Operating cost of optional larger pump?

[RAK]

I'm replacing a 35 yr old 3/4hp Franklin/Aermotor Pump and considering upgrading to a 1hp. The 3/4 pump worked fine (I don't know what the performance curve was) to supply two residences and some irrigation. But we live in a wildfire area and may want a fire protection ("Halo") system that would require increased volume from current use. So the question regards power consumption and the judgment of whether the larger pump is worth the increased operating cost for the sole purpose of an unlikely but still possible future wildfire? If two pumps of similar efficiency, operating well within their best efficiency range, are operating at the same volume and pressure, does the 1hp use "significantly" more electricity than the 3/4? We pump from an 8" well, 185 ft deep, pump set at 100', water level at 30' with about a 5' drawdown after 3hrs at 27gpm. We pump at 40-60psi and have an 85 gal hydro tank. Also, for extended (6hr+ @ 12gpm) irrigation operations, would a CSV be beneficial? Thanks.

 

[Valveman]

A 1HP is just as efficient as a 3/4HP. It will just supply the same amount of water in 25% less time. The problem is that it will supply the same amount of water in 25% less time. Lol! All that means is that it will quickly fill the pressure tank and cycle off. Because cycling is so bad for the pump, adding a Cycle Stop Valve is a good idea. The CSV will still let the pump produce max flow when needed, but keeps it from cycling itself to death the rest of the time when smaller amounts of water are being used.

I worry that a 27 GPM, 1HP will not build enough pressure to shut off a 40/60 switch? Do you have a pump model or curve?

 

[Sponsor]

 

[Reach4]

We pump at 40-60psi and have an 85 gal hydro tank. Also, for extended (6hr+ @ 12gpm) irrigation operations, would a CSV be beneficial? Thanks.

If you actually use 12 gpm and the pump puts out 22 gpm, then the CSV would be very useful. If your pump puts out 12 gpm, and the pressure settles at 55 psi during irrigation, then the irrigation would do fine without the CSV.

If this was new construction, they might have required you to fill a 10000 gallon tank for fire engines to pump from.

 

[RAK]

A 1HP is just as efficient as a 3/4HP. It will just supply the same amount of water in 25% less time. The problem is that it will supply the same amount of water in 25% less time. Lol! All that means is that it will quickly fill the pressure tank and cycle off. Because cycling is so bad for the pump, adding a Cycle Stop Valve is a good idea. The CSV will still let the pump produce max flow when needed, but keeps it from cycling itself to death the rest of the time when smaller amounts of water are being used.

I worry that a 27 GPM, 1HP will not build enough pressure to shut off a 40/60 switch? Do you have a pump model or curve?

View attachment 101428

A 1HP is just as efficient as a 3/4HP. It will just supply the same amount of water in 25% less time. The problem is that it will supply the same amount of water in 25% less time. Lol! All that means is that it will quickly fill the pressure tank and cycle off. Because cycling is so bad for the pump, adding a Cycle Stop Valve is a good idea. The CSV will still let the pump produce max flow when needed, but keeps it from cycling itself to death the rest of the time when smaller amounts of water are being used.

I worry that a 27 GPM, 1HP will not build enough pressure to shut off a 40/60 switch? Do you have a pump model or curve?

View attachment 101428

I've attached the curves. 1 and 2 represent normal peak demand and fire suppression demand, respectively. The blue line represents the 120 ft TDH we normally pump at peak demand with a 40-60 cut off. (35 ft to water + 40 psi). The 27gpm figure was just a drawdown test we did a couple years ago and was limited by the pump capacity and not the well. It seems like there's not significant additional power consumption (cost) from using the 1hp pump and benefiting from the additional "headroom" it provides in the unlikely event of a fire. Intuitively it seems like, with similar pump sizes and efficiencies, the power consumption is mostly load-dependent and not hp rating dependent. Is that about right? Also, as I understand it , the CSV valve, if set to limit at 50psi, prevents the pump from cutting out during extended irrigation runs but then "resets" after the demand drop at the end of the run thus allowing the pressure to rise back to the 60psi cut out. It's clear this would prevent recycling and allow for more accurate adjustment of sprinkler radius. Would it also affect power consumption? Also, I have and additional 85 gal hydro tank I'll probably add to the system. This all may seem like a trifle but we're on a 2-home shared system and I have to justify upping the hp to our neighbors who are very budget conscious and don't care much about the fire suppression issue ...they plan to just bug out as the 100ft flame front approaches whereas I, on the other hand, am largely unburdened by common sense and plan to stay and (sorta) fight it. Thanks again for your help on this.

 

[Valveman]

The 18GS10 is a good choice, as it will make plenty of pressure for the pressure switch. However, as you can see in the curve (thanks for that btw), it still makes 140' of head (60 PSI) even when pumping max demand of 23 GPM. That means the pump will cycle on and off between 40 and 60 for every demand you have between 2 GPM and 23 GPM. The CSV12550-1 will hold at 50 PSI constant all through that range and not let the pump cycle off at 60 while water is being used. The CSV1A should be set to hold 60 PSI constant when using small amount of water like a single shower, as it will drop 10 PSI and only hold 50 PSI when running max demands. Either CSV will work.

Power consumption is somewhat load dependent as the pumps amps will decrease as the CSV restricts flow to match a small demand. Goulds pumps will drop about 30% in amps when restricted. However, the drop in amps is not linear with the decrease in flow, so it is always most efficient to use the pump close to max flow when irrigating or doing any long term watering.

With the CSV even running both houses and the fire sprinkler system a 10 gallon size pressure tank is all that is needed. The CSV will work fine with one or even two of the big 80 gallon size tanks, but they are not needed. When water is being used for any length of time the CSV causes it to bypass the pressure tank and go directly to the faucet/sprinkler. etc. Pressure tank size is a moot point except for needing a little for the ice maker or rinsing a toothbrush without needing the pump to come on.

Setting the CSV with a large tank means adjusting it to 58 PSI when using a 40/60 switch. In that way the big tank fills to 58 before the CSV starts working. Then after any water use the CSV only needs to fill the last 2 of the 20 gallons is an 80 gallon tank, which will give the pump about a 2 minute run time. Some people think you cannot use a large tank with a CSV as they believe it will take a long time to fill the tank. Lol!

 

[Valveman]

Looking back, with a pumping level of 30' deep that pump MIGHT not cycle at 23 GPM. But any flow rate less than that will cause it to cycle on and off unless you have a Cycle Stop Valve.

 

[Bannerman]

Some people think you cannot use a large tank with a CSV as they believe it will take a long time to fill the tank.

On the contrary, using a large tank will signify a greater amount of water will need to be consumed before the pressure drops sufficiently to cause the pressure switch to activate the pump.

Because a CSV only regulates the flow from the pump, the pump will need to be active for the CSV to provide constant 50 psi (or other pressure) to fixtures.

With a small pressure tank such as the recommended 10-gallon tank, only ~2.5 gallons will need to be consumed before the pump becomes activated. This is compared an 80-gallon pressure tank which will supply ~20 gallons at a declining 60>40 psi before the pressure switch activates the pump to obtain 58 psi constant from the CSV.

 

[2stupid2fixit]

A 1HP is just as efficient as a 3/4HP. It will just supply the same amount of water in 25% less time. The problem is that it will supply the same amount of water in 25% less time. Lol! All that means is that it will quickly fill the pressure tank and cycle off. Because cycling is so bad for the pump, adding a Cycle Stop Valve is a good idea. The CSV will still let the pump produce max flow when needed, but keeps it from cycling itself to death the rest of the time when smaller amounts of water are being used.


View attachment 101428

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[2stupid2fixit]

I have a bunch of posts on here that give time stamps where I bought and installed a $160 (i think) 3/4 hp ebay chinese pump to replace my 1974 made Franklin/Goulds 1/2 hp pump. I notice no difference in electric bill. The folks in this forum told me that using a 3/4 horse pump in 2018 was probably the same as using a 1/2 horse in 1974 due to the changes in they way horsepower was and is now measured. A sidenote, how the hell is horsepower a measure of anything? I had two quarterhorse geldings that were from the same sire and dam, brothers. One was strong and reliable but the other one was stronger but lazy as alll hell. So did i have 2 horse power from my two horses or did I have 1.6 horsepower because one of them was a stump puller but only if he was feeling it that day? The stronger horse had lots of opinions on doing any kind of work. Enough about horses, horsepower is a poor unit of measurement. Also, dont install a $160 chinese pump. While mine has been nothing but perfect, I know someday I will have to yank it upo 200 feet all by myself and install a new one. If you are paying someone to hang a pump you will want a reputabe quality pump down there, if there even is such a thing these days. If changing out pumps doesnt bother you and you enjoy DIY, by all means buy the cheapest piece of siht pump on ebay you can find. If you want to conserve electricity resources, Valveman is correct, you will want a cyclestop valve, because without it, a bladder tank and pressure switch system will cycle the pump on and off. That's how that system is supposed to work. Cycling on and off means that the pump has to start from a dead stop, capacitor or not, to reach operating RPMs which means more power consumption. Its more economical to keep a motor running than to start and stop it repeatedly. Also, these cycles are what destroys your pump. Dont take my word for it, you can measure yourself how much current a stopped motor/impeller assembly consumes when it is fed power and starts up. There is another thing others don't mention. The contactor that is your pressure switch wastes a significant amount of current, even if only for a split second, when it makes the connection, meaning when the switch contact pads engage. That arc from the pressure switch contact pads may not seem like a big deal, but modern utility company electric meters are very good at counting that surge and billing you for it. I was involved in the design of these modern meter marvels.To shorten up what could be a long story, this minutia I am describing might be not different than trying to separate fly poop from ground black pepper, but I think my real answer to this is your proposed selection of pump replacement will probably not change your bill by more than $1 over a one year period. I don't work with Valveman or get anything out of telling you that you should install a cycle stop valve, but I have paperwork that says I know a thing or two about physics. A CSV will save you money in the long run because even the least built pump will not suffer from the frequent on/off that damages ANY electric motor. If you want to conduct an experiment, simply plug in your vacuum cleaner and turn it on and off as much as you can in the course of one hour and then wonder why the cord is hot and the house smells funny. Same idea.

 

[Valveman]

Horsepower is the measure of the energy needed to lift 33,000 pounds of weight, one foot, in one minute. Your large horse was probably able to lift more than that, and the smaller horse less. You may have had 2HP power, or maybe only 1.6HP as you said, depending on how much the two horses combined could lift.

I don't think there is such a thing as a "reputable quality pump" anymore. If all pumps are not made in the same factory in China or Mexico, the parts are. If yo pay someone to put your pump in, they will want to sell you the brand they have and make the most money on. They will probably not even install a pump if you purchase from somewhere else.

But if you DIY, no sense in paying $1,000.00 for the same pump as you can get for 160 bucks on the Internet. They will probably last just as long and if not, you could replace it a half dozen times for the same money as one brand name pump.

 

[2stupid2fixit]

Horsepower is the measure of the energy needed to lift 33,000 pounds of weight, one foot, in one minute. Your large horse was probably able to lift more than that, and the smaller horse less. You may have had 2HP power, or maybe only 1.6HP as you said, depending on how much the two horses combined could lift.

I don't think there is such a thing as a "reputable quality pump" anymore. If all pumps are not made in the same factory in China or Mexico, the parts are. If yo pay someone to put your pump in, they will want to sell you the brand they have and make the most money on. They will probably not even install a pump if you purchase from somewhere else.

But if you DIY, no sense in paying $1,000.00 for the same pump as you can get for 160 bucks on the Internet. They will probably last just as long and if not, you could replace it a half dozen times for the same money as one brand name pump.

Maybe there's a niche market opportunity for me. I wouldn't expect to get rich off of this, but maybe I could turn a profit from a hobby.

Idea: make the most reliable deep well submersible pump money can buy.

One of my clients lets me use their computer system, which includes Windchill engineering software. One can use that to CAD something from a poorly remembered dream into a fully functional, left-handed pickle jar opener.

I wonder how actually difficult it would be to design, prototype and produce a pump that is made of all slow-to-corrode metals like brass and stainless, has things like ceramic bearings, powered by a motor that has the lowest Mean time between failure rate, etc? It wouldn't have to be price competitive. It could be the most expensive pump money can buy, because it would be built to last almost forever. I realize I would not be allowed to call it Kenmore.

oh wait, then i would have to figure out how to get it CSA and NSF approved and UL listed and ASME rated and ah just forget I even came up with the idea. I will just buy another $160 pump built in Guangdong/Shenzhen and be herded like the sheep I am.

The cards are so stacked against Americans wanting to manufacture well-made things here in the USA. I feel like our leadership or lack thereof has bought and sold our futures to line their own pockets, and F everyone else. This goes for both democrats and republicans. The politicians are in this big country club on my dime, but I'm not invited to eat even the whores du ovaries (i dont know how to spell oar dervs) in this club all the dummies like myself are paying for. Roll Tide.

 

[Fitter30]

Hp of a electric motor is a not what it seems. Hp is volts × amps × rated efficiency ÷ 746 watts. If you look at quality motor that has a 1.35 service factor and one that has 1 service factor there are no similarities. Look at motors rated hp on different applications and the amp draws and physical size. Motor are made from cast iron ( industrial ) to stamped steel. Manufacturers play with the numbers the only numbers they don't ( most of the time) is in a industrial application.
Spend 20 minutes on Alibaba ( china version of our Amazon) look up a auto part, tractor or pick a item its interesting.

 

[Valveman]

Maybe there's a niche market opportunity for me. I wouldn't expect to get rich off of this, but maybe I could turn a profit from a hobby.

Idea: make the most reliable deep well submersible pump money can buy.

One of my clients lets me use their computer system, which includes Windchill engineering software. One can use that to CAD something from a poorly remembered dream into a fully functional, left-handed pickle jar opener.

I wonder how actually difficult it would be to design, prototype and produce a pump that is made of all slow-to-corrode metals like brass and stainless, has things like ceramic bearings, powered by a motor that has the lowest Mean time between failure rate, etc? It wouldn't have to be price competitive. It could be the most expensive pump money can buy, because it would be built to last almost forever. I realize I would not be allowed to call it Kenmore.

oh wait, then i would have to figure out how to get it CSA and NSF approved and UL listed and ASME rated and ah just forget I even came up with the idea. I will just buy another $160 pump built in Guangdong/Shenzhen and be herded like the sheep I am.

The cards are so stacked against Americans wanting to manufacture well-made things here in the USA. I feel like our leadership or lack thereof has bought and sold our futures to line their own pockets, and F everyone else. This goes for both democrats and republicans. The politicians are in this big country club on my dime, but I'm not invited to eat even the whores du ovaries (i dont know how to spell oar dervs) in this club all the dummies like myself are paying for. Roll Tide.

It actually wouldn't take much to make a pump that would last. Make the winding and rotor a little longer and put in some good bearings. Might cost an extra 50 bucks per motor to make a good one. But the motor only cost the manufacturer a 100 bucks to make to start with. Adding 50 bucks would be a 150% increase in price, which would make a $500 pump cost $750. People have been conditioned to search for the lowest price, so now cheap products are the only thing available. America stopped looking for quality products so now they are no longer available.

The pump companies just buy each other out so that 12 different pumps are made by the same company and there basically isn't any competition. Let someone purchase all the radio stations and you only hear what they want you to hear.