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19 Cards in this Set
- Front
- Back
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What is an interrupted pilot ignition system? |
Once the main burner is lit, the ignition system proves the main burner is lit, and then shuts off the pilot. |
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What is an intermittent pilot ignition system? |
The pilot is not extinguished after ignition of the main burner. (Honeywell smart valve) |
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What is the recommended spark gap for an intermittent pilot assembly? |
1/8” |
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What is the difference between a dual rod and single rod pilot assembly? |
Dual rod has a ignitor and flame sensor.
Single rod has a two-in-one spark igniter and sensor. |
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What voltage ratings do hot surface igniter’s come in? |
24 V (pg. 6) and 120V (pg. 26) |
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What can you use to clean a flame sensor? |
Scotch-Brite pads or a 000 steel wool |
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During flame rectification, at what point is the current able to flow through the flame to the flame sensor? |
Current flows when the flame rod is positive. This is because the electrons are able to pass through the flame and into the electron deficient positively charged flame sensor. |
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Why did flame conductivity fail as a flame proving system? |
Flame conductivity uses to 2 flame sensor both of the SAME SIZE so the flame was able to form a bridge between the 2 sensors and pass electrons from the negatively charged terminal to the positively charge terminal and vice versa when the polarity switched EQUALLY. This bridging of electrons completed the circuit and flame was proven. However, the signal returned to the control board was a complete AC signal because the sensors where the SAME SIZE. But if one of the sensors grounded out the controller would still receive a complete AC signal and assume the flame was lit. |
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How big does the ground electrode have to be compared to the flame rod in modern flame rectification? |
The area of the ground electrode must be at least four times that of the flame rod.
This is to ensure that the signal returning is fully rectified. The current flowing when the flame rod is positive will be 4x more than when the flame rod is negative. The returning current will be pulsating DC in effect. |
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How big does the ground electrode have to be compared to the flame rod in modern flame rectification? |
The area of the ground electrode must be at least four times that of the flame rod.
This is to ensure that the signal returning is fully rectified. The current flowing when the flame rod is positive will be 4x more than when the flame rod is negative. The returning current will be pulsating DC in effect. |
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When is continuous trial for ignition not allowed? |
Continuous trial for ignition is not allowed on propane appliances or direct ignition type systems. |
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What is recycling control? |
Recycling control is in the ignition system. That may try two or three times before lockout occurs. Direct spark systems. |
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How hot is a hot surface igniter? |
Approximately 2600°F or 1427°C |
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What is the importance of a connection diagram? |
It shows where the wires go, and the colors of the wires |
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What is the importance of a ladder diagram? |
It shows how the appliance works for troubleshooting |
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What is the importance of a line diagram? |
It shows the location of the components in the unit. |
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If a three pole - one throw (3P1T) contactor has a N/C auxiliary contact attached to it for a crank case heater. How many poles and throws does this contactor now have? Think compressor contactor. |
3P2T Apparently, now that one of the three poles has 2 throws…We now describe THE WHOLE CONTACTOR as having 3P2T??? Blame Dom (the teacher) not me. I cant find a reference for this nomenclature. |
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Break vacuum with dry nitrogen Remove refrigerant Charge system with nitrogen and test for leak |
Tube sheet leak has rust and you will see that in your analysis |
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Tube sheet leak? |
Pull vaccum in barrel and suck in plastic bag |
