Mitsubishi Electric EHST20C-VM6HA Service Manual page 67

DISASSEMBLY PROCEDURE
13. How to remove the expansion vessel
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Swing the control box to the front. (Refer to Procedure 4.)
(3) Remove the flare nut using two spanners: one to hold the
flare joint and the other to turn the flare nut.
(4) Displace the pipe slightly downward and pull out the
expansion vessel.
(5) Remove the flare joint from the expansion vessel.
w When reinstalling the flare joint, use a new 3/8" gasket.
Note: To avoid dropping of the expansion vessel, hold it
by hand when removing it.
14. How to remove the temperature and pressure (T&P)
relief valve (EHPT20X-VM2HA only)
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Swing the control box to the front. (Refer to Procedure 4.)
(3) Remove the field piping from the temperature and
pressure relief valve.
(4) Turn the back nut (1-3/4") using a specified tool and remove
the temperature and pressure relief valve. (Photo 14-2)
(5) Eliminate locktite on the thread surfaces using remover.
(Photo 14-3)
w Before reinstallation, apply locktite over the thread surface
on the temperature and pressure relief valve and install the
temperature and pressure relief valve with the T&P joint
and the back nut.
w When reinstalling the T&P relief valve, point the nut to the
bottom as specified. (Photo 14-1)
w For more details about the locktite and the remover, refer
to Page 71.
w When reinstalling the T&P, use a new 1-3/4" gasket.
15. How to remove the air vent (manual)
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Remove the air vent (manual) with a flare joint using two
spanners: one to hold the flare joint and the other to turn
the flare nut.
(3) Remove the flare joint from the air vent.
Photo 13-1
Expansion vessel
Photo 13-2
Photo 14-1
T&P relief valve
(*2) The JIG is set as a service part.
Photo 14-3
T&P joint
Photo 15-1
Flare joint
Air vent (manual)
67
PHOTOS
Flare joint
Flare nut
Flare joint
Gasket (3/8")
Photo 14-2
JIG (for back nut) (*2)
Nut
Back nut (1-3/4")
Back nut
T&P relief valve
Threads for application of loctite
Flare nut
Pipe