How To Check Gas Combustion
The combustion testing and adjustments must be performed by a qualified installer, service agency or the gas
supplier. All combustion analyzer must be performed with calibrated equipment to ensure proper reading and
accuracy.
If the combustion levels are not within the range given in Table 1 for the firing rate, shut the unit and contact
Eternal Engineering support team. Failure to comply with this requirement could result in severe personal injury,
death or substantial property damage.
After setting the CO level should not exceed 100 ppm for Natural gas or not exceed 200 ppm for Propane (LPG).
WARNING
!
!
Recommended Combustion Levels
Setting values O
2
/ CO
2
Model
Gas type
Natural gas
Propane gas
O
2
CO
2
O
2
CO
2
GU145(S)
3.0 - 6.5%
8.0 - 10.0%
3.7 - 6.9%
9.0 - 11.0%
GU195(S,M)
3.0 - 6.5%
8.0 - 10.0%
3.7 - 6.9%
9.0 - 11.0%
(Table 1)
52
EC Adapter Cap
Analyzer Probe
Gas Analyzer
Gas / Air Ratio Valve
Inlet pressure port
Adjustment screw A
Manifold pressure port
Please loosen the 1/8" NPT screw and
check the manifold pressure by using a
manometer with 0.01" W.C. resolution.
Min and Max manifold pressures are
indicated on the Eternal OM and Rating
label.
NOTICE
!
Using a combustion analyzer is highly recommended for
checking and setting the negative pressure gas valve.
!
