Troubleshooting

Level Controller

The neon indicator of liquid level controller indicates the "ON" and "OFF" positions of solenoid valve. In the proper installation the "ON-OFF" cycle of the controller is controlled by adjustment of hand expansion Valve. The hand Expansion Valve should be set such that the Solenoid valve is ON for 10 to 20 minutes approximately. These timings are only indicative and might vary in particular application depending upon seasonal conditions and loading and defrosting conditions. The golden rule is that the hand Expansion should be set at full load such that Solenoid valve remains in the open position approximately 80% of the time and thereby provides smooth flow of liquid refrigerant to the evaporator. This will avoid flood back due to surging & short cycling of the Solenoid Valve. Increase the hand Expansion setting quarter thread per hour until the float is full of liquid. This be tested by ice formation on the float chamber, and if hand is sticking on the float chamber. Then it definitely indicates the presence of liquid Ammonia inside, or simply by monitoring LED display Connect 230 VAC supply on the controller. Keep the level knob and the differential knob of Electronics Control panel on '2' & '2' respectively. Keep the coil connections intact and open the cap of the float chamber. Remove the coil from the float chamber keeping the connections intact the dummy float consists of a pipe which has magnetic properties identical to the pipe attached to the float and the movement of the float can be simulated by inserting the dummy pipe inside the coil. Whereas Bar Graph display module- indicated the movement of liquid level inside the float chamber.

When the pipe is completely inside the coil it simulates the coil it simulates the float chamber being full with liquid and the ball being lifted up completely pushing, the magnetic pipe inside the Pickup coil. 'The Neon should go "OFF'(all LED's GLow) stopping the liquid Ammonia through the solenoid. If it does not go 'OFF', then open the coil circuit by disconnecting either terminal 3 or terminal 4 (pick-up coil) of the connections on connection strip. 'Then the Neon indicator should go 'OFF'. Now, if it does not go 'OFF' then look for fault (a)-(iii). If it goes 'OFF', then look for fault (a)-(ii). However, if the insertion of dummy pipe in the coil makes the neon go 'OFF', then remove the pipe.Now, if it becomes 'ON' (Only one or two LED's Glow) then coil and electronic uint are not faulty. Then check for fault (C)-(i) and (C)-(ii) given below. Also, if the Neon is continuously 'OFF ' check for faults. (b)-(i) and (b)-(ii).


(a) Neon indicator is continuously 'ON'
(The LED display module indicates only one or two LED's ON)
(i) Check Receiver Liquid Level. May be too low.
(ii) Float coil & coil wiring are faulty.Repalce the coil or change the coil wires.If the neon indicator does not go "OFF"
(iii) Electronic unit is faulty.Get it replaced from the factory.
(iv) Hand expansion setting is too low.Increase the hand expansion setting quarter thread per hour until the float is full of liquid.(observe the LED display)
(v) Ball is struck or punctured.

(b) Neon Indicator is continuously "OFF"
(All LED's are glowing "ON" LED display panel)
(i) Coil and coil wiring are faulty. Repalce the coil or change the coil wries.
(ii) Electronic unit is faulty.Get replaced from the factory.
(iii) Solenoid valve might leaky. Check the coil, plunger and seat of Solenoid Valve.
(iv) Ball is stuck. Clean Chamber.

(c) The ball in the float chamber is not rising .
(Few LED's Glow- rise & fall of level is not observed)
(i) The ball must be sticking or there might be dirt accumulated on the ball or the ball must have stuck in the dirt below. Clean the dirt and other foreign matter.
(ii) The ball itself is leaky or leaking through the welding. It is recommended to ask for one from the factory.<
(d) Fuse Failure
(1) Check whether it is blown off.
(e) Fuse blows off immediately after power "ON"
(i) Check Solenoid coil is shorted.
(ii) Check all the parallel paths of solenoid coil supply such as neon indicator.

LIST OF RECOMMENDED SPARES:
i) Float Ball
ii) Float Coil
iii) Electronics Unit
iv) Gasket
v) Dummy Float