Onboard Air Compressor

[TwoElkhounds]

Kevin, you neglected to mention the most important aspect of this project--now you can power an air horn!

You mean TRAIN HORN!!! You got to go with the real thing!! Nathan or Leslie train horns!! Easily accessible on ebay for a reasonable cost. Nathan's are better on air, Leslie's are air hogs and are bigger and harder to fit on the truck. Both sound amazing.

DAN

[howson]

One other thing . . . I always make sure that I have the truck running when I do this for best voltage at the compressor.

OK, so here's the plan.

1) I'm going to wire in the hot side of the WirelessOne harness to upfitter switch #6 . Upfitter switch #6 's circuit is protected by a 40A fuse. The VIAIR has a 30A inline fuse. I'm thinking it is prudent to replace Ford's 40A fuse in the upfitter box with a 30A fuse. I'm going to leave VIAIR's original fuse inline, too. (The upfitter fuse is near the battery, the VIAIR's is near the compressor in the truck's bed.)

2) I'm NOT going to wire in the Ignition Source Connection wire to the brown Upfitter RUN/START OUTPUT wire. I don't want the compressor running unless I specifically turn on power (upfitter switch 6.)

3) I agree with your thought process about having the truck running for max voltage so I'm not going to make Upfitter Switches 5 and 6 "Hot-at-all-times".

Any thoughts/comments?

BTW--what a pain trying to find nuts to install VIAIR's "emergency" schraeder valve on the side of the hitch! The valve has 8mm thread with a .75 pitch. Couldn't find that style nut in a local store. I had to order from Amazon. (!)

I also discovered the black hose is 1/4" OD and 1/8" ID. Took me a bit, but I found an adapter at Lowes so I can incorporate the VIAIR and a filter into my setup. I haven't tested it yet...hope it all works together! (I'll post the complete setup when I'm done with the install.)

[FT4NOW]

OK, so here's the plan.

1) I'm going to wire in the hot side of the WirelessOne harness to upfitter switch #6 . Upfitter switch #6 's circuit is protected by a 40A fuse. The VIAIR has a 30A inline fuse. I'm thinking it is prudent to replace Ford's 40A fuse in the upfitter box with a 30A fuse. I'm going to leave VIAIR's original fuse inline, too. (The upfitter fuse is near the battery, the VIAIR's is near the compressor in the truck's bed.)

2) I'm NOT going to wire in the Ignition Source Connection wire to the brown Upfitter RUN/START OUTPUT wire. I don't want the compressor running unless I specifically turn on power (upfitter switch 6.)

3) I agree with your thought process about having the truck running for max voltage so I'm not going to make Upfitter Switches 5 and 6 "Hot-at-all-times".

Any thoughts/comments?

BTW--what a pain trying to find nuts to install VIAIR's "emergency" schraeder valve on the side of the hitch! The valve has 8mm thread with a .75 pitch. Couldn't find that style nut in a local store. I had to order from Amazon. (!)

I also discovered the black hose is 1/4" OD and 1/8" ID. Took me a bit, but I found an adapter at Lowes so I can incorporate the VIAIR and a filter into my setup. I haven't tested it yet...hope it all works together! (I'll post the complete setup when I'm done with the install.)

Some thoughts and comments. Are you sure the VIAIR is a 30A fuse? Mine is 40A. Also, have you actually seen the wires available for the upfitter switches? I know your truck is a model year newer and could be different, but those wires are small, at least on mine they are. I know they already have fuse protection and are on a relay, but it might be a better idea for you to run the compressor off a dedicated relay off the battery with proper size wire and put your 40A fuse there, and use the upfitter switch to close the relay. I did it that way for some rear LED light bars I put on, I just dont see how the wires Ford provided are adequate for their rating.

Sent from my SM-G950U using Tapatalk

[GeoffnCheri]

^^ Following^^

[Cate&Rob]

Hi Howard (@howson)

Not having "upfitter switches" on our F150 . . . and wanting to keep all the wiring at the back of the truck, I spliced into the trailer battery charging wire to the 7 pin connector. This is wired and fused by the truck at 40A and then in the added wiring to the VIair compressor at 30A. Seems to work well so far.

An interesting "back feed" does occur. If the truck is turned off but the trailer is still plugged in, the truck battery is disconnected from the 7 pin connector but the trailer batteries will still power the compressor in the truck.

Rob

[howson]

Hi Howard (@howson)An interesting "back feed" does occur. If the truck is turned off but the trailer is still plugged in, the truck battery is disconnected from the 7 pin connector but the trailer batteries will still power the compressor in the truck.

Have you considered inserting a diode into the circuit?

[Cate&Rob]

Have you considered inserting a diode into the circuit?

A diode could stop this back feed . . . but, this would have to be a 40A diode. This is not really a problem, because it is easily solved by unplugging the 7 pin connector from the trailer whenever we are parked (which I usually do anyway).

Rob

[howson]

Are you sure the VIAIR is a 30A fuse? Mine is 40A.

Yes!

Also, have you actually seen the wires available for the upfitter switches? ...those wires are small...I just dont see how the wires Ford provided are adequate for their rating.

I'll see if I can figure out what's exactly there and report back when I get the wiring installed. I'd be more concerned about an always-on, heavily loaded circuit (like the refrigerator power-from-inverter project I'm planning).

According to VIAIR's website, the 450P-RV's max current draw is 23A. If Ford's circuit, specifically designed for add-on components and fused at 40A, can't handle a relatively short-term 23A...that would be a major problem!

But thank you for the questions--made me go back and re-look at the circuit and double-check.

More than 90% chance of rain today so likely won't make any progress.

[howson]

I know your truck is a model year newer and could be different, but those wires are small, at least on mine they are.

Thought you'd be interested--I checked the wire coming from upfitter switch/relay 6 and it is 8ga (rated to 40a).

[howson]

The power wire on the WirelessOne's harness is protected by a 15 amp fuse and the small compressor that came with the WirelessOne system has a label that shows it pulls 12 amps. That got me looking at the wiring harness I was planning on hooking up to the VIAIR.

I have a gauge that showed me the red power wire on the WirelessOne's harness is 12ga. 12ga has a max current carrying capacity of 20 amps. The 450RV-P (per VIAIR's website) can pull 23 amps during normal operation and it's wiring is fused to 30 amps. The 12ga wire on a 30a fused circuit is an issue. It's not that the truck will explode in a fireball mushroom cloud when I turn on the VIAIR (if connected to the WirelessOne's harness) but over time and with a lot of use something could go very wrong.



So I'm going to use the WirelessOne's compressor and hook it all up as designed by the OEM. I'm then going to mount my VIAIR in the truck's bed and wire it through the Upfitter Switch.