Viair pressure switch: HB Follow Up Needed

Hello Everyone! Just got the invite to the forum, so I guess I’ll make a post.

I have a Viair compressor and pressure switch on my PU, and the first pressure switch (which came with the kit) lasted less than a month. Then I bought the updated version, which included the built in relay. That lasted another month.

I took the second one apart (it was built quite well!) and saw some moisture in the grey box, but for some reason the pressure switch failed and would not open.

I am on my third pressure switch assembly, and I put some goop type sealer on the seams of the switch box, and around the wires that go into it. I’m not sure that was the problem, but I wonder if I am the only one who has had issues?

The entire assembly is built very well, I can’t figure out why it would quit in less than a month.



No troubles from mine. The standard switch or the one with the relay.

How is the pressure switch port oriented?

Port upwards?

Port downwards?

Port sideways?

Did you also check the relay to make sure that it wasn’t fried?

I burnt up my pressure switch on my 480s as well… I’m wondering if I should order a new one or not, cuz right now I just bypassed the pressure switch and just use my toggle switch to kick them on and off whenever i need air… Ive gotten really good and knowing when to kick them off at too… :smiley:

Were you using a 90111 ? If not, were you using a relay or sending full current through the pressure switch?

Unless you’ve got a gauge you can look at (and trust) - I’d advise getting another switch on there pronto!

no wasnt using the 90111… that doesnt come with the 480s…
And no didnt have a relay, just sent full current to switch… There was no relay with the switch it came with…

Wanna guess why you fried your pressure switch? They’re rated for about 20 amps… you had 40 going through the pressure switch my friend…

So the 480 compressor kit… which both compressors give out 20amps… which makes 40 amps… and u only give a pressure switch of handling 20amps and no relay with that switch… :confused: :confused:

VIAIR 480C Dual Performance Value Packs come with a properly rated 165/200 PSI pressure switch AND two relays specifically for this purpose…

Besides the 480C, 380C, 400C & 450C Dual Packs, pressure switches & relays are sold separately. As it is, VIAIR is the only Manufacturer offering Dual Packs, much less supplying the pressure switch and relays at no additional cost.

aight well i have the one relay i forgot i do have that in it…

Well maybe you fried the relay then… The pressure switch might still be good.
With a toasty relay, you wouldn’t know if the pressure switch is any good unless you test the switch.

I tested the switch, its dead…
and relay is still good cuz i can still turn the compressors on after i rewired them to a toggle switch…

i wanted to order this from SD. but they always sold out

That’s because SD no longer buys direct from us. Get them from Matt… I’m sure he’s got some in stock…

Oh Matty… where ya’ be?

Hit me up when u read this then matt…

Hey: Thanks for the reply. I have a 90 degree fitting on my pressure switch now, so that it points up. I did put some extra sealer on the top around the switch, and now on the side around the grommet where the wires come in. The second one I had (with the relay) was mounted the same way, but there was moisture in the box. The relay worked fine, the pressure switch failed.

The first one, the pressure switch was horizontal, and there was no relay. It was sold to me as a kit that way.

The current one has worked now for a week, we’ll see what it does.

thanks in advance for your help!