LAARS EDN Series - Installation, Operation and Maintenance Instructions - Manual (Page 17)

Endurance Page 17
8. Connect boiler feed water supply with shut off
valve to inlet connection of automatic fill valve.
Locate in boiler outlet piping.
9. If codes require, install suitable back flow
preventer between automatic fill valve and city
main.
10. The appliance may be installed in single and
multiple zone systems (using either zone valves
or zone circulators) in the same manner as any
other residential boiler.
Caution
The EBP/EDP appliance must not be direct
connected to a heating system utilizing oxygen
permeable tubing (see warranty). Provide a water to
water heat exchanger between systems to prevent
corrosion of tank or other components. Non-toxic
heating system antifreeze may be added to the
hydronic system provided that the concentration
does not exceed 35% and the antifreeze contains
an anti foamant.
4.2 Use in a Combined Hot Water Heating
and Chilled Water Cooling System
When the appliance is used in connection with
a refrigeration system, it must be installed so that the
chilled medium is piped in parallel with the boiler with
appropriate valves to prevent the chilled medium from
entering it.
The boiler piping system of an appliance
connected to heating coils located in air handling
units where they may be exposed to refrigerated air
circulation must be equipped with flow control valves
or other automatic means to prevent gravity circulation
of the boiler water during the cooling cycle.
4.3 Water Quality and Treatment
Water quality control is steadily increasing in
importance in view of the use of modern regulation
technology and the modern boiler designs used in
central heating systems.
The life of a central heating boiler can be
severely diminished as a result of the formation
of scale deposits and/or corrosion products. The
formation of such deposits should be prevented
wherever possible.
Continual water make-up is not permitted.
A suitable water treatment may be used to
prevent excessive scale deposits in the boiler and
corrosion in the system.
4.4 Anti-Freeze
Proper precautions for freeze protection are
recommended for boiler installations in areas where
the danger of freezing exists.
4.4.1 Endurance Boiler Low
Temperature Feature
Endurance boilers are equipped with a Low
Temperature control feature that recognizes when the
water temperature at the outlet of the boiler has fallen
below 39°F (4°C). If this condition is recognized, the
Endurance pump will run for 5 minutes, or until the
boiler outlet temperature reaches 45°F (7°C). If the
boiler outlet temperature remains below 45°F (7°C)
for 5 minutes, the appliance will start its ignition
sequence, in hopes of firing the boiler and heating the
water. The display will show [ICE] during this time.
This feature is intended to assist in protecting
the boiler from freezing conditions, and does not help
to protect any other part of the heating system. This
feature will only help when there is power to the boiler
and when the internal water flow components in the
Endurance are working properly. This feature will
not be able to prevent freezing if the low temperature
water condition persists. See Section 4.4.2 for
information concerning further freeze protection for
the Endurance.
4.4.2 Anti-Freeze Boiler Additives
Caution
Power outage, interruption of gas supply, failure of
system components, activation of safety devices,
etc., may prevent a boiler from firing. Any time a
boiler is subjected to freezing conditions, and
the boiler is not able to fire, and/or the water is
not able to circulate, there is a risk of freezing
in the boiler or in the pipes in the system. When
water freezes, it expands. This can result in bursting
of pipes in the system, or damage to the boiler,
which could result in leaking or flooding conditions.
Do not use automotive anti-freeze. When the
Endurance is the combination space heating domestic
water model (EBP), a non-toxic anti-freeze, such as
propylene glycol, must be used. Maintaining a mixture
of minimum 65% water and maximum 35% properly
inhibited HVAC glycol, which contains an anti-
foamant, is the preferred method of freeze protection
for Endurance boilers. Percentage of glycol used
in the Endurance boiler must not exceed 35%.
Typically, this mixture will serve as burst protection
for temperatures down to approximately -35°F (-30°C).
IMPORTANT NOTES: Different glycol products
may provide varying degrees of protection. Glycol
products must be maintained properly in a heating
system, or they may become ineffective. Consult the
glycol specifications, or the glycol manufacturer, for
information about specific products, maintenance
of solutions, and set up according to your particular
conditions.