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H2O BOILER
HC SERIES IOM Manual
1.5
Freeze Protection and Storage
In either an open or a closed loop configuration, the boiler must be isolated before draining. Due
to the radial geometry of the unit, it can only be drained by forced air method. The operator can
connect the forced air through the 3/8” air vent on the manifold and the drain connection on the
3/8” connection on the other manifold.
For short term storage, the operator can add antifreeze to protect the boiler against freezing
condition. In this case, the boiler or water heater does not need to be drained. The antifreeze must
be compatible with hydronic heating systems.
1.6
Water Treatment
All heat exchanger coils are constructed from high grade stainless steel. Therefore, high oxygen
content in the feed water should not result in any corrosion inside the coils. Since water flow
through coils is in turbulent mode, and they are continuously expanding and contracting; the
operation of the unit is to a large extent self-cleaning. Therefore, other potential minerals that may
exist in water should not have any adverse effect (on the tubes). However, if it is wished to supply
soft water to the boiler or water heater, then a sodium-based ion-exchanger may be used. Note that
“soft water” is defined as one having less than 0.12
British, or 0.17
US hardness level. Consult a
local water treatment consultant to determine if water treatment is required.
WARNING:
Exceeding the maximum allowable gas manifold pressure could result
in over-firing of the unit and may cause permanent damage to the unit.
NOTES:
Air and gas flow rates are factory adjusted for optimum combustion
quality. Note that these settings may vary slightly at different site
conditions (calorific value of gas, duct length, elevation, etc.)
After installation is completed, using a gas analyzer, the CO and O
2
contents of the exhaust gases should be re-checked to ensure their
compliance with those achieved at the factory and reflected in the test
report provided to your local
H2O BOILER
representative.
IF adjustments to the factory settings of air and gas flows are made,
ensure that the manifold gas pressure does not exceed the pressure
specified on the boiler label.
NOTES:
Boiler/water heater can be used in both closed loop and open loop (one
pass) operations.
In the commonwealth of Massachusetts the installation shall be carried out
by a licensed gas fitter/plumber and comply with 48CMR
D-VAC Sales Inc. Email: dmann@dvachvac.com Tel: (516) 256-3131 www.dvachvac.com
