, and may be used as a digital input to a controller, or to actuate the alarm and mechanical ventilation. The LCD display on the front of the unit indicates refrigerant gas concentration in ppm. The RLD-IR Series is available for use with R-123, as well as R-11, R-12, R-22, or R-134a, and may be specially ordered for other refrigerants.

With the spiraling cost of refrigerants, the RLD-IR Series can help you sell your building automation system, even if ASHRAE Standards are not a concern. Simply monitoring refrigerant levels in the equipment room and notifying the building owner of a leak before the refrigerant charge is lost can save thousands of wasted dollars - a great return on investment for your customer! So the next time you need to monitor refrigerant, there is no need to buy an expensive stand-alone system. Utilizing the RLD-IR as an input to your automation system will provide central monitoring capability and put you in control.

What if you want to use the RLD-IR in multi-point applications and do not want to dedicate multiple BAS controller inputs to the application? No problem! A Model VA-201C Network Controller may be connected to up to 32 RLD-IR's monitoring a variety of refrigerants. The VA-201C will provide visual and audible alarms, alarm relays, and an alphanumeric display, that indicates the location of the transmitters being monitored, their status, and the refrigerant being monitored.

The next time your project calls for refrigerant monitoring, whether solid-state or infrared, single point or multi-point, keep the RLD Series refrigerant leak detector in mind. It's just one more
example of the value you will find in Kele's products.