I would be curious to know the answer to this question also so I hope someone who knows something about the subject answers soon.
Shut the water supply to it and drain it.
Water bladder tanks are tanks which contain a rubber bladder that is filled with either water or air. The majority of water bladder tanks have water-filled bladders. When a water faucet is turned on or a toilet is flushed, the water is piped in from the water tank. As the water pressure and air pressure get low, the contacts on the pressure switch click together. The pressure switch sends an electrical current to the water pump which causes the water pump to kick on and pipe water back into the water bladder tank. The amount of time it takes for the pressure switch to click on depends upon the size of the water bladder tank. The larger the water bladder tank, the longer it will be before the pressure switch starts to deliver electrical current to the water pump. Read more: How Does a Water Bladder Tank Work? | eHow.com http://www.ehow.com/how-does_5001805_water-bladder-tank-work.html#ixzz2A9TeSAnX found this on www.ehow.com
Bladder water tanks contain a rubber bladder from which the water is used. As the water pressure goes down it turns on a switch which causes the water bladder to be refilled from the attached well.
Water bladder tanks are tanks which contain a rubber bladder that is filled with either water or air. The majority of water bladder tanks have water-filled bladders. When a water faucet is turned on or a toilet is flushed, the water is piped in from the water tank. As the water pressure and air pressure get low, the contacts on the pressure switch click together. The pressure switch sends an electrical current to the water pump which causes the water pump to kick on and pipe water back into the water bladder tank. The amount of time it takes for the pressure switch to click on depends upon the size of the water bladder tank. The larger the water bladder tank, the longer it will be before the pressure switch starts to deliver electrical current to the water pump. Read more: How Does a Water Bladder Tank Work? | eHow.com http://www.ehow.com/how-does_5001805_water-bladder-tank-work.html#ixzz2A9TeSAnX found this on www.ehow.com
Mine came new with air pressure in the bladder & no water in the unit so I would assume that you would pressurize the bladder with no water in the unit . Hope this helps .
Water expands when it is heated, this expansion increases the pressure. The bladder tank absorbs the extra pressure, protecting the hot water heater.
Defective bladder / low pressure inside the tank
Install air bladder.
Generally the pressure in the tank air bladder should be 2 psi below the water pressure switch kick in (pump turn on) point. In this example of 48 to 68 Lbs the air bladder pressure should be 46 psi. This pressure should be measured with the tank empty of water, that is to say NO water pressure applied. NEVER over pressurize the air bladder - it would be better to under pressurize if in doubt. Some tank manufacturers may recommend a different PSI differential so check with the tank literature or the manufacturer.
The "bladder" in a bladder water tank is typically made using a durable, puncture resistant fabric that is made to withstand pressure and prevent the pillow from popping.
If the bladder is bad in your expansion tank the tank will fill with water. When this happens the pressure in your furnace will exceed 30lbs and your pressure relief valve will blow off.
You must drain the tank almost to bottom, switch off the pump and water feed to house . Now put in 27-28 psi of air if you have a 30/50 pressure switch. Put in 37-38 if you have a 40/60 switch. It may be necessary to adjust the pressure switch after observing cut in and out.