Adding air compressor under seat, in progress...Done!

Thought I'd takes pics of the process I'm using to add a ViAir compressor under the passenger seat. I like how it is out of the way but ready at any time. Downside is, as some have pointed out, that you need to open the door to use it and if it is raining that means a few drops will get on the seat before you swing the door closed to just let the air hose stick out the bottom...heh.

I decided to not use the floor grommet and instead use the one on the passenger side firewall (mostly because the driver side grommet is stuffed full of a 4AWG power line to the 1kW stereo amp under that seat.) Plus the firewall grommets are protected by the hood and won't get mud/water splashed up in them if the rubber seal moves a bit.

I wanted to turn it on and off with a blue lighted switch on the side of the mounting bracket. I got the DesertDoesIt mount and seat jackers for this purpose. Since the compressor comes with a 40A fuse in the factory power cables I figured it shouldn't ever pull more than 40 amps...right?

Since I didn't want the lighted switch to carry the full current I got a 40A relay and wired it all in. Well. It seems that china doesn't rate their relays the way we do in America. Testing prior to bolting everything in (luckily) showed the compressor working for a few seconds, then the relay clicking off for a few seconds, then clicking on again...etc.

So I ordered a 60A (again chinese) relay and hope it will work better. Note that the 40A fuse at the power source didn't pop, so the issue is in the relay. It will be the first item wired into my Blue Sea power center! When I get the relay this week and test it, and if it works, I will finish uploading the rest of the installation and final look.
UPDATE: added final picture after I got everything sorted!

Relay that seemingly didn't work properly:


Power center with wires routed up firewall:


Spot where wires go into cabin:


Inside cab before routing wires under carpet:


To make enough room you must reroute seat wires from under frame to on top of it:


Compressor mounted to the DDI mount:


Final image with seat reinstalled and compressor mounted underneath:



UPDATE: final picture added at bottom. The relay was not the problem, because the new 60A one did the same thing?! Turns out I was stupid and dumb at the same time. The compressor is the "automatic" model, which I later remembered meant that it only runs until the tank is full. Good grief. But at least I can feel good that I did perfect on all of the wiring on the first try.

 

Are you concerned at all about heat? My air cooled portable compressor gets very hot.

 

I would be more concerned about air compressor under the seat.

 

Is that relay current limiting? Usually when a relay closes then opens, it's because voltage dropped below the required potential to hold it shut. Drawing more current than the relay is rated for may also cause it to open by failing it, burning/melting the circuitry inside, but it won't work again after that. If you check voltage at the relay post 85/86 (whichever is on the + side) when switching the compressor on and it falls to 11ish or something lower when it opens, voltage is probably the problem.

 

Thanks for this info, I will check it out. Nothing in the relay packaging says anything about current limiting. Would hate to plug the new relay in and have it do the same thing. Guess I should have had the engine running also, since it had been sitting there playing the radio for several hours while I was working on it...

 

Not really, it won't be running very long and the door will be open for airflow. Plus a lot of others have done this with no problem. I did move the existing seat wiring up out of the way as well. If I think it is an issue (say, smelling burning/melting seat foam) then I can always add an aluminum heat shield over the top of it later.

 

LOL why? I'll be adding an ejector after this...

 

Oh, yeah I bet that voltage was the problem. The draw of those compressors is not small, and a 30 amp draw on a battery that has been draining slowly for a while will easily pull voltage down. I wouldn't expect to run that compressor with the engine off even with a fresh battery, it will drain the battery pretty quick if it's pulling 30 amps and no alternator to back it up.

 

I thinking mostly about cooling for the compressor itself.

 

Hmmm. Hadn't thought of that, maybe I can put a little computer exhaust fan down there also since there's plenty of room and I can drill little screw holes in the mount. Thanks for the idea!

 

Yay I'm done and everything works great! Not worried about the heat since the "automatic" model I have only runs when the tank is nearly empty so duty cycle is very low.

 

Nice. So what was the deal with the relay? Just voltage or was there more to it?

 

LOL well I feel sheepish, there was no problem with it. The 60A one did the same thing as the 40A one, then it hit me that the compressor only "runs" when it has to fill its tank since it's the "automatic" model. Good grief.

 

No worries, that's good news. Just wanted to see if there was something else going on or if it was that simple. Enjoy the compressor!

 

Really cool placement idea. Nice work!

 

tagging for future reference. good job. would you happen to have a parts list?
which compressor, was it a portable compressor, or was it meant to be hard wired? any info helps. thanks

 

Heated seat mods are getting weird.

 

It was the ViAir 400P Automatic. Note the "automatic" which is worth the extra expense. It fills the tank and *then shuts off* thus saving your ears and saving heat generation. They have a version that is built for this but it costs a bunch more so I got this one and took it apart and rewired the switch area to have a modular plug for the power. Then I got a DesertDoesIt under seat mount which is built for the major air compressors, and it fits perfectly (you could easily drill holes if needed). Then I bought some relays off Amazon and used them since I wasn't sure about current draw, and wired it all in. The seat wiring placement changes are important to avoid having wires sitting on the compressor but I think that is detailed in the instructions that come with the mounting panel. Note that it requires a front set of "seat jackers" to lift the seat up a little bit. It works great!

 

I just did this install but did the desert does it mount and single arb under the driver's seat. But now my lane departure and collision system isn't working. Wondering what the hell I did wrong. Followed chloes video pretty spot on any of you guys run into this?

 

Sorry to necro but did you ever figure this out? Inquiring minds want to know...