Well pump problem... foot valve or blader tank?
I've been reading old posts here for the last couple of weeks, and I think you all ahve helped me solve my problem. Before I go spend a couple hundred dolars I'd like to check my work with you if you don't mind. I have a 27-year-old drilled well. My neighbor thinks it goes down about 75 feet, but I don't know. The water level is less than 8 feet from the ground. In my basement there is a 10-year-old Sta-Rite/Con-Aire 19 gal(?) bladder tank with a shallow well pump on top. The pump used to be a 5/8hp at 30/50 or 40/60, but two or three years ago it died and I replaced it with a 1hp Craftsman pump with a 40/60 switch running closer to 44/78. I've always called it a jet pump but there is only one line going from the well to the pump so I think this is techically incorrect. A few weeks ago we started having intermittent water supply problems, including a slapping sound in the pump as it came on and tried to get water moving (this is cavitation?). Air came out of our faucets along with sediment (looked like rust) in the water. A well contractor suggested (over the phone) changing the foot valve due to age and because it's a common cause of cavitation problems. I told him the well side of the pump had water (there is a check cp near the pump intake) but he said it doesn't take much and suggested that even though I couldn't see any loss of prime, there could be a slow foot valve leak... I am willing to change the foot valve, but if I have to I'll have some questions first. Before going there, however, I checked the pump prime (OK), drained and precharged the tank (it was in the mid-20s so I added nearly 20psi to get close to my 44psi cut-in), reconfirmed there was water in the supply line (there has been water there all along). After that nothing changed, so I drained and re-primed the pump and poured water into the line from the well both inside the house and out at the well head (through the vent -- is that OK?), just to be sure. Still no change. At this point I feel that I've ruled out any but the slowest foot valve leak and the pump is not losing its prime. However, I noticed that after draining and recharging the bladder tank things got worse, especially the slapping sound when the pump comes on. The pump bucks and jumps, and the pressure gauge just waves back and forth between 40 and 60 or so while the pump runs continuously. If a tub faucet is running the whole system can lose pressure and the pump does not seem to be able to recover. It ends up around 20psi at the pump and the plumbing pipes deliver a trickle if anything. If I shut the pump down and close the valve between the system and the bladder tank, the pump can re-pressurize the plumbing pipes as if everything were normal. Today, from a fresh start, if I close the valve leading to the air/water tank, effectively eliminating it from the system, everything seems to work fine. The pump comes on and runs continuously when we use water, but it does not have the slapping problem and it is able to move enough water to keep up with the demand. The pressure gauge hangs around 75psi while the water is running and settles in the mid- or upper-60s after we turn the water off. If I open the valve to the bladder tank -- slightly -- I can hear it filling with water, and the pump is able to fill it as long as I keep the flow rate low. Then we can run tap or tub water and delivery is smooth until we get down to the pump's cut-in pressure. At that point if I've left that valve open the pump will slap and buck when it starts up again, and we are back where we started. Does this make sense? Right now I have left it set up with the valve closed and the system works fine -- the pump is just running more than one would like, and there is some surging at the faucets when it kicks on. But as long as the bladder tank is cut off from the pump and plumbing system, everything seems to work OK. Is it time to replace this tank? Is the same tank OK (around $150, I think)? Sorry about the long post, and thanks in advance for any replies. at least 75% of what I've done so far has been based on ideas from this site. I can't thank you all enough. There is no way I could afford to have someone come in and take care of this for me. You have a shallow well jet pump. If there is 2 lines from well to pump it is a deep well jet pump. The first thing I would do is replace the pressure gauge, or at least connect another one to a nearby hose bibb, and confirm your pressure. I don't believe a Sears jet pump will have the capabilities to reach 78 psi. Once I ascertained the pressure range that the pump is operating at, I would set the tank precharge at 2 psi less than pump cutin pressure. This is done by turning off power to the pump and completely draining the tank. If the tank won't drain completely, or water comes out of the air valve, the tank is probably bad. Ron No water comes out of the Schrader valve on the tank, and the tank does seem to drain completely. I will pick up a new pressure gauge on my way home today and hold off on the tank for now. If it matters: when the system is fully charged the Schrader valve on the tank reads roughly 10psi less than the pressure gauge on the pump. The pressure you see at the Schraeder valve is probably a truer reading than the gauge. Not all pressure measuring devices are accurate, but there shouldn't be more than a couple of pounds difference between the tank and the gauge. Ron I picked up a new pressure gauge and put it on the pump. The tank readings were indeed accurate, and my pump gauge was off by at least 10psi. As a result the pump was set to kick on closer to 30psi than 44, which was actually much lower than the air precharge in the tank. I drained the tank, set the precharge at 38psi, and adjusted the pressure switch to cut in at 40 and out at 63-64. Now the system seems to work OK with the tank included, but I'm guessing there is still some air in the works, as the pump sometimes misses when engaging or even while pumping. Not constantly -- maybe once every other cycle -- just enough to tell me I'm not finished. If I shut the power off and then back on it tends to engage just fine. What should my next step be? I assume I haven't solved the original problem yet since the whole system ran fine for three years up until a few weeks ago -- something introduced air into the lines, but what? One other thing I've noticed is that after the pump shuts off around 63psi the gauge reading settles back to 59-60 slowly. This takes maybe 20-30 seconds. Is that just a function of the water in the house pipes farther from the pump finding its level/achieving equilibrium? After getting the tank precharge and the pressure switch settings straightened out yesterday, I replaced the foot valve in my well this afternoon. Everything is working perfectly. Thanks for the help. Glad it's all straightened out. Check the precharge every few months to keep it working well. Ron
Related Posts:
Weilmclain indirect water heater safety valve
Weil-McLain indirect water heater safety valveWe have a Weil-McLain indirect water heater which takes the hot water from our boiler at 180 degrees and circulates it around a tank with the domestic...
Sewage sump pump and tank maintenance cleaning
Sewage Sump Pump and Tank Maintenance, CleaningI just joined this forum and thought I would say Hello to everyone by asking a question...hopefully one that hasn't yet been asked (I looked but coul...
Wellxtrol pressure tank
Well-X-Trol pressure tankI have a basic question about my 20 (appears to be 20 gal, most of the nameplate data is unreadable) gal pressure tank.It is blue and there are large Goulds Pump and Well-...
Well pump problems
Well pump problemsHey Old Guy where you at? Thought I would pick you brain abit. I went to look at a friends electrical problem and since I was able to correct that he decided to see what I could...
Submersible pump misbehaving pressure switch and pressure gauge
submersible pump: misbehaving pressure switch and pressure gaugeI have a submersible pump in a domestic well and use a Square-D 40-60 pressure switch. I drained the tank and then installed a new s...
