16. Turn on the electric power and gas supply to the boiler.
17. Reset the low pressure switch. For instructions, see Resetting the gas high / low pressure
switches on page 77.
18. Tune the gas valve. For instructions, see Adjusting the gas valve (EX 400, EX 500) on page
74.
7.3 Replacing the fan, gas valve, and burner in EX 750
and EX 800 models
This section documents the following maintenance procedures for EX 700 and EX 850 models:
Replacing the fan
Replacing the gas valve
Replacing the burner.
Fan
Mixing device
High pressure switch
Three- (3) wire Molex plug
Section: Service and maintenance