Determine the Total Fluid Volume
If original capacity is not known, use Table 5-4 and add up the fluid capacity of all
the system components and piping. If the collectors' or heat exchanger labels
indicate fluid capacity, use that number. If not, use the number in the chart. Ignore
the fluid capacity of the expansion tank or tanks, pumps, valves and other
components not listed above.
Determine the Number and Size of Expansion Tank
The fill pressure table (Table 5-5) is based on expansion tanks manufactured by
Amtrol, Inc. If Amtrol tanks are not used on the solar system, ask the design
authority for assistance in determining the "Amtrol equivalent" of the existing
expansion tank or tanks.
In Table 5-5, 1 x15 refers to a single #15 ExtrolTM tank, 1x30 refers to a single #30
tank, 15+30 means a #15 and a #30, and 2x15 means two #15 tanks. Other listings
follow the same pattern.
Determine the System Fluid Temperature During Filling
Use a thermometer in the charging bucket to measure the temperature of the fluid
while you are charging the system. The fill pressure chart adjusts the final fill
pressure based on the fluid temperature.
Determine the System's Elevation Above Sea Level
It is necessary to make an adjustment to both the expansion tank air pressure and
the recommended system fluid pressure for the site's elevation above sea level.
5.2 REPAIR PROCEDURES