Comprehesive Boiler Manual Jan 2019

5) Hartford Loop
The Hartford Loop invented in 1919
by the boiler insurance company
made steam boilers safer as the
low water cutoff had not yet been
invented.
1895, Denver: Gumry Hotel, 22 deaths.
Cold water into a partially empty boiler.
Boilers in these systems are usually
located at or below ground level
for proper gravity flow of
condensate. No condensate tank
is needed.
The Hartford Loop prevents
water from draining
backwards into leaking
condensate lines (wet return)
Dry return is above
the water line and
wet return in below
the water line
Check valve in lieu
of Hartford Loop
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