Armstrong, Water Heater, models:

Digital-Flo DF41540	Installation, Operation & Maintenance Manual
Digital-Flo DFS1540	Users Installation Operation & Maintenance Manual
Flo-Direct	Installation Manual
Flo-Direct 2.0 AFD-1000	Installation, Operation And Maintenance Manual
Flo-Direct AFD-1000	Installation, Operation And Maintenance Manual
response 2000	Installation & Operating Instructions