Lochinvar Efficiency-Pac EW 150 -- 300, Инструкция по установке и обслуживанию

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30
Installation & Service Manual
4
System piping
Figure 4-1 Connection to the Appliance
Inlet and Outlet Connections
For ease of service, install unions on inlet and outlet of the
appliance. The connection to the appliance marked “Inlet”
on the header should be used for return from the system.
The connection on the header marked “Outlet” is to be
connected to the supply side of the system.
Relief Valve
This appliance is supplied with a relief valve(s) sized in
accordance with ASME Boiler and Pressure Vessel Code,
Section IV (“Heating Boilers”). The relief valve(s) is installed
in the vertical position and mounted in the hot water outlet.
No valve is to be placed between the relief valve, and the
appliance. To prevent water damage, the discharge from
the relief valve shall be piped to a suitable floor drain for
disposal when relief occurs. No reducing couplings or other
restrictions shall be installed in the discharge line. The
discharge line shall allow complete drainage of the valve
and line. Relief valves should be manually operated at least
once a year.
CAUTION
Avoid contact with hot discharge water.
Water Flow Switch (if equipped)
A water flow switch is available as a factory supplied option
on 150,000 through 300,000 Btu/hr water heaters. The flow
switch should be wired across the X and B terminals on
the appliance’s internal terminal strip. Remove the jumper
between the terminals before connecting flow switch wires
to the terminals. This wiring connection installs the flow
switch in the 24 VAC safety circuit for the ignition control.
A flow switch installed in 1 1/4" pipe requires a minimum
flow of 10 GPM to make the flow switch and start burner
operation. A flow switch installed in 1 1/2" pipe requires a
minimum flow of 13 GPM to make the flow switch and start
burner operation. A flow switch installed in 2" pipe requires
a minimum flow of 19 GPM to make the flow switch and
start burner operation. A water flow switch meets most code
requirements for a low-water cut off device on appliances
requiring forced circulation for operation.
Figure 4-2 Water Flow Switch
Low Water Cutoff (if equipped)
A hot water supply appliance installed above radiation level
must be provided with a low water cutoff device either as
part of the appliance or at the time of installation.
An electronic or float type low water cut off is available as a
factory supplied option on all appliances. Low water cutoffs
should be inspected every six months, including flushing of
float types.
Water connections