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A/C electrical question

June 16, 2017, 05:45:55 pm

Noticed the front A/C sounded like the compressor was trying to start but did not. Looked at the panel in the coach and noticed the inverter came on when it was trying to start. When it failed to start  everything back to normal. Tried it with the generator on and same thing. My question is ,does the inverter try to "help" when there is a high load requirement?  Is there something else going on here?

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Re: A/C electrical question

Reply #1 – June 16, 2017, 06:11:53 pm

NO, the inverter should not be involved. That doesn't mean that someone has not done some "creative" wiring.

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Re: A/C electrical question

Reply #2 – June 16, 2017, 06:20:04 pm

Well that's what I thought . Never seen it before but electrical is not my strong suit. Fortunately I am scheduled in next week to have both units replaced. This is why I've always wanted a 42ft. 3 A/C's 

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Re: A/C electrical question

Reply #3 – June 16, 2017, 06:34:00 pm

Sounds like you may have a bad capacitor in the A/C.  Not expensive or difficult to replace.

Unrelated to your "inverter kicking in".

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Re: A/C electrical question

Reply #4 – June 16, 2017, 06:38:59 pm

That's what it sounds like,but I just replaced both of them on that unit about a year ago so it was was not he first thing I thought about . I failed to notice what the voltage was when this happened. 

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Re: A/C electrical question

Reply #5 – June 16, 2017, 06:47:16 pm

No question, low voltage will cause the same symptoms.

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Re: A/C electrical question

Reply #6 – June 16, 2017, 06:55:50 pm

Brett seems to have hit the main point, but...

With your comment about the inverter I was wondering if you had a new hybrid inverter/converter that might being trying to supplement a low 120 volt load with battery power.

How are the ambient air temps where you are?  We get rolling brownouts here when the temps soar due to an increased demand for air conditioning use.

Chris

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Re: A/C electrical question

Reply #7 – June 16, 2017, 07:08:02 pm

I do NOT have a hybrid system. That's why I was so surprised to see it. I am assuming at this point that it was a capacitor.

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Re: A/C electrical question

Reply #8 – June 17, 2017, 12:02:29 am

What model inverter/charger do you have, and what indication do you have that the inverter automaticly turns on?

Does turning off the inverter switch change what you see?

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Re: A/C electrical question

Reply #9 – June 17, 2017, 10:03:21 am

If you have two identical rooftop units and one of them works, swap the capacitors and see if the problem goes with the capacitors.

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New A/C's

Reply #10 – June 23, 2017, 06:54:55 pm

A quick update on the replacement of both my original equipment air conditioners. We are pleased so far. The  new units seem  to be more efficient i.e. they don't run as long and the temperature "feels" more constant thru out the coach.  The big question everyone asks is "Are they quieter?"  Well, yes and no.  I also replaced the thermostat and it looks at the difference between interior temp and requested temp and adjusts the fan speed accordingly. So initially it is "loud" (fan high) but after the coach cools and it cycles, it is "quieter" (fan low). Install went smoothly and quickly.  Of course all these comments are purely subjective on my part,  your experience my differ.  At this point I feel that it was money well spent.

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Re: New A/C's

Reply #11 – June 23, 2017, 06:59:30 pm

Please post what the old units were and what you went to.

Thanks.

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Re: A/C electrical question

Reply #12 – June 23, 2017, 07:00:31 pm

[merged original topic and separate follow-up into one topic]

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