Bradford White 46392H, Инструкция по установке и эксплуатации

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Pre-installation continued-
NOTICE
Increasing the boiler DOE heating capacity above the
values listed in Table 3 will not increase the rating of
the water heater.
2. Circulator Sizing – Refer to Table 5 for the
corresponding pressure drop through the coil for the
given model. Calculate the pressure drop of all straight
pipe and fittings on the supply and return of the water
heater at the selected flow rate. Add the piping/fitting
pressure drop to the pressure drop through the water
heater coil.
Select a circulator that will provide an appropriate flow rate
at the combined pressure drop.
SYSTEM ZONE CONTROL
The indirect-fired water heater must be installed as a zone
separate from the space heating system. The domestic hot water
zone’s piping and circulator must be sized for a minimum flow
rate with all zones in use and a maximum flow rate with only the
water heater in use. For this reason, the preferred method of zone
control is with circulators.
1. Circulators – With space heating zones using
circulators, the indirect-fired heater should be added as
an additional zone with a circulator.
2. Zone Valves – Select a valve with a low-pressure drop to
assure adequate flow through the water heater.
3. Hybrid – The space heating zone can be zoned using
zone valves and the indirect-fired heater zoned with a
circulator.
DOMESTIC HOT WATER PRIORITY
Two options are available, Priority and Non-Priority.
1. Priority – Demand for space heating is interrupted or
postponed until the domestic hot water demand is
satisfied. This option provides maximum delivery of
domestic hot water. Priority is recommended when: