Laars MASCOT LX, Руководство по обслуживанию

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49
Mascot LX Service Manual
Pressure Relief Valve
If the system pressure exceeds the relief valve setting,
the pressure relief valve is designed to open and release
the excess pressure and water. Note - This type of valve
is designed to relieve a limited number of times during
its life cycle, so it is not a good idea to “test” the valve by
tripping the small metal handle on top. Sometimes when
this type of valve is opened, it will not re-seat correctly,
causing a slow leak. If this happens, and the valve can-
not be cleared, it must be replaced.
Replacement Procedure -
Tools and equipment required:
• Plumber’s torch, solder, and flux
• Two pipe wrenches
• Pipe dope or Teflon® tape
Procedure:
1. Turn off power to the system. Use the main discon-
nect switch mounted on the front panel.
2. The pressure relief valve is mounted on a separate
“T” fitting attached to the outlet pipe unit.
3. Disassemble and remove the drain pipe.
4. Unscrew the valve from the water outlet pipe using
the two pipe wrenches.
5. The replacement valve must be the correct size and
capacity to match the size of the Mascot LX unit.
Check the old valve for two important numbers:
• The capacity of the old valve, listed in BTU
• The relief pressure of the old valve, listed in
p.s.i.
These numbers will be marked on the body of the
valve. Check for this before you get a replacement.
The replacement valve must have ratings for both
BTU and psi which are the same as or higher than
the ratings on the old valve.
Fig. B15-1 - Pressure relief valve (typical)
Note -
Normally a
drain pipe
would run
from here to
within 6” of
the floor.
6. Wrap a piece of Teflon® tape around the threads on
the end of the vertical pipe. Install the new valve us-
ing the two pipe wrenches.
7. Reassemble the drain pipe.
Always re-install the drain pipe. If the pressure relief
valve were to open without the drain pipe in place,
the boiling water could shoot out, causing personal
injury or property damage. Most plumbing codes
call for the drain pipe to extend straight down to a
point about 6” above the floor. Check your local
code.
B15