Well pressure tank oddity

Valveman · Oct 1, 2020

the old grind said:
My studying the concept and where/how CSV is used has been that higher the capacity and/or the more water is used the more the system benefits. It's true that with the device a smaller tank is needed, and understand that municipal pumping systems don't use onsite tanks. That does not mean their flow is constant, and they gain from reducing load/NRG-use on the pumps.

If 'simpler is better' it's not hard to appreciate not having any electrical complication, wiring, power trickle. An average guy can plumb one in if he's done any new or rework, eg: sweating copper, taping threads, etc. My tricky bit was to install the gauge some ways away from the pump, in inches. (I moved mine twice) It was a bear to adjust my CSV, but/and with my shallow well pump and paltry water use It's not so easy to quantify the results.

Anyway, my pump will not keep up with the garden hose or the washer. Pressure drop is quite noticeable if/when the tank is drawn down. I'm just waiting for my system to crash to replace it with a deep well and pump, gain flow and pressure. I wouldn't have it without a CSV if for no other reason than pump life. (plenty more)

:2cents:

The CSV doesn't need a very large pressure tank, but will work with any size tank. However, the larger the tank the longer you will be waiting to see the strong constant pressure from the CSV. With an 80 gallon size tank that holds 20 gallons of water, you will be almost 7 minutes into a 3 GPM shower before the tank is drained from 60 down to 40 and the pump is started. As soon as the pump starts the CSV will increase the pressure to a strong constant 55 PSI where it will remain until you stop the shower. If the shower is on for a month, the pump will run continuously for a month, and the pressure will be 55 PSI rock steady for a month. With a CSV and small tank the pump is on and the pressure is constant before you even get the shower temp adjusted and stays that way until you stop the shower or sprinkler.

We used to size pumps as small as possible to limit the cycling, which is why it won't keep up with the hose or washer. You can install as large a pump as you want, and the CSV will make it work like a small pump when small amount of water are being used. Using small amounts of water with a large pump and not having a CSV causes the pump to cycle itself to death. Using a CSV on a larger pump will supply small amounts of water without cycling the pump over and over. Then when larger amounts of water are needed for the hose or washer you have plenty of pump and it will not only keep up, but turn that hose into a fire hose as well.

It is easy to adjust a CSV on a large pump. It is hard to adjust a CSV on a small pump as it is marginal already, and can barely do the job running full out. Not much left to adjust. Thanks a bunch!

GeneV · Oct 1, 2020

2 questions. Do you hear water draining back into the well after the pump shuts off? Do you see standing water around the well, near the inlet going into your house, or anywhere else?

not2old · Oct 1, 2020

It appears that my system had a CSV when I bought the house. I don't remember what the intermittent problems were but I spent more money on service calls with the plumber, telling me that he couldn't find anything wrong, than I have on repairs for the last eight years. I can now trouble shoot and repair the system myself with no waiting a day or two for the plumber. I still have some water when the power goes off unless I'm watering the lawns. I can flush the toilets at least five times and make coffee. The pressure makes the shower much more enjoyable. It's a huge difference showering with 60psi vs 45psi. I got spoiled growing up in a house with no pressure regulator and the city system at 90psi. I recently used my new generator for a power outage that lasted 6 hours. We didn't even bother to turn on the pump. The pressure got low but it never stopped running. It probably helps that only two old people live here. The advice I've received here has made me take notice and learn more about the system. At the moment, I think I will be moving "adding more tank capacity" further up my to do list. I am concerned about the cycling when watering outside or when my open loop geothermal system is running as both use a lot of water. My only fear is having the pump quit during freezing weather as my portable pump can't be left exposed.

Valveman · Oct 2, 2020

not2old said:
It appears that my system had a CSV when I bought the house. I don't remember what the intermittent problems were but I spent more money on service calls with the plumber, telling me that he couldn't find anything wrong, than I have on repairs for the last eight years. I can now trouble shoot and repair the system myself with no waiting a day or two for the plumber. I still have some water when the power goes off unless I'm watering the lawns. I can flush the toilets at least five times and make coffee. The pressure makes the shower much more enjoyable. It's a huge difference showering with 60psi vs 45psi. I got spoiled growing up in a house with no pressure regulator and the city system at 90psi. I recently used my new generator for a power outage that lasted 6 hours. We didn't even bother to turn on the pump. The pressure got low but it never stopped running. It probably helps that only two old people live here. The advice I've received here has made me take notice and learn more about the system. At the moment, I think I will be moving "adding more tank capacity" further up my to do list. I am concerned about the cycling when watering outside or when my open loop geothermal system is running as both use a lot of water. My only fear is having the pump quit during freezing weather as my portable pump can't be left exposed.

I don't quite understand? If you really have a Cycle Stop Valve you won't have to worry about cycling when watering outside, using the heat pump, or anything? Without a CSV you cannot put in enough tanks to keep the pump from cycling when using a heat pump or sprinkler. So, "adding more tank capacity" is not the right thing to do. Making sure you have a Cycle Stop Valve and it is set to work properly is.

You cannot count on a pressure tank having any water when the power goes off. A huge 80 gallon pressure tank only holds 20 gallons of water. For the tank to have 20 gallons stored it would have to be pumped up to 60 PSI before the power goes off. When using a 40/60 pressure switch you can never count on the tank to have water when the power goes off. For every 1 PSI lower than 60 when the power goes off there is 1 gallon less water in the tank. If the pressure is at 41 just before the power goes off, there is only about 1 gallon left in the tank to use. You were lucky it lasted 6 hours with limited use, next time you won't have any luck left.

Big pressure tanks are a thing of the past, and are just a waste of space and money. A 4.5 or 10 gallon size tank is all that is needed with a CSV. These small tanks will cause the pump to cycle for a single toilet flush, but the CSV will keep the pump running and still only cause one cycle if you flush the toilet a hundred times in a row. But even if you flush a toilet only once, and do that 50 times a day, those 50 cycles are not nearly as hard on the pump as the repetitive cycling that happens when running the heat pump or sprinklers for hours. Also, with a CSV, while the heat pump or sprinkler is running, the pump is already on and flushing a toilet does not cause any extra cycles.

The number of cycles a CSV can save when running a heat pump or sprinkler cannot be added back no matter how many times you flush. It is not flushing a toilet a few times a day that causes pumps to be cycled to death prematurely. It is rather the hundreds or thousands of cycles caused by the heat pump and sprinkler that will kill the pump, and you can't put in a big enough tank to stop that from happening. The Cycle Stop Valve stops the cycling, and your generator is the best way to have water when the power is off.

not2old · Oct 8, 2020

Valveman said:
That is one way to get constant pressure, but your pump is cycling itself to death between 65 and 85 while you are getting a steady 60 PSI to the house. A Cycle Stop Valve works like a pressure regulator to deliver a strong constant 60 PSI to the house, but it also keeps the pump from cycling on and off at the same time. A CSV goes before the pressure tank/pressure switch, which if you did that with a pressure regulator would close off and melt down the pump. The fact that you already had to replace the bladder tank means the pump is cycling way too much.

Does a csv act as a check valve or will water flow backwards through it? My hydrants are hooked to the main water line before the pressure tank.

Valveman · Oct 8, 2020

not2old said:
Does a csv act as a check valve or will water flow backwards through it? My hydrants are hooked to the main water line before the pressure tank.

No the CSV does not work as a check valve. Water will go backwards through it. But when you have hydrants in the line before the pressure tank, the CSV needs to go at the well or at least before the first hydrant. Otherwise you have to run those hydrants wide open to use enough water to keep the pump from cycling, because the CSV is not controlling it. The pressure tank/pressure switch and stuff can still be in the house or a long ways from the CSV if needed.

not2old · Oct 11, 2020

I've educated myself a bit and now realize that it was a VFD that I replaced. My system would need to have the csv installed before the pitless adapter as I installed the yard hydrant branch just outside of the well casing, six feet deep. I don't know what size the connection is and don't know if the adjustable valves are able to be installed in the casing. I do want to keep the higher pressures for my hydrants.

Valveman · Oct 12, 2020

not2old said:
I've educated myself a bit and now realize that it was a VFD that I replaced. My system would need to have the csv installed before the pitless adapter as I installed the yard hydrant branch just outside of the well casing, six feet deep. I don't know what size the connection is and don't know if the adjustable valves are able to be installed in the casing. I do want to keep the higher pressures for my hydrants.

Having a VFD would make sense as to why you were having so much trouble. Adding a CSV will solve all those problems. Yes you would need the CSV125 that fits in the well to operate the hydrant that is just outside the well. We make the CSV125 in 60 PSI as the highest pressure and needs a 50/70 pressure switch setting. But we would need to know what size pump you have and the depth to the water in the well to determine if the CSV125 will work with that pump. Probably will, just want to make sure.