THERMO 2000 DTH 102, Инструкция по использованию и уходу

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DTH Electric Boilers USE & CARE MANUAL
(Revision June 2014)
, Page
10.
3.5 ELECTRICAL POWER SUPPLY
Wiring must conform to the National Electrical
Code and to state or local code requirements.
The electric boiler must be electrically grounded
in accordance with local codes, or, in the
absence of local codes, with the National
Electrical Code.
3.5.1 240Vac models
Wiring must be from a 240 Volt (single phase,
60 Hz) circuit protected by a properly sized
breaker. Wire gage (2 wires+ ground) must be
properly sized. Consult the boiler rating plate to
select the proper breaker and wire gage.
3.5.2 480 or 600Vac model
Line wiring must be from a 480 or 600 Volt ( 3
phase, 60 Hz) circuit protected by a properly
sized breaker. Wire gage (3 wires+ground)
must be properly sized. Consult the boiler rating
plate to select the proper breaker and wire gage.
3.6 PUMP POWER SUPPLY
3.6.1 240Vac, 480 and 600Vac models
Use a relay (Honeywell #RA-889, RA-89A) or
the secondary contact of a zone valve (if the
heating system is zoned using 4-wire zone
valves). When a thermostat calls for heat: the
relay will power either the boiler pump or the
zone valve (the zone valve will power the boiler
pump upon opening fully). See figure 7 for more
details.
If the heating system is set up to use only a
single pump, then to minimize flow by gravity &
heat loss during non-draw periods, a flow check
must be installed.
3.7 CONNECTING THE THERMOSTAT
The thermostat shall not be connected directly
on the boiler. Its function is to activate the
circulating pump(s) to bring cold return water
from the heating system to the boiler. The
heating element will then be activated to raise
the boiler temperature. The boiler is always
maintained hot.
3.7.1 For 240Vac, 480 and 600Vac models
3.7.1.1 Single heating zone
Connect the low voltage thermostat to a relay
(Honeywell #RA-889, RA-89A). See figure 7.
3.7.1.2 Multiple heating zones
Zone valve zoning
Connect the low voltage thermostat to the zone
valve. Components must be wired to ensure that
only the zone valve corresponding to the zone
calling for heat is actuated and that the circulator
is powered on a demand from any zone.The
transformer used to power the zone valves must
be sized for the load represented by all zone
valves in the heating system.
Circulator zoning
Connect the low voltage thermostat to the relay
(Honeywell #RA-889, RA-89A). Components
must be wired to ensure that only the circulator
corresponding to the zone calling for heat is
actuated.