Remove drain valve, nipples, thermostat and wiring (but not elements). Remove sheet metal shell and insulation. If a secondhand tank is being used, pressure teat it far leaks. To pressure teat do the following steps
1) Screw a 6" galvanized nipple into the drain at the bottom of the tank. Wrap Teflon tape around pipe threads. Screw a hose bib to nipple.
2) Plug the entire inlet holes at the top of the tank except one with 3/4" galvanized plugs.
3) Connect garden hose to water supply and hose bib at the bottom of the tank. Fill tank with water until flowing out the top of the tank. Turn off water.
4) Plug remaining inlet hole with plug and turn water back on.
5) Look for leaks. Leaks around elements can sometimes be fixed with a new gasket. Leaks around the base of the unit are beyond repair. If there are no leaks drain tank and remove hose bib from drain nipple.
Unscrew anode rod at the top of the tank and cheek its condition, replace if necessary. Remove any rust on the tank with sandpaper. Spray tank with high temperature flat black stove paint.
Determine the inlet hole in the top of the tank. Select the inlet holes which is on the opposite side of the tank from the tank drain and screw into it a 6" galvanized nipple. Screw an elbow on the end of the nipple. Screw a 14" nipple into elbow and rotate until the nipple is in line with the tank's drain. All the inlets at the top of the tank should plugged except for the one with the nipple (See Figure 5).
Selective surface increases the collector's performance. It should be applied just before the tank is installed in the collector for the final time. This avoids damaging the selective surface while handling the tank during the construction of the collector. The selective surface should be applied to the forward facing half of the tank (See Figure 5).
