List the operational sequence for the second stage of Figure ...

[washai]

List the operational sequence for the second stage of Figure 39-34. Just list what happens when the W2 terminal is energized.
 
  What will be an ideal response?

Question 2

What is the heating value of grade 2 fuel oil?
 
  What will be an ideal response?

[nickk12214]

Answer to Question 1

The second stage heating thermostat TSH2 closes to send 24 volts from R to W2, energizing heat sequencer HS1, line 18. The HS1 coil is a small heater that warps a bimetal disk to close the contacts after a time delay of 30 seconds. HS1 has two sets of normally open contacts that close after a time delay to prevent the strips from energizing immediately at startup when the compressor and fan motors are drawing high starting amps. The HS1 normally open contacts close, energizing the first heater HTR1and

the coil to the second heat sequencer HS2, lines 1 and 2. HS2 closes its contacts after a time delay to energize the second heater HTR2, line 3. Note that HS1 and HS2 normally open contacts in parallel with the IFR contacts, lines 10 and 12. They insure that the indoor fan motor will operate whenever the heat strips are operating.

Answer to Question 2

137,000 - 141,800

[washai]

Thanks for the timely response, appreciate it

[frankwu0507]

TYSM