Lochinvar Hot Water Generator - Manual (Page 20)

6
Maintenance
20
Hot Water Generator Installation and Operation Manual
Temperature control valve (optional) -
inspection and replacement
The temperature control valve is installed adjacent to the tube
bundle. The manufacturer’s documentation included with
the unit gives specifics for operation and maintenance of the
control valve. The CAD drawing included with the unit will
give the exact location, as well as interlocks with other
components. This information should be reviewed before
removal / replacement of the temperature control valve.
ƽ ƽ WARNING
Steam or boiler water present situations
that can be very dangerous because of the
high temperatures and pressures.
Use
common sense and follow all accepted and
recommended procedures when
performing installation, operation, and
maintenance procedures to avoid possible
injury or death.
ƽ ƽ WARNING
The combination of electricity and water
can pose a very dangerous situation. Turn
off / disconnect all electric power before
attempting any maintenance procedure.
1. Follow Steps 1 through 5 of the shutdown procedure
(page 10) to take the unit off-line before attempting to
remove and inspect the temperature control valve.
2. Assure that the energy source, condensate / water return
line, cold water inlet, and hot water outlet have been shut
off; that the tank has been completely drained; that the
pressure has been bled from both the water and energy
source systems; and that all components and surfaces
have cooled.
3. If the temperature control valve is electrically activated,
turn off the power and disconnect the leads to the valve.
4. Remove the control valve probe from the tank port.
5. Carefully break the joints between the temperature
control valve and the unions on either side of the valve
per FIG.’s 5 and 6 on page 6 of this manual.
6. Carefully break the connections between the energy
source inlet line and the tube bundle.
NOTICE
It may be necessary to break the lines at
a second location, and for the lines to be
rotated to allow clearance for the
temperature control valve to be
removed from the system.
If it is
necessary, care should be taken to
ensure that in-line components are not
damaged.
7. Remove the temperature control valve from the system.
8. Follow the supplied manufacturer instructions for
inspecting the valve.
If found to be malfunctioning,
replace the valve.
9. Carefully replace the temperature control valve into the
system by reattaching it to the energy source inlet line and
the tube bundle outlet line. Follow recommendations
contained in the manufacturer’s documentation, local
codes, or accepted contractor practices as to the use and /
or type of joint compound or sealer at the connections.
10. Align the valve as it was situated before removal and
tighten the connections. If lines were broken at an
additional location to allow for removal of the valve, be
sure to also tighten those connections.
11. Reconnect the temperature control valve to the system
interlocks and install the sensing probe into the tank.
ƽ ƽ WARNING
If the unit is equipped with a circulating
pump, the pump relay must be interlocked
with the temperature control valve so that
the energy source will shut off if the pump
is not operational. Failure to do so could
create a very dangerous situation if the
pump were to fail.
12. Follow the startup procedure (page 10) to put the unit
back on-line. Carefully check all connections for any sign
of leakage.
Strainers - inspection and replacement
The strainers are installed upstream of the energy source
shutoff valve for the main traps. These strainers must be
blown down periodically (approximately every three (3) to six
(6) months) to prevent the build up of any sediment.
ƽ ƽ WARNING
The combination of electricity and water
can pose a very dangerous situation. Turn
off / disconnect all electric power before
attempting any maintenance procedure.
1. Follow Steps 1 through 5 of the shutdown procedure
(page 10) to take the unit off-line before attempting to
replace the energy source strainers.
2. The location of the strainers can differ between packages.
Reference FIG.’s 3 and 4 on page 5 of this manual to
identify the location of the strainers on the unit.
3. Carefully break the line connections on the inlet side of
both strainers.
4. Carefully break the line connection on the outlet side of
the strainers.
5. Remove and examine the strainers.