Raypak XTherm 2505, Инструкция по установке и эксплуатации

Страница: 16 / 66

16
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 prevent 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 automat-
ic means to prevent gravity circulation of the heater
water during the cooling cycle. It is highly recommend-
ed that the piping be insulated.
Air-Separation/Expansion Tank
All heaters should be equipped with a properly-sized
expansion tank and air separator fitting as shown in
NOTE: All hot water heating systems 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.
Pump Selection
The heater is equipped with an integral cold water
protection system that includes a proportional two-way
valve, which in conjunction with an on/off injection
pump (shipped loose), will provide the necessary
flow from the system loop and a heater pump, for the
optimal ΔT across the primary heat exchanger. The
system is designed for continuous return temperatures
from 50°F to 200°F.
Feedwater Regulator
Raypak recommends that a feedwater regulator be
Fig. 15: Hydrolic Piping
Fig. 14: Injection Pump
Table F: Injection Pump Dimensions
Model
No.
A B C D E F G H J
2505
3-1/2 19 13-1/2 16-1/8 N/A N/A N/A N/A N/A
3005
3-5/8 21 16-1/2 19-1/2 N/A N/A N/A N/A N/A
3505
10 10 6-5/16 10-1/2 13-15/16 5-5/16 6-5/16 1/4 7-7/8
4005