T6 PRO Programmable Thermostat, 20-30 Vac, 1 Heat/ 1 Cool Conventional Systems, 2 Heat/1 Cool Heat Pumps, Programmability: 7 Day, 5-1-1 Day, 5-2 Day or Non Programmable, 40-90 Degree Heat Setting, 50-99 Degree Cool Setting, Heat-Off-Cool-Auto-Em Heat System Switching, Auto-On-Circ-Follow Schedule Fan Switching, LED Back Light, Battery or Hardwired, 5 Degree Accuracy, ?? 1 Degree Differential, 5-90 % RH Non Condensing Operating Humidity Range

TH6210U2001 is the direct replacement for 2220NC