Installation

As mentioned earlier, the specific details of installation vary from site to site. In general, though, the first step is to prepare a suitable foundation. (Refer to the previous article for information on proper site selection.) Photo Ten shows how we built a three-sided concrete foundation to support the batch heater shown on the cover. A slab foundation would also work for this type of built-in installation, while pressure-treated posts would be perfectly adequate for a freestanding mount (see Illustration C in the previous article). In cold climates, the foundation must extend below the frost line. If your batch heater will be built against your home, you can run the plumbing straight from the batch heater's tank, through the home's exterior wall or foundation, on to the existing water heater. (We drilled a four-inch hole in the home's concrete foundation and lined the hole with a piece of PVC drainage pipe. Wherever you drill, be sure to seal the penetration and stuff any gaps with insulation.)
If your batch heater is mounted some distance away from the house, it's best to run the pipes in a small, underground trench to minimize heat loss.
Whether freestanding or built-in, your batch heater should be mounted in an insulated enclosure whose tilt approximately equals the geographical latitude of your home. If you opt for a freestanding mount, you should sheathe the batch heater frame with exterior- grade plywood, creating a weatherproof box. Then simply mount the box on the foundation: A cross-braced frame of 2 X 4s is fine. Built-in mounts can also be very simple: Photo Eleven shows the simple lean-to framework we used to

Right Connecting the batch heater to the existing plumbing is a matter of adding the six valves and the associated fittings as shown in color. Of course, you should turn off the water and the power to the water heater before making your alterations. Otherwise, it's a straightforward matter of soldering the parts in place, just as you see them here.

mount our built-in batch heater. To allow for any movement or settling of either the house or the heater, the frame leans against the home's siding but is not directly attached. In both cases, extrafiber glass or rigid insulation should be added to bring the enclosure's total R- value to at least 16.

Photo Eleven A batch heater's enclosure doesn't have to be elaborate, as you can see from the simple framing we used on ours. This framework was covered first with insulating sheathing and then with exterior siding chosen to match the home's original finish.

While mounting the batch heater's frame (when everything is still accessible), reinstall the tank support brackets and mount the water tank inside the reflector frame. Run 1/2" CPVC supply-and-return pipes from the existing water heater to the batch heater, and connect the batch heater to the CPVC, using the fittings marked "site assembled" in Illustration E. Then connect the CPVC to your existing plumbing.
Illustration H shows the proper plumbing layout for homes in which the water heater is in the basement: The drain valves, as shown, are at the lowest point of the solar loop's plumbing. This insures that the solar system will drain properly. But if your water heater is in a location higher than your batch heater's, plumb your system exactly as shown, and then add two more drain valves (one in the hot line, one in the cold) at the solar plumbing's lowest point. These two additional valves should be opened in conjunction with the valves shown in Illustration H when you wish to empty the batch heater.
When your system is plumbed, turn on the water and fill the system, then continue with the finish work on your enclosure. From time to time, inspect every fitting in your solar plumbing for leaks.