Lennox ML193UHE Series Unit Information page 42

Manifold Pressure Measurement
Follow the steps below and use FIGURE 56 as a reference. Gas manifold Kit 10L34 provides additional components if
needed.
1 - Connect the test gauge positive side "+" to manifold pressure tap on gas valve.
2 - Tee into the gas valve regulator vent hose and connect to test gauge negative "-".
3 - Start unit and let run for 5 minutes to allow for steady state conditions.
4 - After allowing unit to stabilize for 5 minutes, record manifold pressure and compare to value given in table 19.
5 - Shut unit off and remove manometer as soon as an accurate reading has been obtained. Take care to replace
pressure tap plug.
6 - Start unit and perform leak check. Seal leaks if found.
2" Long Square Tubing
(remove for manifold adjustment)
Gas Valve Regulator
Vent Hose
(to burner box)
Barbed Fitting
10" Long
Square
Tubing
Measuring Device
FIGURE 56
(+)
(−)
Tee
Page 42
Negative Barbed Fitting
(remove for manifold adjustment)
Manifold Pressure Outlet