Well Water System - How To Check Pressure Tank?

Spencer · Apr 20, 2003

I have had what I consider to be high electrical bills ever since I moved to this house it the fall of 2001. We have all of the same appliances and electronic equipment that we had in our previous house. The only difference between the two houses is that this house has a well pump (actually two, one is for sprinkling) and our other house was in the city so we had city water. This house is newer and better windows and insulation. I recently heard that if your pressure tank (bladder tank?) is malfunctioning then your well can run more often that it should and that can cause high electrical bills. So how can I check to make sure my system is working optimally? The sellers had to have a new well put in because their existing well did not meet county health standards. So everything in the system is new except for the pressure tank, they reused the old one.

By the way I am paying the exact same rates per kilowatt hour as I did in the old house. My bills in the old house we generally $40 to $60 a month. The bills in the new house are $80 to $100. Should pumping my own water cost me $40 per month?

BigDave · Apr 20, 2003

Spencer...again, /forums/images/graemlins/wink.gif

I have a well, and can hear my check valve shut when the pump turns off...it's in the corner of my basement right under my recliner in the family room, so I hear it close a couple of times when the misses is doing laundry. Ooops, did I just say I'm sitting in the recliner while the misses is doing laundry...I meant to say I could hear the valve while I am working in the basement. /forums/images/graemlins/grin.gif

I would propose a test. Turn off the electric to the pump, and then check to see if you have normal water pressure, I would think you should be able to drain a few gallons from any faucet before there would be any perceivable drop in pressure.

So what can be wrong? Broken bladder, bad pressure switch, stuck-open check valve. Maybe a fellow TBNer is a plumber by trade or hobby, because I'm not sure how to solve which one it would be.

Anonymous Poster · Apr 21, 2003

My pool circulating pump is about the same HP as my well pump. I run the pool pump 6-10 hours per day depending on the season, and estimate it costs about $30/month for electricity. I don't have a clue what my cost per kw hour is; it is what it is and I can't do anything about it, so I never looked. But, I know it's no bargain. I've had bladders, relays and just about everything else go bad on the well system. You know the bladder is bad when the well comes on immediately as soon as you turn on the water - the bladder should hold some reserve. A bad relay continually clicks on and off - it won't hold in the "on" status.

Check with your local electric service provider - Florida Power & Light will send a techie to the house to check for unusual power draws and such, no charge.

JATO_RaT · Apr 21, 2003

Spencer, checking your pressure tank is simple and should be done at least once a year. Your electric usage is very unlikely to be related to the tank. The amount of water you use, the depth of your well can be factors though. If your running a second pump for irrigation, that is most likely the source of the biggest increase since you will be running it for extended periods. Folks with pools run pumps from 4 to 6 hours a day and will increase electric bill cost by as much as $150 a month.

To check your tank you need to have a air gauge, the more accurate, the better. On your tank is a cap covering (and sealing) a schrader valve just like your car tire has. Before you get a accurate reading you need to establish what your cut-in pressure is. Do this by being near the pressure relay, an adjustable device that senses pressure and turns on/off the pump. You will have to open a faucet somewhere to get the system to cut-in. Lets say you find the cut-in pressure to be 40 psi or the pressure that the system has to drop to before the pressure switch turns on the pump. At that point, turn off the electrical to the pump, ususally right on the pressure switch. Allow all the remaining water pressure to run out to zero PSI. Check the tank pressure, it should be about 3 lbs less then the cut-in pressure or about 37 to 38 PSI and no more then 40 PSI. This is called your precharge pressure. If its low, pump it up, this is best done with an air compressor as it can take quite a bit of air. Be sure to recap the schrader valve. Doing this simple procedure will increase the life of your bladder/tank and also keeps the pump from cycling as frequently. Rat...

Mike_Dumond · Apr 21, 2003

What RaT said is pretty good advice. Only other thing I would suggest, is to let a bit of air out of the schraeder valve before you do anything. If you get some water coming out, you got a bad bladder. If not, then check the bladder pressure. Make sure the tank is completely out of water first. Any water left in, will skew the working pressure. There should be a drain at the bottom of your set-up. Keep it open when you check and especially when you recharge the bladder. If it's bad and you didn't get air in the first step, you will hear air coming out at this point.

WVBill · Apr 21, 2003

Spencer: I'll add another test to the one Rat described. This one you can do from your recliner like BigDave. /forums/images/graemlins/wink.gif

Open a faucet or turn on the shower and then listen for the on-off click of your pressure switch. If everything is working right (well tank is in good shape, the right size, properly pressurized, pump is the right size and working, etc.) the pump should cycle on for at least two minutes before cycling off.

The life of a well pump is measured in how many times it turns on not in how long it runs. The reason for the pressure tank is to keep the pump from coming on every time you get a glass of water or wash you hands. The pressure tank stores about 5 - 10 gallons of water that is used for these small draws.

As Rat pointed out, the cut-in pressure is usually 40 pounds (sometimes it is 30). The cut-off pressure is usually 20 pounds above cut-in.

The pump you have for sprinkling may be set up to run continuously any time you have an outdoor faucet on. If you do alot of sprinkling, I'd suspect that system as being the bigger contributor to your higher electric bills.

Either way, figure out how many kilowatt hours you get for $40 (like 500 kwh if you're paying 8 cents per kwh) then divide by the wattage rating of the pump(s) (yes, startup watts will be momentarily higher than running watts) to see how long those pumps would have to run to cost $40.

riptides · Apr 21, 2003

RaT,

( Folks with pools run pumps from 4 to 6 hours a day and will increase electric bill cost by as much as $150 a month. )

In Central VA, we run our pool pump 8-12 hours a day and I don't think it is half that. Course you did say as much as. And I think that is a key, Spencer should look at.

Spencer,
I think, IMHO, that perhaps your motors in the appliances, and well pump itself, may need rating checks. Perhaps your not comparing apples to apples. I am thinking about your well pumps, in the wells themselves, and your furnance system, specifically.

-Mike Z. /forums/images/graemlins/laugh.gif

Anonymous Poster · Apr 21, 2003

(
Either way, figure out how many kilowatt hours you get for $40 (like 500 kwh if you're paying 8 cents per kwh) then divide by the wattage rating of the pump(s) (yes, startup watts will be momentarily higher than running watts) to see how long those pumps would have to run to cost $40. )

Unless I totally screwed up my math (which is always a possibility), my pool pump costs me about $10 /month. The pool pump is a 1/2 horsepower motor, which converts to 372.8 watts. Where I get screwed up is including the time factor. Are watts always considered to be watt hours? I'll assume so and continue on as if it's true /forums/images/graemlins/wink.gif . Anyway, the watts come to .3728 kilowatts. Run 10 hours a day, thats 3.728 kilowatts per day, or a little less than 112 Kw per 30 day month. This thread motivated me to check, and my kilowatt charges are approximately $0.083 per Kwh. 112 @ $0.083 = less than $10. Double it for a 1 HP motor.

The $30 I mentioned above was a guess based on observed electric bills when the pump only ran part of the month. Certainly it's no more than that, because my total electric bill runs less than $100/month unless the A/C is running all the time.

cowboydoc · Apr 21, 2003

Yea but Rat lives in Ca. In CA you are going to see rates from 2 - 10 times what some of you are paying.

WVBill · Apr 22, 2003

( Are watts always considered to be watt hours?... Anyway, the watts come to .3728 kilowatts. Run 10 hours a day, thats 3.728 kilowatts per day, or a little less than 112 Kw per 30 day month. )

You've got the math right.
1 KiloWatt drawn for 1 hour = 1 KiloWattHour (kwH). So .3728 kilowatts. Run 10 hours a day, thats 3.728 kilowatthours per day, or a little less than 112 kwH per 30 day month.