Raypak Xtherm 1005A, Инструкция по установке и эксплуатации

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3. Check for leaks. Repair any that are found.
Raypak Integral Cold Water
Protection
XTherm heaters are equipped with an integral cold
water protection system. Units equipped with the dual
injector pump system are designed to operate with
heater inlet water temperatures down to 50°F continu-
ous. Under start up conditions the dual injector system
can operate with fluid temperatures down to 32°F.
Operation at lower temperatures will create unwar-
rantable damage to the injector pumps. XTherm WH
and WHP models equipped with single injector pumps
are designed for typical domestic hot water and com-
mercial pool heating operating conditions respectively.
Contact your local representative or the factory for
applications assistance.
Hydronic Heating
Pump Selection
The heater is equipped with an integral cold water pro-
tection system that includes dual modulating injector
pumps to pull the required flow from the system loop
and a heater pump, sized by the factory, for the opti-
mal ∆T across the primary heat exchanger. The
system is designed for continuous return temperatures
from 50°F to 180°F.
Feedwater Regulator
Raypak recommends that a feedwater regulator be in-
stalled and set at 12 psi minimum pressure at the
highest point of the system. Install a check valve or
back flow device upstream of the regulator, with a
manual shut-off valve as required by local codes.
Piping
All high points should be vented. A heater installed
above radiation level must be provided with a low wa-
ter cut-off device (sales order option F-10). This
heater, when used in connection with a refrigeration
system, must be installed so that the chilled medium is
piped in parallel with the heater with appropriate
valves to pre-vent the chilled medium from entering
the heater.
The piping system of a hot water heater connected to
heating coils located in air handling units where they
may be exposed to circulating refrigerated air, must be
equipped with flow control valves or other automatic
means to prevent gravity circulation of the heater
water during the cooling cycle. It is highly recommend-
ed that the piping be insulated.
NOTE: Hot water heating systems all have unique
levels of operating diversity that must be accounted
for in the system design. The system should always
include adequate system flow in excess of the
connected boiler flow for proper operation. Where
the system flow may drop below the connected
boiler flow a buffer/decoupler may be needed.
Failure to design for adequate flow (i.e. bypasses, 3
way control valves, flow limiting balance devices,
buffer tanks, etc.) will result in boiler short cycling
and may reduce boiler life. Always contact your local
Raypak representative for system design assistance
to avoid these issues.