LAARS EDN Series - Installation, Operation and Maintenance Instructions User Manual
Page 13

Endurance
Page 13
Figure 20. Single Zone With Room Thermostat (internal
pump provides system flow).
Figure 21. Single Zone with Added Circulator(s) and
Room Thermostat(s).
ENDURANCE
FIELD WIRING BOX
ENDURANCE
FIELD WIRING BOX
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 curtailed 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.
Figure 22. Multiple Zones Utilizing Four Wire Zone Valves with (Dry) End Switches.
A suitable water treatment should 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