7.2.2 General boiler maintenance 72
7.3 Replacing the fan, gas valve, and burner 76
7.3.1 Replacing the fan 78
7.3.2 Replacing the gas valve 79
7.3.3 Replacing the burner 80
7.4 Cleaning the sight glass 81
7.5 Cleaning the condensate trap 82
8.1 Electronic components 85
8.1.1 Temperature sensors 85
8.1.3 Water pressure sensor 86
8.1.4 Safety and Ignition Module (SIM+) 87
8.2 Troubleshooting error messages 89
8.2.1 Maximum ignition trials error 89
8.2.2 Hi Limit cut-off temperature error 90
8.2.3 Low Water Cut-off error 90
8.2.4 Aux. Interlock 1 or 2 90
8.3 Miscellaneous touchscreen controller errors 91
8.3.2 Temperature issues 93
8.3.3 Miscellaneous issues 94
Boiler part diagrams - VX 110, VX 150, VX 199 100
Installation & Commissioning Report 105