No heat with Carrier Gas Furnace - help! Here's the details .......


  #41  
Old 12-15-13, 03:12 PM
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ohms 20k is 0.1 - 0.09 for the spades on the valve control screwed into the gas box . the wires read 0.9 ohm both on ohms 2M and 20M.
 
  #42  
Old 12-15-13, 03:24 PM
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is the valve control switch also referred to as a gas limit switch?
 
  #43  
Old 12-15-13, 03:32 PM
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I only want the valve readings.
 
  #44  
Old 12-15-13, 03:51 PM
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okay, ohms 20k is 0.1 - 0.09 for the valve readings like in your pic. is that good or bad?
 
  #45  
Old 12-15-13, 04:25 PM
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Our readings are very far apart. I am leaning toward a bad valve as well.
The valve that I am reading is a standing pilot model.
Tomorrow I may be able to get a reading from a Carrier 58PAV or a 58RAV.
 
  #46  
Old 12-15-13, 05:13 PM
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I put in a new thermostat and it turns on the heat at least (still no gas and code 21). still only 14 volts to valve control switch...............and it's on all the time with the 14 volts.

Replace Board????????????
 
  #47  
Old 12-15-13, 08:09 PM
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Yes, you definitely need a new board.
 
  #48  
Old 12-15-13, 08:46 PM
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I just checked with Gray furnace man and he says that the gas control valves that use HSI won't give reliable ohm readings because of the electronics inside. so maybe mine is okay. but I'm worried about the 14 volts that have been constantly going through it. I will disconnect a lead for now.
 
  #49  
Old 12-15-13, 08:52 PM
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I'd shut off the gas valve to the furnace or at least turn the blue knob to off.
 
  #50  
Old 12-16-13, 11:09 AM
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is there a connection I can make from com, etc. to the terminals on the gas control valve to test it with 24 volts to know if it's okay before my replacement board arrives? or do you not recommend this?
 
  #51  
Old 12-16-13, 11:12 AM
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do you agree with Gray Furnace Man that it might not be possible to get a reliable ohm reading off of my valve control switch. He says it's because of some of the components inside that have been added inside the limit switch with furnaces that use HSI and not a gas pilot.
 
  #52  
Old 12-16-13, 05:21 PM
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do you agree with Gray Furnace Man that it might not be possible to get a reliable ohm reading off of my valve control switch
I can believe that your valve would have a different reading that the standing pilot valve that I measured.


is there a connection I can make from com, etc. to the terminals on the gas control valve to test it with 24 volts to know if it's okay before my replacement board arrives? or do you not recommend this?


I might jump out the valve but I'm not sure that I recommend a homeowner try it.


It would be much safer not to attempt it.
 
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Old 12-21-13, 04:41 PM
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Hi again! I'm back. I did jump the R to the valve terminal and it works just fine with a nice solid click. so I put in a used z007 board off of Ebay and guess what? Same thing!!! only 14 v going to valve and no increase in voltage when it's time for it to open the gas to the glow plug. what's the chance of this used board being bad in the same way mine is?????

Is this because my com gets 27 volts and not 24 v? is that why my board won't work right or is it just a bad coincidence that I got a bad used board from Ebay?
 
  #54  
Old 12-21-13, 04:48 PM
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you said once that my reading of 27 volt between r and c is good. but could this difference of 3 volts too much be making the board behave like it's shot?
 
  #55  
Old 12-21-13, 06:26 PM
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27 volts is more common than 24 volts.
I wish that you purchased a new OEM (as in not ICM) board.

What trouble code are you getting?
 
  #56  
Old 02-13-14, 10:10 PM
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Thanks Hoiuston 204 for all your help on this and also to Grey Furnace Man. I got the Carrier auth. board as you suggested off Ebay (new) for just 110.00 bucks and now finally have heat again! No more space heaters!!!
 
 

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