MR510 Maxitrol 3/4 Inch MODULATOR REGULATOR Maxitrol MR510 Great Wholesale Prices! Maxitrol Selectra Modulation. Maxitrol was founded in the 19th century in Germany and has a long history in the design of innovative technology in the oil and gas industry. Maxitrol (Mertik) has more than 250 patents in 30 countries and has a worldwide distribution. ITT Controls can also deliver Maxitrol products. description. new, maxitrol, selectra, mr510, gas valve, 24 vdc, .5 amp. part in new condition. not in original packaging. the Maxitrol Selectra® system. (See Exa Star modulating valves or ratio (zero) regulators for these applications.) DIRECT FIRED Valves designed for direct fired applications (negative pressure/pull through) M411, M511, M611, MR212D, MR212E, MR212G, and MR212J. These valves are designed exclusively for negative pressure (pull G. H. I. *Control circuits external to the Series 21 can cause burner malfunction. Always check manual valve to be certain gas is on, and check limit controls for normal operation. 23. If erratic or pulsating DC voltage is observed and wiring shows no defects, replace amplifier. If erratic or pulsating voltage continues, contact Maxitrol Maxitrol's Selectra systems can be used in direct and indirect fired gas applications. Selectra's unique electronic Modulator or Modulator-Regulator valves control gas flow with instantaneous response and continual adjustment. They are the superior alternative to modulator motors and butterfly valves. Find best value and selection for your MAXITROL SELECTRA A200 SIGNAL CONDITIONER NEW search on eBay. World's leading marketplace. MR212D Maxitrol 1 1/2" NPT Modulating Gas Valve and Regulator for Direct Fired (Negative Pressure) Burners with 5 PSI Inlet Pressure Max. Note: MR212D 1-1/2". The "1212" is reference code for the pipe size which would be 1-1/2" G. H. I. *Control circuits external to the Series 20 can cause burner malfunction. Always check manual valve to be certain gas is on,