Instructions / Assembly

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additional requirements. If the boiler supplies hot water to heating coils in air handler units, flow control valves or other devices must be
installed to prevent gravity circulation of boiler water in the coils during the cooling cycle.
Chilled water medium must be piped in parallel with, and isolated from, the boiler. Freeze protection for new or existing systems must
use glycol that is specifically formulated for this purpose. Antifreeze must include inhibitors that will prevent the glycol from attacking the
metallic system components. Make certain that the system fluid is checked for the correct glycol concentration and inhibitor level. The
system should be tested at least once a year and as recommended by the producer of the glycol solution. Allowance should be made
for the expansion of the glycol solution in the system piping. Example: 50% by volume glycol solution expands 4.8% in volume for a
temperature increase from 32
o
F to 180
o
F, while water expands 3% with the same temperature rise.
G. PIPING DETAILS
Mixing valves are required for the protection of low temperature loops.