Sol-Reliant OG 300-2004008A, Installation, Operation And Maintenance Manual

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9
Roof Flashing
The Sol-Reliant uses a single stainless steel flashing for both pipes penetrating the roof. With
the accompanying rubber boot it allows water-tight penetrations in a single, well-protected
location. The Sol-Reliant uses no-caulk flashings for all other flashings, one for each of the
standoff brackets that support the collector and another for the electrical weatherhead.
Pressure and Temperature Relief
The Rheem Solar Pre-Heat Storage Tank includes a
temperature and pressure relief valve (P & T valve) located
on top of the tank. This is an emergency over-temperature
and over-pressure valve to protect the tank. If the valve
opens for any reason, water under pressure will discharge for
a several seconds.
Toggle Switch and High Limit Switch
The pump circuit contains two switches: One is a manual “On/Off” switch located on top of the
grey electrical box that is attached to the tank next to the flow meter. The other is a high limit
switch installed against the internal wall of the solar storage tank behind the grey box. In order
to preserve the glycol, this White-Rogers #3 LOI-181 switch will open the circuit to the pump
(which shuts the pump off) when the internal tank temperature of the potable water is at 180
degrees F. In the event the temperature reaches 170 degrees in the top of the solar tank, the
system shuts down in order to preserve the glycol. The switch will close at 140 degrees enabling
the pump to operate again if there’s sun.
NOTE:
When the pump shuts off, the fluid in the collector drains back into the reservoir
mounted behind the solar thermal collector. This results in the collector being empty or
“stagnant.” Even though the collector can achieve temperatures over 400 degrees F, it is
harmless for it to be empty. Since the heat transfer fluid drains out of the collector into the
reservoir, it is protected from the excessive temperatures that can cause it to degrade.
Solar Loop Pressure Relief Valve
A 125 p.s.i. 3/4” Watts 3 L pressure-only relief valve is located just below the
bottom of the photovoltaic module above pipes going through the roof. This
is an emergency relief valve protecting the pump and the solar loop
components from excessive pressure. Since the solar loop is not pressurized,
it is very unlikely this valve would ever be used.
Piping materials
Due to the high temperatures that can occur in a solar water heating system, only copper pipe is
used. Type “M” copper is used on the closed solar loop piping. Any threaded piping or threaded