Forum Discussion
mr_andyj
Jun 24, 2021Explorer
I hear the soft start things will help a small generator run an AC that it normally cannot run. There are capacitors that help with the surge of power needed to start the AC compressor, but Im not certain on keeping it running part...
The issue with altitude is the thin air. You might notice your vehicle loses power also, and it probably is able to adjust itself for altitude.
The solution if the soft start does not do the trick is a bigger generator.
If you are at 7500 feet then the gen is sucking in some pretty thin air. It will not have the power needed as it would at sea level, there is no carb adjustment that will give it more power. carb adjustment will only help it run properly, has nothing to do with power.
When there is less air you adj the carb to provide less gas (called leaning it out). The ratio of air to gas must remain the same no matter the elevation, so as you go up into thin air you adjust the carb to a more lean state - aka, less gas. less gas will not give more power, it only keeps the ratio correct and the engine running smooth. Automobiles are set at a 14.7 to 1 air to gas ratio. Im not sure the small engine numbers, probably similar.
I have never HAD to have AC at 7500 feet, esp at night, but I understand wanting to be cool in the day.
I think the formula is 3% for ever 1,000 ft over sea level, so at 7,500 feet this is a 22.5% drop, so multiply by 77.5% and get worse numbers.
3,500 times 0.775 = 2,712.
Congrats, your 3500 watt gen is now a 2700 watt generator!
Now if Im wrong on the math and it is from 4500 feet then 7,500 is 3,000 over 4,500 so 3% times 3 is 9%.
2,500 watt gen times 91% is suddenly 2,275 watts of running power, not 2,500 watts anymore.
3,500 drops to 3,185 and so on....
Again, aside from installing a turbo charger or a super charger there is nothing you can do about the air.
The issue with altitude is the thin air. You might notice your vehicle loses power also, and it probably is able to adjust itself for altitude.
The solution if the soft start does not do the trick is a bigger generator.
If you are at 7500 feet then the gen is sucking in some pretty thin air. It will not have the power needed as it would at sea level, there is no carb adjustment that will give it more power. carb adjustment will only help it run properly, has nothing to do with power.
When there is less air you adj the carb to provide less gas (called leaning it out). The ratio of air to gas must remain the same no matter the elevation, so as you go up into thin air you adjust the carb to a more lean state - aka, less gas. less gas will not give more power, it only keeps the ratio correct and the engine running smooth. Automobiles are set at a 14.7 to 1 air to gas ratio. Im not sure the small engine numbers, probably similar.
I have never HAD to have AC at 7500 feet, esp at night, but I understand wanting to be cool in the day.
I think the formula is 3% for ever 1,000 ft over sea level, so at 7,500 feet this is a 22.5% drop, so multiply by 77.5% and get worse numbers.
3,500 times 0.775 = 2,712.
Congrats, your 3500 watt gen is now a 2700 watt generator!
Now if Im wrong on the math and it is from 4500 feet then 7,500 is 3,000 over 4,500 so 3% times 3 is 9%.
2,500 watt gen times 91% is suddenly 2,275 watts of running power, not 2,500 watts anymore.
3,500 drops to 3,185 and so on....
Again, aside from installing a turbo charger or a super charger there is nothing you can do about the air.
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