The manifold gas pressure of the tankless unit can be adjusted by the following procedure.
1) Set up the manometer by following steps 1 through 4 on the “Checking manifold gas pressure” procedures on p. 21.
2) Press and hold down the “MIN” button on the computer board. While holding down the “MIN” button, press either the “INCREASE” or “DECREASE” button to increase or decrease the manifold gas pressure, respectively (Figure 5.18).
3) Refer to the manometer to verify that pressure has been set to desired value.
4) Now press and hold down the “MAX” button on the computer board to change the maximum burn pressure. Repeatedly adjust the minimum and maximum pressures again until both levels are stable and there are no more changes from the previous iteration.
5) After the manifold gas pressure has been set, deactivate the unit (stop all water running through the unit), remove the manometer tube, and replace the port screw.