The Series 3 electronic gas modulation system can easily turn a two-stage indirect-fired furnace into a modulating furnace, the company states. It can achieve constant discharge air temperatures as well as a 25-percent or low turndown ratio, says the manufacturer. The electronics and modulator/modulator-regulator valves are designed to maintain control of discharge air temperature. Supplied with the Series 3 are an amplifier, temperature dial, sensor with mixing tube, and a modulating gas valve. The Series 3 can be used for duct furnaces, indirect make-up air heaters, and commercial furnaces.
Maxitrol Co., 23555 Telegraph Rd., P.O. Box 2230, Southfield, MI 48037; 248-356-1400; 248-356-0829 (fax); email@example.com; www.maxitrol.com.