AC Unit Jumps to 50+ Amps

[astringer32]

Hi Everyone,

We drove our 2018 Era 1,500 miles only to realize the AC unit wasn't working. When plugged in to short power the fan on the unit works, but when you switch it to AC mode, it jumps to 50+ Amps which is when the van auto kills the AC Unit within a second.

I'm no AC expert but it definitely isn't supposed to jump that much when turning on. Does anyone have any ideas what the issue might be here?

Thanks,
Andy

[imnprsd]

My guess is that you lost your motor starter. A motor starter is part of your AC hard start kit that helps your AC to start. And when it's not "in the circuit" your run capacitor can get the job done on its own... and the net effect is that you see your amps go sky high.

Note: The same thing can happen when you are trying to start your AC when the OAT is over 105F.

OP: Here's some questions

* What is your AC type and model number?

* How hot was it outside you you noticed your high current?

* Did you get any of your ACs to start normally?

* And how long do you think your AC was running at 50A?

* Were you on shore power or generator power?

* If you were on shore power are you sure it was over 108V?

* Do you have 2 or 3 roof top ACs?

Here's a video on "in rush" current that occurs when your AC starts. It explains why you need a strong generator.

https://www.youtube.com/watch?v=AwYqeBwpTGw

===

For more information on what a Hard Start Kit is, you can copy this link to your google search bar... and skip to Post #73:

imnprsd Hard start Kit site:winnieowners.com

or you can type imnprsd Hard start Kit into the Winnebago search bar above.

RV sold before 2012 mostly came with basement AC, but the principles are the same.

Note: The repair costs are not that bad, but they will be even less if you know what to do; and if you follow the above threads, you also will not get taken advantage of by a HVAC tech.

Note: If it was really hot outside and this 50A hiccup occurred, then you might try a SPP4E if your start capacitor calls for 88-108uF.

[astringer32]

Thanks Imnprsd. To answer your questions:

The temp outside was about 80 and humid. The AC spiked up to 50A and then died within a second. We were on shore power. It is only one AC roof unit.

Not sure if that helps or not.

[imnprsd]

It does help. I would get up on your roof (if you are safe to do so). Take off the AC cover and do a visual inspection. You might find a leaking capacitor or a burned motor starter (PTC-R). Then just replace your Hard Start Kit or get an SPP4 if your start capacitors are spec'd at 88-108uF.

Note: Finding WSX5 or WSX7 motor starters are hard to find. However, those Supco SPP6 parts are used by all HVAC pros. The SPP4E is probably only available on Amazon; and the SPP4E is a better match with your current Hard start kit, but if you have a weak compressor then the SPP6 maybe a better choice.

OP: Were you able to start your other ACs?

Note: If you find a burned motor starter that is caused by plugging in to low shore power. (Lower than 110V.)