QUENCH Valve

TM 5-4120-356-14

( f ) R e f e r t o f i g u r e 4 - 4 a n d e v a c u a t e t h e r e f r i g e r a n t system .

( g ) Charge the system with refrigerant in accordance w i t h the pro-

c e d u r e s given in paragraph 4-10.

k. QUENCH

Valve

(1) Inspection.

( a ) T u r n t h e s e l e c t o r s w i t c h t o the "OFF" position and disconnect

the air conditioner from the electrical power source.

( b ) Remove the condenser fan i n accordance with paragraph 3-15b.

( c ) R e f e r t o f i g u r e 4 - 1 2 a n d i n s p e c t the quench valve, power bulb

and tubing for obvious defects.

( d ) Check the quench valve for leaks in accordance with paragraph

If quench valve is leaking refrigerant, refer to step (4) for repair.

(2) Test.

( a ) Refer to figure 4-12 and tape the bulb of a thermometer to the

s u c t i o n line near the quench valve power bulb.

(b) Refer to figure 4-5 and install a suction pressure gage.

the

fan

and

install

and

secure

all

panels

the air conditioner.

(d) Connect the air conditioner to the electrical power source, turn

t h e selector switch to the "COOL" position and turn the thermostat control knob counter-

c l o c k w i s e to its limit. Operate the unit on "COOL" for approximately 30 minutes to

stabilize the thermometer reading.

( e ) Note the pressure indicated on the suction pressure gage. To

t h i s a d d 2 p s i g ( 0 . 1 4 k s / c m2s t i m a t e d s u c t i o n l i n e l o s s .

(f) Refer to table 4-2 and convert pressure (gage pressur plus 2 psig

(0.14ks/cm ) temperature.

( g ) Calculate superheat of quench valve by deducting temperature

c a l c u l a t e d in step (f) above from temperature indicated on thermometer attached to

t h e s u c t i o n l i n e . S u p e r h e a t of the quench valve should be 30.4 0.5F (-0.88

0.5C).

(h) If superheat of quench is not correct as given in step (g) above,

refer to step (3) and adjust the quench valve to the correct superheat.

(i) If superheat of quench valve is correct, proceed as follows:

( j ) Remove the condenser fan and remove the thermometer bulb from

t h e suction line near the quench valve power bulb.