Well Tank / Water Tank Air or Leak Repairs

Water Pressure Tank / Water Tank Diagnosis & Repair for Air Charge, Water Tank Leaks, Rust, Corrosion, Sweating

Steel Water Tank Rust Perforation & Emergency Tank Repairs

If the pressure tank has a pinhole leak can it be repaired?

Possibly, yes, depending on the extent of rust and on the outcome of discovering during repair just how much hidden rust is on the inside of the water pressure tank.

At your local hardware store you can probably purchase a special screw and washer part (less than $5.00. U.S.) intended to temporarily fix pinholes in water pressure tanks.

Watch out though: often a pinhole on the exterior wall of the tank will be found to be a bigger hole when you start messing with it - because the tank is corroding from the inside (usually) the area of thin walled steel may be bigger than you think.

Buy several repair screws of varying size and start with a small one to see if that can screw in tightly enough to stop the leak. If it won't, you'll need to use a larger screw.

Welding is technically possible but not economical, and a repair epoxy might work with good surface cleaning provided you could take the tank out of service long enough and keep it dry during the gluing process, but like the little Dutch boy with a finger in the surface of the dike, that's not the most reliable repair.

Figure a new water tank is in your future.

Emergency temporary repairs to a leaky Water Tank

If the rust perforation on a steel, bladderless water pressure tank is very tiny, 1/8" or so, temporary repair can sometimes be made using a special short lag-type threaded screw with a neoprene washer. Leak repair screws are sold for this use.

In an emergency you can even fabricate one of these water tank leak repair lag bolts, as we did for our photo (left).

We used a 3/4" long lag screw and a thick neoprene washer that happened to be around. If you buy a factory-made version of this device the washer is designed to seat and seal against the curved surface of the leaky water tank.

Watch out: because the steel will be thin around the rust spot, you may find that you need a larger screw than you thought, or bought.

We recommend buying several sizes of water tank repair screws, but start by using the smallest one that will be secure when screwed all the way in to the tank.

Below we show an assortment of typical plugs used to make a temporary patch on a leaky water tank.

The left-most tank repair or patch device is intended for larger holes. The "tee" screw is inserted into the hole and then the assembly tightened by the top bolt. The three middle lag-screw type plugs are simply screwed into smaller rust or other perforations in the water tank. Start with the smaller screw and if you can screw it up tight to stop the leak, quit there.

If however you cannot screw the plug tightly to the tank surface, remove it and move to the next larger plug screw size.

The right-most expansion plug is not intended for tank leak repairs; rather it is an expanding pipe plug that can be used when pressure testing water or other piping.

In our OPINION such repairs are temporary at best and you need to beware that the repair spot may leak again soon.

Just blob on some sealant to stop a leaky water tank?

A second type of water pressure tank repair that might work in some locations is the use of quick-setting epoxies, caulks, sealants, including those that can work in wet conditions.

Details are at CAULKS, NONTOXIC

You still need to replace the water tank but this approach can stop or slow a leak while you wait for the new tank to be installed.

This approach would not work on the horribly rusted water tank shown above - that one is just too far gone.

Water Tank Leaks Leak Water Out or Air Out, depending on the Leak Location

Leaks like the ones in the above photos can also leak the air charge out of the upper portion of the tank when the in-tank water level is below the leak point. A water pump short cycling problem could be due to an air loss in the tank to a leak in the tank itself.

Example of a water pressure tank beyond repair

This steel water storage tank is leaking. When you see damage like this on a water tank, the perforation has rusted through from inside the tank. A tank that looks like this needs to be replaced.

Watch out: don't poke at rust like this on a water tank - you are likely to change a slow seep or drip into an immediate catastrophe - the steel around the site of rust perforation is usually quite thin.

Do I Need a New Water Tank? - should I replace my old water tank?

We just had our pump replaced after 18 years. Total cost with tax was $2400. Project was done on emergency basis on a Friday night and we were really stuck. During his visit the plumber/owner suggested we consider a larger pressure tank than our 20 gallon unit, also recently replaced.

The system worked well for many years and I don't see the need to purchase another larger tank. Any thoughts? - Wayne Ouellette

Reply: You may not need a new water pressure tank.

If your water tank is a newer bladder type, even a smaller 20-gallon tank gives the equivalent of a larger old style (non-bladder) tank in the draw-down cycle - the amount of time that you can run the water before the pump has to come on.

As long as your pump is not WATER PUMP SHORT CYCLING (which may shorten pump life), the gain from a larger tank is probably not much. If your tank is an older type with no internal bladder, the reason to go to a newer tank would be reliability and reduced maintenance.

Some Reasons to Consider a New Water Tank

1. Leaks:
   
   The water tank is perforated, damaged, or leaking - you need a new one
2. Bladderless water tank:
   
   The water pump has
   
   constant WATER PUMP SHORT CYCLING problems
   
   and the water tank is an older non-bladder type you can reduce the frequency of water tank maintenance (adding air) and eliminate problems with automatic air volume controls that try to add air for you by installing a new bladder type water pressure tank.
   
   At WATER TANK TYPES: WATER, OIL, EXPANSION, ALL we explain the different types of water tanks.
   
3. Limited well water:
   
   Your well has a poor flow rate and you often run out of water.
   
   Less costly than drilling a new well is the addition of greater water storage capacity in one or a series of larger water tanks.
   
   But first see WATER PRESSURE LOSS DIAGNOSIS & REPAIR, and
   
   see WATER PRESSURE PUMP REPAIR GUIDE.

Watch out: before you go to the trouble and expense of replacing a water pressure tank, make sure that you have correctly diagnosed the problem that you are "curing" - you wouldn't want to replace a water tank only to find that you still have the water pressure or quantity problem because another, perhaps less costly, part was at fault.

Also

see WATER TANK LIFE & REPLACEMENT.

The illustration at page top is courtesy of Carson Dunlop Associates, Inc. in Toronto.

Check other water pump and pressure problems before replacing expensive parts - Before assuming that a water problem is due to the pump or well itself,

see WATER PUMP REPAIR GUIDE a specific case which offers an example of diagnosis of loss of water pressure, loss of water, and analyzes the actual repair cost.