Aquatrol Boiler Control Module. Overview Replacement control modules for AQ2000 panels Product Specifications Application Replacement boiler control module for AQ250 Dimensions (in.) 3 1/2 in wide x 2 1/2 in high x 4 1/4 in wide Dimensions (mm) 9 cm wide x 94 cm high x 10.09 cm deep Weight (lb) 0.5 lb Weight (kg) 0.23 kg Approvals, Canadian Standards Association CSA C/US Certified to CSA and UL Standards, File No. LR76030 User Interface DIP Switches Boiler Control Temperature (F) Differential--2 F to 41 F or Auto (minimum 2 minutes on time) Boiler Control Temperature (C) Differential--1 C to 23 C or Auto (minimum 2 minutes on time) Boiler Heat Post Purge Off, 10 seconds to 30 minutes (factory default is 30 seconds) Pump/Valve exercise 30 seconds per 2 weeks of space heating inactivity R-C Input (on Control and Zoning Modules) 24 Vac Class II (input on Control and Zoning Modules) Demand Input Heat Demand (Thermostat R-W) and DHW Demand--External dry contacts connection only B-B Communication Bus Terminals Low voltage, Class II, 2-wire polarity-insensitive, digital communicating link to other Control or Zoning modules. Output Ratings Boiler (T-T)-- 24 Vac, 0.5A, 12VA Electrical Connections Wire-clamp screw terminals, Maximum 2 x 14 AWG each on line voltage terminals Operating Humidity Range (% RH) 5 to 90% RH, non-condensing Temperature Ratings (C) Panel--0 C to 55 C Temperature Ratings (F) Panel--32 F to 130 F