Monessen Hearth mhsc eyf24 User Manual

18 

Test Port “OUT”

The heater gas inlet connection is a 

3

/

8

" NPT at the valve. All units  

have the inlet connection on the right side, when you face the unit. 
To connect from the opposite side, route the pipe under the rear 
portion of the unit.
When tightening up the joint to the valve, hold the valve securely 
to prevent movement. 

NPT Test Plug

MANUAL CONTROL (Figure 14)
The pressure regulator is preset and locked to dis-
courage tampering. If the pressure is not as specified, 
replace the regulator with the correct part from the parts 
list in this manual.
Remove 

1

/

8

" NPT plug, located on side of regulator 

body. Install fitting and tubing to pressure gauge. After 
taking pressure reading, reinstall test plug. Check for 
gas leaks.

MILLIVOLT CONTROL (Figure 15)
The valve regulator controls the burner pressure which 
should be checked at the pressure test point.
Turn captured screw counter clockwise two or thre 
turns and then place tubing to pressure gauge over test 
point (Use test point “OUT” closest to control knob). 
After taking pressure reading, be sure and turn captured 
screw clockwise firmly to re-seal. Do not over torque. 
Check for gas leaks.

Test all gas joints from the gas meter to the heater valve for leaks using a gas analyzer or soap and water solution after com-
pleting connection. DO NOT USE AN OPEN FLAME.
Check the gas pressure with the appliance burning and the control set to HIGH.