13-year-old house with well & septic. A pipe in the incoming water line failed last fall and I made a temporary replacement; time for permanent repair now. While I'm at it, I want to increase water pressure so flushing a toilet doesn't kill flow during a shower.

Well pump cuts in at 40 PSI and cuts out at 50 psi. I know how to adjust these settings. Flushing a toilet causes pump to come on every time. Checking the (about 40" tall, capacity unknown) pressure tank after well cuts out shows that water level is only about 1/3 of tank height -- top 2/3 is air. Do I need a new pressure tank or is this normal?
- If normal, would a bigger tank get me the consistent pressure I want? How do I figure out best tank size? (I do not know well pump rating. How do I find that?)
- If not normal, what should I do about it?

I've got an auxiliary pressure booster (Flotec PressureMate) in the box and ready to install but not sure I should do so with so little water in the pressure tank. Is this concern valid?

Thanks.

13-year-old house with well & septic. A pipe in the incoming water line failed last fall and I made a temporary replacement; time for permanent repair now. While I'm at it, I want to increase water pressure so flushing a toilet doesn't kill flow during a shower.

Well pump cuts in at 40 PSI and cuts out at 50 psi. I know how to adjust these settings. Flushing a toilet causes pump to come on every time. Checking the (about 40" tall, capacity unknown) pressure tank after well cuts out shows that water level is only about 1/3 of tank height -- top 2/3 is air. Do I need a new pressure tank or is this normal?
- If normal, would a bigger tank get me the consistent pressure I want? How do I figure out best tank size? (I do not know well pump rating. How do I find that?)
- If not normal, what should I do about it?

I've got an auxiliary pressure booster (Flotec PressureMate) in the box and ready to install but not sure I should do so with so little water in the pressure tank. Is this concern valid?

Thanks.

For openers increasing the pressure will not increase your volume. It's like turning up the heat on a water heater and expecting to get more hot water. You have to realize the difference between pressure and volume. It's exactly the same as the difference between voltage and amperage. For instance if your pipes were too small you could still have lots of pressure in them, however if you didn't have the volume necessary to back it up you would lose both pressure and volume. Your system must have both to operate efficiently.

(1)Checking the (about 40" tall, capacity unknown) pressure tank after well cuts out shows that water level is only about 1/3 of tank height -- top 2/3 is air. Do I need a new pressure tank or is this normal?

Sounds about right for the top 2/3. Do you have a gauge on the tank and what does it read?
The normal size for a pressure tank is 40 gallons. If you're running out of volume when you flush it might be a little too small for your system. Or your main may be undersized. 3/4" is normal with 1/2" branches supplying not more then three fixtures.

(2)I've got an auxiliary pressure booster (Flotec PressureMate) in the box and ready to install but not sure I should do so with so little water in the pressure tank. Is this concern valid?
Before I installed a 300 buck booster pump I would try a larger pressure tank so you would have more volume to draw from. Good luck, Tom

Thanks Tom.

There is no gauge on my current pressure tank. I got the water pressure readings by watching the system gauge. I can check (and even change) the air pressure in the tank but don't really know what numbers are good ones.

The tank itself (excluding the "riser" on the bottom) is 24" high and about 15" diameter. I think that means it's about 40 gallons -- meaning it will be holding somewhere around 15 to 18 gallons of water.

The main incoming line is 1" and drops down to 3/4" downstream from the pressure tank. Checking branches from the basement (can't get inside walls today): kitchen and one upstairs bathroom are 3/4"; downstairs bathroom is 1/2"; second upstairs bathroom is 3/4" for hot and 1/2" for cold. (Really!)

After reading your response -- and looking at options in Home Depot -- it seems clear to me that I've got two issues:

(1) The 30-50 PSI range on my pump is too low. At the low end almost nothing comes out of the showers upstairs. (At the high end very little comes out of one showerhead -- but I think that's related to how that particular head is plumbed. It's a second showerhead in the "first" upstairs bathroom running off a 1/2" branch from the 3/4" branch to the first showerhead.)

The auxiliary pump would address this issue by boosting pressure by 40 PSI at both ends but dropping it into my current system would raise other issues -- particularly in regard to the capacity of the pressure tank.

Shifting the range on the pressure switch up by 10 lbs (to 40 - 60) is a much easier fix and might be completely effective.

(2) The capacity of my pressure tank is too low to be an effective buffer. Whenever there's any serious demand on the system (like flushing a toilet -- which happens a lot with 5 people in the house) the well pump has to kick in and bring things above the minimum setting.

Adding a larger pressure tank is not too hard -- especially since I have to replace a piece of pipe just "upstream" from the tank.

Since the existing tank seems to be functioning okay, would there be any benefit to keeping it in the system along with the new one? That could give me the effective capacity of a 120 gallon tank at the cost of an 80 gallon tank plus some pipe, labor and floorspace.

Tomorrow morning I'll head out and buy a new tank and the assorted pipe and fittings necessary to install it. Probably will be Friday or (more likely) next week before I actually install it. In the meantime, I'm going to turn up the water pressure to 40 - 60 PSI.

Switch is a Square D -- mounted upside down. Limits posted in the cover are 30 and 50 -- so I won't be tweaking the settings on this switch.

Air pressure in the tank is 44 PSI when the water pressure in the system is at 48 PSI. That's lower than you recommended to zzotto two weeks ago -- but I measured at max pressure. Should I re-check at min?

The switch itself looks pretty shaky. It obviously had water dripping on it for years but now there is nothing above it that could account for that. Lots of rust stains on the inside. Contacts put out a huge spark when closing. I don't like the look of this at all and see no reason to wait for problems.

For anyone reading this thread and looking for results:

Replaced pressure tank and switch with no problems. HUGE improvement.

The old switch was working fine and could have been "cranked up" to the 30-50 range but I didn't like the looks of it after some untold number of years of water dripping on it.

The new tank is 82 gallons -- gives me about 35 gallons of "reserve". It was pressurized to 40 PSI but after two days in my basement it read only 35 PSI. Added pressure to 38 PSI after installing, checking for leaks and draining.

The old tank must have been about 20 gallons. The system was at full pressure when I drained it and the tank only held about 6 gallons of water. Why anyone would install such a small tank in a 4-bedroom, 3-bath house is puzzling; it couldn't have saved that much money. Since I increased both system pressure and tank size at the same time I can't isolate the impacts but I don't think it makes sense to have a 30-50 PSI system in the basement of a 2-story house either.

Anyway, a HUGE improvement in system performance and the work wasn't very hard. Couldn't have managed it without the advice found here -- both in response to my question and to others posted here.

Thanks to all!

Just wanted to say thanks for the update on your water pump. It really helped to give me some ideas on fixing my own energy-sucker :D . Actually, mine is just running non-stop, and can't seem to stabilize at any pressure. I have a few things to try now!

Meghan

Just wanted to say thanks for the update on your water pump. It really helped to give me some ideas on fixing my own energy-sucker :D . Actually, mine is just running non-stop, and can't seem to stabilize at any pressure. I have a few things to try now!

Meghan
Hi Meghan,
If your pump runs non-stop you have, (1) a faulty pressure contreol box, or (2) a leak that won't let the pump achieve cut-off pressure or (3) a faulty check valve on your suction line from the well. To test for a leak. Shut down all the fixtures in the house and turn the pump off. If the pressure gage drops you have a leak. Now turn the pump back on and shut off the valve at the house that's the house shut off, (you're testing the service line from the pump to the house.) Will this allow the pump to pump up to pressure and shut off? If not then shut the pump off and watch for a drop in the pressure gage. If they check out OK take a good hard look at the check valve. Good luck. Tom

Additional follow-up:

When my old water softener broke down last month, I replaced it with one that has a higher flow rate using the Fleck 7000 valve. While I was plumbing in the new softener, I re-installed the original (too small) pressure tank as an auxiliary. The improvements are not huge but they are noticeable and welcome.