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The model # A-VMC18SB & serial # 801kaed00172 condenser unit & the model of the indoor unit is B-VMC18SB comfort aire inverter series. The inside unit runs but the condenser wont run there is power on the outside unit & a code is giving me on the inside unit the code is CH 05 I don't know what that code means i don't have the instruction manual of the outside unit. The outside unit send the power to the inside unit it's 240 volts single phase it's a R410-a refrigerant. Any information that can solve this problem will be helpful.

Posted by princegabito on


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Robert Horton

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Hi, I can tell you this that you may not no, is the condenser gets its 240 volts ac from a 240 volt breaker in your main breaker box, not from the indoor unit. The only voltage that comes from the indoor unit to the outdoor unit is from the thermostat and control board on the indoor unit to operate the low voltage controls on the condenser. I have know idea what this code means either, but there should be a chart glued to the indoor panel telling you what it is. Remove a panel and look for this. You should also by code, have a disconnect box at your outdoor unit that may or may not have 2- cartridge type fuses inside that may have blown. If you can't see them, look behind the plastic cover to see if they are there. Replace them if you are not sure if they are blown. Do these checks, breaker, fuses, and look for a chart that has the codes on it, and you and I can go from there. Please let me know. I will check back in the morning as it is 12:05 a.m. here.Please do not forget to rate me if you have found the problem as I know you will be kind. Keep me posted and I will check in on you.
A/C, Heating, & Refrigeration Contractor

Posted on Sep 12, 2010

  • Robert Horton
    Robert Horton Sep 12, 2010

    Remove the panels at the indoor unit and you will have a chart glued to it telling you what the code CH05 is. Then you will know. This is just a regular central heating and a/c unit . They all are 240 volt, single phase units, the new ones have the R-410A freon and the older ones have the R-22. If you are sure you have 240 volts to your outdoor unit by checking it with a meter, then this code will tell you what the problem may be. You will need to remove the panels to find the chart that tells you. The manual may be tucked inside the indoor unit also, you will have to look. There is a low voltage control on the indoor or outdoor unit keeping it from coming on. Look for this chart or manual inside the indoor unit and let me know.



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