3000W Chinese Gensets Info.
professor95 wrote: EDIT ADDED 45/5/2013- When this thread started in March of 2005, I never expected to see it survive this long or amass the quantity of information that has been shared here. In...
Forum Discussion
Wgeorge11 wrote:
Why?
The issue is the initial start up load demand. The unit "runs for hours" once it is fired up, but should not require unnecessary running before it's needed. He just needs to follow your instructions to switch from auto to propane, and reduce other power demands until the a-c is going. It doesn't matter how hot it is. It might matter how much demand the battery bank requires for charging.
Please correct me if I'm wrong as I'm no 'lectrician.
Actually, The Wiz has a valid point. I don't have my pressure to temperature tables handy, but as temperature rises so does the pressure of the R-22 used inside the A/C system. There is no unloader - the compressor has to start against whatever head pressure the gas presents. Thus, the hotter it gets outdoors, the higher the head pressure and the power required to start the compressor motor will also increase.
Both high and low pressure sides of the refrigeration system equalize after sitting awhile, but on a day like today the high side could easily reach 300+ PSI and the low side 75 to 85 PSI (45 to 50 degrees) running. BTW, today was the hottest day here in 30 years! The static pressure against the compressor with an equalized system running the above pressures would be about 140 PSI. On a 20 degree cooler day high pressure would be around 225-250 PSI and the low side 65 to 70 PSI (35 to 40 degrees). The static pressure would be about 90 to 110 PSI.
My numbers will be off some since I am calculating from memory but they are close enough to explain what happens.
