Checking The Gas Pressures - A.O. Smith BFM 30 Installation Instructions Manual

2.5 Checking the gas pressures

The nominal load has been set at the correct value in
the factory. A further check of the pressure should be
carried out during the commissioning of the unit.
A dangerous situation can occur if the following
instructions are not followed carefully. Setting the
nominal load is possible as there is a burner pressure
control. If you wish to adjust the burner pressure the
following procedures must be followed:
1. Switch off main power by turning the I/O switch to '0'
position.
Figure 14 - Checking the gas pressures
20
2. Connect the U-tube manometer to pressure nipple B.
3. Switch on main power and ensure temperature
control is calling for heat.
4. Wait until water heater is firing.
5. Check pressure against table on page 10 for relevant
gas and adjust at main gas valve.
6. Switch of main power as no. Y.
7. Remove U-tube manometer and close pressure
nipple.
8. Switch on main power and test for gas tightness and
correct operation, (Figure 14).