Hookup 999 The cadmium sulfide cell, or cad cellular, falls under the main regulation program and is always feeling

Hookup 999 The cadmium sulfide cell, or cad cellular, falls under the main regulation program and is always feeling

the presence of the oil burner flame. The cad mobile system is comprised of the exact cell, a holder, and wire to get in touch the cell towards the major controls. This alarm is actually installed in the air pipe in the burner in such a way on view the flame.

The cad cellular is manufactured out of a cadmium sulfide coated ceramic disk with a conductive grid over their area. Electrodes include attached to this surface, and mobile was enclosed in cup to guard they. The cad cellular in dark provides a really high resistance to the flow of electric latest. Yet, within the appeal of apparent light, this has a tremendously low resistance. For an adequately modified burner, during operation, the cad cellular weight should always be more or less 300-1000 ohms, yet not significantly more than 1600 ohms. A resistance above 1600 ohms signals problems that needs to be remedied.


To appreciate ideas on how to diagnose the cad cellular, it is critical to very first learn how the controls functions.

Initially, the regulation must-have a higher opposition across the F-F terminals (cad cell will not notice obvious light) before it will attempt to start the burner. In the event the cad mobile senses light or is shorted, the exchange into the major control wont pull in to start out the burner. When the burner was working as well as the flame is established, ceny russiancupid the cad cell need the lowest resistance (cad cellular feeling fire) to help keep the primary controls from locking out on safety.

Symptom no. 1

Let’s say the burner wont start and also the cad cellular are suspected? The task for resolving this issue will be earliest to ensure the thermostat is demanding heating hence discover range voltage towards the regulation. Next eliminate one lead associated with the cad mobile through the F-F terminals. In the event that burner starts, this implies that the cad cell is sometimes witnessing outside light inside property, cad cellular cables is pinched, the construction is shorted, or the cell is actually faulty. You may want to protect the cell from external light, restoration pinched cables, or put in a new cad mobile.

Sign # 2

Can you imagine the burner starts but locks completely plus the cad mobile is suspected? This symptom initially implies that the regulation did start to see the high weight necessary to starting the burner. But while in the lock-out timing years, they decided not to feeling the reduced weight throughout the cad cell required to keep carefully the burner working. As previously mentioned earlier in the day, the regulation need no more than 1600 ohms of resistance to avoid random lock-out.

To diagnose this problem, begin the burner and ahead of the safety lock-out timing period ends

detach the cad cellular cables from F-F terminals from the regulation. Subsequent, jumper the F-F terminals with an article of line or use a 1500 ohm resistor. This may enable the burner to carry on running to make sure you should be able to look into the cad cell opposition through the operate routine. Any time you wouldn’t get the F-F terminals regarding control jumpered prior to the burner closed , hold off 3-5 moments before attempting this once more. Using the burner operating, hook the ohmmeter throughout the cad cellular leads. Make use of the information above and also the opposition your assess regarding the cad cell to discover the cause together with suitable motion recommended for solving the difficulty.

The cad mobile controls program has proven to be extremely reliable within our industry. This brief technical topic should assist you to are more familiar with their procedure and software. Recall, if it is set up in order that it can sight the flame properly, try tightly protected, and it is held thoroughly clean, you will probably posses numerous years of continuous service.