How long to recharge a peak portable power system 450 plus

Red light should be on, with all switches (FRONT and BACK) SET to O when charging

I doubt it. Are you sure it is the compressor itself or the motor that drives it? And then a good chance the power to the compressor has bad connections, and perhaps a bad switch. It may cost more than the entire unit.

There is not such a setting , Low power will show amber colour .

Cueck thebattery. It has to be replaced if thevoltage under load ie too low.

Rich

Won't charge, what should I do ?

The motor that drives the compressor is fine. I think you will find that the compressor itself is kaput. This was true in my case.

There is a charging port on the front of the unit next to the LED work light.
The wall charger it came with, is a 12VDC 500ma.
Positive center coaxial connector.
Radio shack usually can match the unit if you bring it in to them.
My charger was pouch Velcro-ed to the unit.
Kings Model KU3B-120-0500D

The internal battery may be too old to be useful any more.

After searching the internet for a ph number for Peak power I finally found the web.
http://www.peakauto.com/contact/site.
phone 800-323-5400
If the part department doesn't have the answer ask to be switched to tech support.
They were able to provide me with the part numbers I need for new wall supply cord and an DC adapter for the car.
My jump starter is no longer made...

Do I have to recharge it regularly before the battery goes down to uncharged. I'm talking abt peak 450 plus