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Any one explain to me why this would be the answer? I'm probably over thinking it, but I need an explanation.

Thank you!

The thermostat terminal 1 is the R and terminal 2 is W.  The thermostat would need to close R and W on a call for heat.  If we are reading 24V across terminals 1 and 2 the switch is open.  Either the thermostat is defective or not calling for heat.  If the switch is closed we would read 0V across terminals 1 and 2.

 It also states there's 0 volts on 6 & 7, which would make sense if the break is at the thermostat. If the thermostat was closed, you'd have voltage on 6 & 7.

I think they mean there's 0V when you measure across terminals 6 and 7, which indicates a closed switch.  We would measure 120V from terminals 6 and 7 to ground as that limit is part of the 120V circuit.

Agree with above. Thermostat is a switch. Voltage across a switch indicates its open.
Can I ask what course this is for? G2, G3.....?

Quote from: Admin on April 12, 2015, 03:22:51 PM
I think they mean there's 0V when you measure across terminals 6 and 7, which indicates a closed switch.  We would measure 120V from terminals 6 and 7 to ground as that limit is part of the 120V circuit.

Ah yes, that makes sense. I was looking at it wrong. Now it looks so easy.

This is for G2.

Thanks for all the help.

Question 140... Page 252 of the B149.1-10 states 13.9% for propane. Where does 9.0-9.9% come from? I've looked in all my modules and cannot find that.

QuoteUnless otherwise specified, what is the recommended C02 range for oil to propane furnace conversion?

I have never seen an oil furnace converted to propane, but I assume an in-shot burner would be installed.

You're right, the Gas Code states the Ultimate carbon dioxide (CO2) percentage by volume for natural gas is 11.7% and for propane is 13.9%.

I assume if you were using a propane in-shot burner you would want 13.9%.  I'm not sure why your answer is A. 9.0 - 9.9%.  It looks like someone had picked answer C. 13.0 - 13.9%, but then erased it and picked answer A.

I had picked answer C. But apparently I was wrong when we went over the answers with the teacher. So I corrected it to answer A.