The device used to prove that a burner flame is present in a furnace with hot surface ignition is a ...

The device used to prove that a burner flame is present in a furnace with hot surface ignition is a _____.
 
  a. thermocouple
  b. glow coil
  c. flame-sensing rod
  d. bimetal switch

---

[Ques. 2] The minimum voltage reading you should expect when testing a thermocouple under load is _____.
 
  a. 24V
  b. 10mV
  c. 18V
  d. 30mV

---

[Ques. 3] Which of the following is not part of the operating sequence of a natural-draft furnace?
 
  a. The draft inducer starts on a call for heat.
  b. The controls prove that the pilot is lit.
  c. The gas valve energizes and opens.
  d. The fan switch starts the blower.

---

[Ques. 4] What occurs after the pilot flame is proven on a gas furnace or boiler that uses spark ignition to light the
  pilot?
 
  a. Sparking ceases
  b. Burners light
  c. Inducer starts
  d. Flame is sensed

---

[Ques. 5] An evaporator pressure regulator is typically _____.
 
  a. controlled by an On-Off switch
  b. controlled by a programmable controller
  c. a self-contained device
  d. required on all domestic refrigeration systems