Running AC pump with gas generator

Re: Running AC pump with gas generator

I second Bill's suggestion about adding tank capacity. Either a number of smaller pressure tanks daisy chained together, or a larger cistern or storage tank, then feeding in a pressure tank to feed the house.

The pump will be happier to run with fewer on/off cycles as will the generator. What kills gas engines is starting and stopping. Once they are warm, the wear is very small. Consider for example, running the pump/gennie for 1 hour once a day rather than 15 minutes 4 times a day. You will use less fuel as well in all likelyhood.

Another option is a solar "slow pump" that pumps nearly continuously albeit very slowly. What matters is, the net amount of water you need to be pumped on a daily basis. 250 gallons/day can be had by 5 gpm, for 50 minutes or ~75 gpm for 6 hours. (depends on how deep your well is however)

http://store.solar-electric.com/dasosl.html

http://store.solar-electric.com/grsqpu.html

Re: Running AC pump with gas generator

Look at it this way,,, a pressure tank is nothing but a "wide spot" in the plumbing. As the pump pumps into a (or many) tank(s), it compresses the air (or the bladder in the case of a bladder tank, raising the pressure through out the entire system. So adding a second (or third or fourth) tank merely increases the volume of water under pressure. When you open the tap, the pressure in the tank forces the water out the tap, slowly dropping the pressure. If you look at a P-tank, the water doesn't flow in one side and out the other, but rather it flows into the tank and out at the same point. (a tank tee). Plumbing a number of tanks in the system just adds capacity. The pressure goes up evenly, and down evenly with pumping and draw. Tanks can be located nearly anywhere in the line. (within reason)

A even simpler hot shower system is available from Zodi outback gear. It is a simple copper coil that fits on a camp (or kitchen) stove with a shower head on the one end, and a simple "D" cell pump on the other. Drop the pump in a 5 gallon bucket, hand the head over head (even into a shower enclosure) fire up the stove, and the water comes out as hot as you wish. If it can't get hot enough, you can recirculate the water until it is warmer, and then send it to the shower.

We used one for years in our off grid cabin, drawing water from the frozen lake at -40 to get a good shower all winter. (We preheated the water on the wood stove). A pair of "D" batteries lasts about a month.

A 2600 gallon tank is the functional equivalent of a cistern. Are you filling the tank from a deep well? If so, consider a smaller deep well pump, like the shurflo 9300 if the well is deep. If it is not too deep, consider a Dankof slow solar pump. (See the site host for examples) 600 watts is a pretty big draw off a battery based solar system. A Shurflo 9300 draws ~10 amps (12vdc) and pumps ~3-5 gpm depending on head.

Personally, a single ~ 50 gallon conventional P-tank will provide enough water for most people, with the pump running a few minutes a day. We use a shurflo 9300, into a 50 gallon tank, and we run the pump ~ twice a day. I also wait and turn the pump on in the morning when the sun is up. A 50 gal. pressure tank set at 30-50psi, will deliver water for a good long time after the switch calls for water, so after the last evening shower is done, I turn off the pump, and there is plenty of water to use in the evening and in the morning. If not,,I just turn on the pump breaker,, just load shifting until when the sun is good.
Tony

Re: Running AC pump with gas generator

icarus wrote: »

"When you get battery/solar power you might keep in mind that pumping to 50 psi can takes almost twice the pump run time then a cut off set at 40 psi and you only get about 10-15% more water stored in tank for the 50 psi. I run mine at 20 psi ON, 40 psi OFF settings on pressure switch."

Interesting,, I never thought about it that way, and more correctly, I never did the calc. I have mine set 30-50 with the idea that I can run longer without running the pump. Is it really only ~15% more water? 20 gallons, 15% is 3 gallons, for twice the run time,,,hmmm.

Tony

The other factor is pump/seal/appliance wear. More pressure = more wear

Re: Running AC pump with gas generator

Cariboocoot wrote: »

Non-issue.
Any good generator will supply clean enough power to run a pump; it's just a motor.
I ran my 1/3 HP off the Honda 2000 for two years before I got the solar up to snuff.
Never heard of any seals or anything else blowing because of the AC being supplied by a generator. Unless the gen is a piece of junk, the power will be clean enough. 6kW will certainly run a 1/2 HP pump.

Can you please tell me what 1/3HP pump that was? My new Honda EU2000i wont run my current no name 1/2 water pump. My pump is connected to the bottom of my cistern which sits about 5' below the house. There is a small water/pressure tank attached to the system.