* Reduction of the air ratio (reduction of O2% in the exhaust gas) reduces heat loss with the exhaust gas.
* This in turn leads to fuel saving.
* The graph illustrates result of air ratio reduction.
* In fuel saving rate, 13A gas and fuel oil A differ only very little.
* At lower exhaust gas temperatures, the effect is small.
*(Example)

If air ratio can be reduced from the present 1.6 (O2 = 8.4%) to 1.2 (O2 = 3%), a fuel saving of 2.8% is realizable.