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Hannesnel
May 29, 2008, 10:32 AM
Were can the pressure go in a booster pump tank. The bladder is not punchered

jlisenbe
May 29, 2008, 12:58 PM
NOt sure what you mean. Are you saying the booster pump is pumping but you have no pressure? If so, then how do you know the bladder is not punctured?

Hannesnel
May 30, 2008, 08:26 AM
NOt sure what you mean. Are you saying the booster pump is pumping but you have no pressure? If so, then how do you know the bladder is not punctured?

The boosterpump is working fine. The air around the bladder must be 2 bar. When you fill it with air 2 days later all the air is out. And if the bladder was punctured then there shoud be water around the bladder and there are not!

jlisenbe
May 30, 2008, 05:18 PM
You are correct in saying that a ruptured bladder would allow water above the bladder. The normal way of checking for that is to depress the air valve at the top and see if water comes out. I assume it is not coming out. That would only seem to leave one possibility... the air valve at the top of the bladder tank has a slow leak. Have you checked for that?

Hannesnel
Jun 1, 2008, 09:31 AM
You are correct in saying that a ruptured bladder would allow water above the bladder. The normal way of checking for that is to depress the air valve at the top and see if water comes out. I assume it is not coming out. That would only seem to leave one possibility...the air valve at the top of the bladder tank has a slow leak. Have you checked for that?

I pressured it with aircon gas and then I test if with a gas leaktester but it's not leaking there. I have no idee what the problems is.

jlisenbe
Jun 1, 2008, 11:33 AM
How large is the tank and how old is the tank? I'm assuming this is a vertical tank with water entering and exiting through one opening at the bottom.

Even if the bladder is ruptured, the tank would still hold pressure for several weeks until the air was dissolved into the water. So, I would think the only place for the air to go would be through some leak in the tank.

Hannesnel
Jun 3, 2008, 10:24 AM
How large is the tank and how old is the tank? I'm assuming this is a vertical tank with water entering and exiting through one opening at the bottom.

Even if the bladder is ruptured, the tank would still hold pressure for several weeks until the air was dissolved into the water. So, I would think the only place for the air to go would be through some leak in the tank.

It is two 50L Tank and the system is now in for 8 months. I did put the hole tank in water as you do with a tyre but can't fined any leak. On the same farm but 1km away it's the same problem with a other tank. I did park the valve on top with paint may be somebody is bothering there.

jlisenbe
Jun 4, 2008, 10:14 PM
Hann, I found this advice on another site. It refers to the bladder becoming stuck to what sounds like the top of the tank. See for yourself:

1. Too little air in the pressure tank: Unless you live in a climate where there is never condensation on the exterior of the water tank, normally the (lower) portion of the tank that contains water will be cooler than the upper tank, causing the condensation of water onto the tank surface. If the condensate line is high on the water tank this means it's filling up with water and there is not enough air charge. (Air resides at the top of the pressure tank and water in the tank bottom.) (Water Tanks in Dry Climates: if you live in an arid climate like Arizona in the U.S. or San Miguel de Allende in Mexico you may not ever see condensation on the water tank regardless of other factors.)

2. Not enough water in the pressure tank: If your water pressure tank never shows any condensation, perhaps that's because no water or not enough water is entering the water pressure tank. This is the opposite problem from a water tank that has lost its air charge. We've found this uncommon case (of no water in the water tank) when the tank was defective, the pipe into the tank was clogged, or the tank was overcharged with too much air pressure. If there is too much air in the water pressure tank, this problem is usually self-correcting - the excess air leaves the tank through the supply piping to the building. But if the entry to the tank is blocked, or if the water-containing rubber bladder in a "captive air" water tank is defective (it can become stuck to itself and remain collapsed), the result can be a rapid on-off short cycling of the water pump. I test water pressure tanks to see if they're empty or nearly empty of water by seeing if I can rock or move the tank. If the tank is heavy with water it does not move easily. Be careful not to jiggle and break a pipe.

I found this on this site: How to diagnose lost air in a building water pressure tank - private pump and well system do-it-yourself repairs (http://www.inspect-ny.com/water/WaterTankAirLoss.htm)