Bradford White Ecostor SC, Инструкция по установке и эксплуатации

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Pre-installation continued-
SOLAR WATER HEATING WITH ELECTRIC BACKUP FUNDAMENTALS
When hot water is taken from the tank, cool water is delivered to the tank bottom by means of a diptube.
The solar heating system puts the most amount of heat into the storage tank when the internal heat
exchanger is located in this cooled location. This allows the solar collector temperature to be lower and
still transfer heat into the storage tank.
In dual heating element models, the thermostat to turn on the lower heating element is located above the
internal heat exchanger. This ensures that the heat exchanger stays in a cool zone unless the solar heating
system cannot keep up with demand and backup heat is needed. If the lower heating element thermostat is
activated, this is an indication that there is not enough solar heating available to meet the immediate need.
Approximately 1/3 of the storage tank volume needs to be removed
without sufficient solar heating for
the lower element to energize. The dual electric element backup will allow the entire storage tank to hold
hot water during these periods. The unique design promotes solar heating yet does not compromise heater
performance when it is not available.
In single heating element models during periods were solar heating is not available, the solar water heater
can store hot water in about ¼ of the tank volume.
The amount of heat transferred into the tank due to solar heating is inconsistent. The more heat stored in
the tank through solar heating, the lower the operating costs. The supplied ASSE thermostatic mixing
valve or equivalent must be installed to ensure that if higher temperatures are achieved, safe water
temperature delivery occurs. It is recommended that storage tank temperatures are not allowed above
185°F. Temperature levels above that point may activate the electric backup emergency cutoff device,
disconnecting the electric backup system. The electric backup system must then be manually reset at the
water heater to resume electric backup operation.
NOTICE
For California installation this water heater must be braced, anchored, or strapped to
avoid falling or moving during an earthquake. See instructions for correct installation
procedures. Instructions may be obtained from California Office of the State Architect,
400 P Street, Sacramento, CA 95814.