RTC/RETURN TEMPERATURE CONTROL IS DESIGNED TO OPERATE 3-WAY OR A 4-WAY VALVE TO PROTECT BOILER AGAINST FLUE GAS CONDENSATION AND THERMAL SHOCK, COUNTS BOILER RUN TIME, COUNTS THE NUMBER OF BOILER CYCLES, COUNTS BOILER COLD SHOCKS, WARNS OF COLD BOILER RETURN TEMPERATURES, TEST SEQUENCE TO ENSURE PROPER OPERATION, CSA C US CERTIFIED, OVERALL DIMS:7"H x 7-1/2"W x 2-1/4"D, ORIGIN:USA
