At a vacation cabin in the mountains , I get water from a nearby spring. At the spring I have a reservoir, and a submersible pump is hung vertically in that reservoir. The system has worked well for many years. The pump is "about" a 1 hp rating, but it could be as big as 1 1/2 hp.
Inside the cabin, I have a pressure tank, and a pressure switch by Pumptrol. My guess is that the tank itself is also a Pumptrol brand, but I do know that it is the bladder type. I don't recall if the pressure tank has ever been replaced or if the bladder has ever been pumped with air. Even if it has, it has been more than 20 years. (We only use this cabin for a total of ten weeks a year, spread over about 4 trips). I drain and winterize the system at the end of the winter trips.
On the very last day of a recent trip, I had some problems in getting enough water and water pressure, and I am trying to get some ideas as to what the problem may be so that when I go back I can properly assess the situation myself and at least be able to help my plumber to troubleshoot the situation.
Here are the symptons and related facts:
1. The pressure control switch is set for 30 psi low to 60 psi high. It also has a "low pressure" pump-safety setting, set at 20 psi. (Again, please note that this system and these settings have worked well for many years).
2. The first thing that I noticed was that the water would cut off once the pressure reached the 20 psi low pressure level. So, I would have to manually reset the switch, and manually hold it to the on position until the pressure reached about 25 psi, at which time the switch would take over and the pump would continue.
3. I can't give exact "time" parameters, but normally I would say that it might take 1-2 minutes for the pressure to go from 30 psi to 60 psi and shut off. But on this last night before we left, it might take 7-8 minutes to go from the low to to high setting. During this "climb", I notice that the gradual rise in pressure was not "even," meaning that it would rise for a bit, and then seem to hesitate at one pressure level for a minute or so, and then take off again and rise at a much quicker rate.
4. The "source" in the resevoir is fine, so we have plenty of water at the source.
5. My pump is wired with 220 v, and I was able to check the voltage at the pressure switch relay, and I have verified that the pump is getting the full 220v, as there is about 110 volts on each side of the wire **going** to the pump.
6. From the brief observations that I could make before I left, I have concluded that I either have a problem with my pump or with the pressure tank. For some reason that I can't quite explain, I have thought more that it might be a problem with the tank, and that perhaps it needs recharging with air. I suppose that I lean toward this conclusion because it seems that my water pressure is erratic as the pump pushes water, and I wonder if this is a sympton of a bladder that has lost its air, and the decreased ability to keep steady pressure on the system.
7. There is some type of plug fitting on the top and the side of the tank, and I know these are the fittings where one must "measure" the air pressure, and refill the unit. I don't know which is which, and I don't know what type of fitting one has to have to make the measurement and the refill if needed. The only type of pump that I have is a bicycle pump, and I assume that I would have to have special equipment for a recharge, or at least have a special fitting.
8. I assume that the pump has a check-valve, but I watched the pressure to see if I was losing water, but it appears that it holds pressure fine (with nothing being used in the cabin of course). From this, I doubt that the check valve is allowing water to escape and limiting pressure buildup.
What is the most likely culprit, the pump or the tank?
Is there an easy way to test the pressure tank ?
Is it hard to recharge the tank with air? What would I need to do this?
Is it very possible that the pump impeller is partially clogged, causing erratic pumping action?
Is it more likely that the pump motor itself is defective, or the impeller, if I do in fact have a pump problem ?
Please make any comments to tell me if I am on the right track, and what I could do for further testing myself to see if I can troubleshoot the problem and possibly even fix it myself. I am not very mechanically inclined, but I do like to know how things like this work, so that I can make minor adjustments and/or at least be able to give good info to my plumber at that location.
Thanks in advance for any help that anyone can give on this !!!