Viair 400P-RV and 450P comparison
I finally gave in to find an easy solution to topping off my tires without turning on the engine. I have been reading good reviews about the viair 12 volt portable compressors and wanted to give them a try. The one problem was, I could not decide which of these two models would work best so I purchased both to test and would return the one that does not perform best.
Here are the specs for the two models:
Model 400 P-RV Automatic-
Duty cylce = 33% (can run for 10 minutes then must rest for 30 minutes)
CFM = 2.54 CFM
Advantage = greater CFM
Disadvantage = shorter duty cylce
Max amp draw = 30 amps
Model 450 P Automatic-
Duty cycle = 100% (can run continuously without stopping)
CFM = 1.66 CFM
Advantage = 100% duty cyle
Disadvantage = Lower CFM
Max Amp draw = 20 amps
(note on amp draw and compressors: the more efficient the compressor is the lower the amp draw is, so the lower number here is better than a higher number)
To be clear, I will never use this compressor to fill a flat RV tire, only to top them off with 5 to 10 psi. I needed something to reach 120 psi without struggling. My main concern and question with the 450P was would it take a ridiculous time period to top off a tire compared to the 400P RV.
I purged one tire to 117 psi and clocked the time to fill this tire to 122 psi. The ambient temperature was 75 degrees Fahrenheit
The 400 P-RV took 1 minute, 35 seconds.
The 450P took 1 minute, 55 seconds.
As it turned out the difference in time was not too significant. My choice was to keep the 450P in order to have the 100% duty cycle and will be sending back the 400P-RV.
I was particularly curious about the performance of these two models when I first watched a video recommending the 400P-RV from the RV GEEKS. I wonder if they ever tested the 450P model.
I hope this information is helpful to some and look forward to hearing your input and opinions on this subject.
Stuart & Leslie
08 Holiday Ramb Navigator, 45 ft, Cummins ISX 600, 2014 Cherokee Limited, Cashmere. Roadmaster Sterling, SMI Airforceone. Full-timing since May 2014