Pressure switch extreme short cycling, pressure tank removal questions
#1
01-07-12, 06:44 AM
Pressure switch extreme short cycling, pressure tank removal questions
While at a birthday party for my friends son he complained of low water pressure. I tried to boost the cut out from 45 to 50-55. When I did this his old galvanized tank started to leak where it had previously been welded. He called his dad who said they were planning on removing that tank in the future. So we cut the tank out, and bypassed it.
Problem:
If the spigot under the pressure valve is open all the way the well pump runs flat out like it should. When you close this valve the pressure switch short cycles violently.
Question:
Does there need to be a tank here to fix this problem?
Thanks in advance for any help
Problem:
If the spigot under the pressure valve is open all the way the well pump runs flat out like it should. When you close this valve the pressure switch short cycles violently.
Question:
Does there need to be a tank here to fix this problem?
Thanks in advance for any help
#2
01-07-12, 06:53 AM
Group Moderator
You need to have a pressure tank installed or you will damage your pump. This should be done ASAP.
For more water pressure, get a 40-60 pressure switch. Most pressure tanks are precharged with 38psi for a 40-60 switch. This, of course, can be changed if needed.
For more water pressure, get a 40-60 pressure switch. Most pressure tanks are precharged with 38psi for a 40-60 switch. This, of course, can be changed if needed.
#3
01-07-12, 06:56 AM
Thanks for the quick reply. There is a bladder style tank later in the system, but it seems pretty far away. I have a WellXtrol bladder tank that has been sitting around for a few years. I don't suppose there is much chance of slapping this in, pressurizing the bladder to 28psi, and retaining the 30-50 switch?
#4
01-07-12, 09:46 AM
Super Moderator
No problem installing an old pneumatic tank as long as the bladder is good.
If there is a bladder tank in the system already and the pump is short cycling it must be waterlogged.
If you depress the center of the shrader valve and water comes out the bladder will be damaged and it has to be replaced also.
If some air or nothing comes out of the valve it only needs to have air added.
Pressurize the bladder to 2 psi lower than the cut in pressure.
If you depress the center of the shrader valve and water comes out the bladder will be damaged and it has to be replaced also.
If some air or nothing comes out of the valve it only needs to have air added.
Pressurize the bladder to 2 psi lower than the cut in pressure.
#5
01-07-12, 10:08 AM
I'm on site now. The Bladder tank is a hydo-pneumatic Meyers. I noticed when I got here that it's shut off valve was off. It was holding about 28psi when I checked it. I opened the valve and tried to run the well pump. It's still short cycling. This tank only has one pipe connected to it. I thought my WellxTroll had an in and out. Is this not a bladder tank?
#6
01-07-12, 10:32 AM
Group Moderator
A pressure tank only has to be some place on the system but is most cases where the switch is. The tank only has one pipe to it. It is both an in and out.
Be sure to check the other tank with water pressure at 0 psi.
I wonder why the valve on the old tank was closed
Be sure to check the other tank with water pressure at 0 psi.
I wonder why the valve on the old tank was closed
#7
01-07-12, 10:55 AM
The pressure tank was presumably turned off when they put in a new boiler, and forgot to be turned back on. A call to the home owner verified that the tank should still be in use. Maybe the old galvanized tank was making up for the pressure tank being turned off. I've messed with the pressure switch so much, I have no idea where to even begin. What a nightmare.
With the water pressure at zero, the pressure tank has 28psi in it. No water came out when I drained, and re pressurized the tank. I have tried to lower the pressure valve just to get it to hold low pressure without short cycling, but I can't get it to not short cycle like crazy.
I guess I am about out of options. Since the plumbing was drained would all the lines being filled with air cause a problem?
With the water pressure at zero, the pressure tank has 28psi in it. No water came out when I drained, and re pressurized the tank. I have tried to lower the pressure valve just to get it to hold low pressure without short cycling, but I can't get it to not short cycle like crazy.
I guess I am about out of options. Since the plumbing was drained would all the lines being filled with air cause a problem?
#9
01-07-12, 11:10 AM
Group Moderator
Dumb question time: Are you sure that the pressure tank is for the water system (Hot/cold for washing/bathing) and not the heating/boiler system? Pressure tanks are found on boilers as well. The boiler system and the water system should not be connected together. (I think 
)
Do you have a pressure gauge on the water system? If not, maybe you should install one so you know where you stand. They are only about $6.
Pressure switches do not have a lot of adjustment. IE: It would be tough to get a 30-50psi switch to act like a 40-60psi switch.
Air in the lines would not cause a problem as the air would compress, similar to a bladder tank.
Before things get too mixed up it might be a good idea to step back and start at square one and put in your spare tank you have in place of the old galvanized tank.
)Do you have a pressure gauge on the water system? If not, maybe you should install one so you know where you stand. They are only about $6.
Pressure switches do not have a lot of adjustment. IE: It would be tough to get a 30-50psi switch to act like a 40-60psi switch.
Air in the lines would not cause a problem as the air would compress, similar to a bladder tank.
Before things get too mixed up it might be a good idea to step back and start at square one and put in your spare tank you have in place of the old galvanized tank.
#10
01-07-12, 11:13 AM
Group Moderator
The current bladder tank is mounted horozontally between the floor joists. Would that matter?
#11
01-07-12, 11:15 AM
The boiler has it's own expansion tank, and a cold line attacted, I assume, to auto fill the boiler as neccasary. There is a pressure gauge on the water system right next to the pressure switch. If I run the pump with th spigot open I can build the pressure up to where the contacts close at around 30 psi as I think would be normal. Adjusting from here has no reall effect. There is no way to empty the pressure tank without fully removing it.
#12
01-07-12, 11:18 AM
Group Moderator
To drain the water system (hot/cold) Turn off the well, or close the valve, and open a faucet. All the pressure will then drain out. Then you can check pressure of the tank. No disconnection of the tank is needed.
#13
01-07-12, 12:00 PM
The current bladder tank hooks to a line marked "Boiler make up water" Then tees off directly to the bathroom plumbing. I ran the water down to zero via the spigot, and applied the correct 28psi to the bladder tank, then tried to run the well pump. Still short cycling.
My only 3 options I see now are
1. Remove the current bladder tank, empty it, and mount it on the floor next to the pressure switch
2. Install my WellxTroll
3. Replace the pressure switch.
The pressure switch contacts don't look the greatest, but the system was working correctly before the leak.
I think from now on I will stick to my electrical tool belt, and forgo any type of plumbing that is not mine.
My only 3 options I see now are
1. Remove the current bladder tank, empty it, and mount it on the floor next to the pressure switch
2. Install my WellxTroll
3. Replace the pressure switch.
The pressure switch contacts don't look the greatest, but the system was working correctly before the leak.
I think from now on I will stick to my electrical tool belt, and forgo any type of plumbing that is not mine.
#14
01-07-12, 12:31 PM
Super Moderator
Things just don't sound right.
It would be helpful if you could take several pictures so we could see what you do.
You can upload photos to a free site like Photo Bucket and either provide a link or use the button above the reply box to have them appear in your post.
It would be helpful if you could take several pictures so we could see what you do.
You can upload photos to a free site like Photo Bucket and either provide a link or use the button above the reply box to have them appear in your post.
#15
01-07-12, 12:46 PM
Of course, I forgot my camera. I will try and get some pics, but I am thinking it is probably time to call in a real plumber. The boiler makes me nervous, the last thing I'd want is to damage it.
#17
01-07-12, 02:17 PM
Group Moderator
My vote is #2. Install the Wellxtroll where the old galvanized tank was. Leave the other tank in the joists alone. The system was not short cycling when the galvanized tank was in place. Just low pressure which then sprung a leak. It was on its way out anyway.
#18
01-08-12, 05:57 AM
I may have caught a break, my WellxTroll has a spigot, and I can adapt it to hook into a spigot right by the current pressure switch. Theoretically I can just connect them with a piece of hose, turn off the ball valve to the other pressure tank, and give it a go. I can also power the well with the pressure switch from mine, which was working fine before the city water came through. If he wants to skip the plumber and try this, I will get pics of everything.
#20
01-11-12, 09:44 AM
A tank of any kind can be temporarily installed where the galvanized tank with the leak used to be. The tank needs to be above the pipe to which it is attached. You will need some way of adding air to it.
With the pump off, make sure the tank is empty of water, then close off all openings except to the water pipe down below. Then turn on the pump. After the pump shuts off, measure the pressure and then add 20 more pounds of pressure to the tank. After a few pump cycles these added 20 pounds will disappear but don't add them again.
If the temporary tank does not have a bladder, it may need to be recalibrated perhaps every month (empty it and repressurize and add the extra 20 pounds once).
When you get a proper pressure tank with bladder, install that and follow its instructions for setting the pressure.
The make up water tank above the furnace cannot double as a well water system pressure tank because there is a check valve in the cold water inlet before the tank to maintain the correct boiler pressure.
With the pump off, make sure the tank is empty of water, then close off all openings except to the water pipe down below. Then turn on the pump. After the pump shuts off, measure the pressure and then add 20 more pounds of pressure to the tank. After a few pump cycles these added 20 pounds will disappear but don't add them again.
If the temporary tank does not have a bladder, it may need to be recalibrated perhaps every month (empty it and repressurize and add the extra 20 pounds once).
When you get a proper pressure tank with bladder, install that and follow its instructions for setting the pressure.
The make up water tank above the furnace cannot double as a well water system pressure tank because there is a check valve in the cold water inlet before the tank to maintain the correct boiler pressure.
#21
01-11-12, 03:49 PM
Super Moderator
I have heard arguments for adding air to an already pressurized system but it is not a generally accepted method.
All manufacturers of pneumatic tanks have pretty much the same procedure which is to first unplug the pump and open a tap.
Then add air to the pneumatic tank to a pressure of between 2 and 4 psi below the pump cut in pressure.
If the tank is waterlogged you need to allow the water to stop running out of the tank.
This method works for both bladder and non bladder tanks and can also be used short term if a bladder tank has ruptured.
All manufacturers of pneumatic tanks have pretty much the same procedure which is to first unplug the pump and open a tap.
Then add air to the pneumatic tank to a pressure of between 2 and 4 psi below the pump cut in pressure.
If the tank is waterlogged you need to allow the water to stop running out of the tank.
This method works for both bladder and non bladder tanks and can also be used short term if a bladder tank has ruptured.
#22
01-11-12, 09:52 PM
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#23
01-12-12, 08:00 AM
If the pressure tank is some distance away then pressure differences while the pump is running can cause a turn off switch much closer to the pump to turn off the pump before much water has entered the tank. The system pressure than settles down (equalizes) quite close to the turn on pressure. Then the pump cycles on again after only a small amount of water has been drawn.
Provided you have some headroom between maximum safe pump pressure and desired pump cut off pressure you can have one turn off switch near the pump set almost at the first pressure and another turn off switch at the far away pressure tank set to the second pressure. This will allow more water to enter the tank before the pump shuts off, and longer times between pump starts.
The purpose of adding more air later is to enlarge the air cushion in the pressure tank. This is an unscientific method but improves performance if you were unable to pressurize the system after emptying out the pressure tank and before turning the pump back on. If you add more air, the system pressure soon settles back to the original turn on and turn off pressures.
Provided you have some headroom between maximum safe pump pressure and desired pump cut off pressure you can have one turn off switch near the pump set almost at the first pressure and another turn off switch at the far away pressure tank set to the second pressure. This will allow more water to enter the tank before the pump shuts off, and longer times between pump starts.
The purpose of adding more air later is to enlarge the air cushion in the pressure tank. This is an unscientific method but improves performance if you were unable to pressurize the system after emptying out the pressure tank and before turning the pump back on. If you add more air, the system pressure soon settles back to the original turn on and turn off pressures.
