MUA-SVX01A-EN • Direct-Fired Make-up Air
61
Maintenance
Valve Adjustments
MR212 Valve - High Fire Manifold Adjustments
1.
Disconnect wires from amplifier terminal #4 (Modulating Discharge
Temperature-MDT controls), or #2 and #4 (Modulating Room Temperature -
MRT controls). This will cause the valve to call for continuous high fire.
2.
Remove seal cap (A) and turn regulator pressure adjusting screw to obtain
desired manifold pressure (clockwise rotation increases pressure).
3.
Reconnect the wires to amplifier.
Note: If low bypass is on maximum, the desired high fire outlet pressure may
not be achieved.
MR212 Valve - Low Fire Manifold Adjustments
1.
Disconnect wires from amplifier terminal #8. This will cause the valve to call
for continuous low fire.
2.
Remove seal cap (B) and loosen lock screw (C). Turn (D) to desired low fire
adjustment (clockwise rotation reduces minimum flow rate).
3.
Tighten screw (C), replace cap (B) and reconnect wire to amplifier to terminal
#8.
Figure 21. Valve adjustments
Modulator
12
A
A
B
B
C
D
