A.O. Smith BTI-80 warranty Tank Cleanout Procedure, FLO-JUG Method of Deliming

TANK CLEANOUT PROCEDURE

The following practices will ensure longer life and enable the unit to operate at its designed efficiency:

1.Once a month the heater should be flushed. Open the drain valve and allow two gallons of water to drain from the heater. Inlet water valve should remain open to maintain pressure in tank.

2.A cleanout opening is provided for periodic cleaning of the tank. Gas must be shut off and heater drained before opening cleanout.

To clean heater through cleanout opening, proceed as follows:

1.Drain heater.

2.Remove outer cover plate from lower side of heater jacket.

3.Remove six (6) hex head screws securing tank cleanout plate and remove plate.

4.Remove lime, scale, or sediment using care not to damage the glass lining.

5.Inspect cleanout plate gasket, if new gasket is required, replace with A. O. Smith part no. 99038.

6.Install cleanout plate. Be sure to draw plate up tight by tightening screws securely.

7.Replace outer jacket cover plate.

In some water areas the sediment might not be removed by this method and may result in the water heater making rumbling or boiling noises. To dissolve and remove these more stubborn mineral deposits, A. O. Smith UN•LIME Professional Delimer should be used.

Figure 9 illustrates most of the following steps.

1.The heater should be prepared for deliming as described in the “Why? When and How” booklet. The relief valve may also be delimed at this time.

2.With the Flo-Jug upright:

•Take off cap, remove cover under opening and install 3/4" x 4" pipe nipple.

•Drill or punch a 3/16" vent hole in handle. A stainless steel screw is included with the Flo-Jug kit. This screw is to be installed in the vent hole when Flo-Jug is not in use.

•Remove drain valve from heater and insert a 3/4" x 4" nipple.

•Connect and clamp 1" I.D. x 3" hose to Flo-Jug and heater nipple.

3.Lift the Flo-Jug to the POUR POSITION and permit the UN•LIME to flow into the heater as rapidly as possible.

•Be sure to keep the vent just above the liquid level.

4.Place the Flo-Jug in the DELIME POSITION.

•It may be necessary to place the empty jug on its carton to trap the solution in the heater.

•Allow the UN•LIME to attack the water scale for 5 minutes.

5.Lower the Flo-Jug to the DRAIN POSITION and allow the UN•LIME to flow out of the heater as rapidly as possible.

•Observe the vent holes and elevate the jug slightly if there is a possibility of spillage.

FIGURE 9

FLO-JUG METHOD OF DELIMING

The Flo-Jug is the standard 5 gallon container for UN•LIME -or- it is available as a deliming kit with hose and fittings. Contact your dealer, distributor or the A. O. Smith Water Products Company.

•Deliming activity is indicated by foaming on the surface of the solution.

6.Continue the deliming process:

•Raise jug to POUR POSITION. Allow solution to flow into heater.

•Place jug in DELIME POSITION for 5 minutes. Solution is at work in heater.

•Lower jug to DRAIN POSITION and allow solution to flow out. Observe foaming.

7.After one hour, or earlier if the deliming activity (foaming) stops, inspect the tank interior.

•Drain the UN•LIME back into jug, DRAIN POSITION, and then stand juginDELIMEPOSITION.

•Remove clamp, hose and pipe nipple from heater drain opening.

•Observe interior through opening - a small flashlight may be used effectively.

•If the interior still shows water scale, the deliming process should be continued.

•To check UN•LIME for continued use or reuse, place some lime scale or white chalk into a glass with a small amount of solution. If the material is vigorously dissolved by the solution, the UN•LIME can be reused. If not, the UN•LIME has been weakened and should be replaced.

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