Water in OpenEVSE kit enclosure?


I have had my OpenEVSE kit mounted on the wall for a few weeks now and I have done a good number of successful charges with it. I bought an ESP32 Ethernet Gateway upgrade and was about to install it but after opening the OpenEVSE up, I was a bit distressed to discover water inside and some of the components were showing signs of corrosion / rust.

In another post, I mentioned that I wanted to use rear cable entry. It is very hard to work out where water has come in - some of it looked like it had evaporated and condensed again. But my instinct is that it didn’t come in through the rear - which had a lot of silicon sealant round it.

I am wondering if it came in around the LCD window. I removed the LCD and screwed it back on again, and tightened it as best I can - but the instructions do say to not over-tighten. How tight is tight-enough and how tight is too-tight? Since I tightened it, is has rained again and no-more water seems to have got in but it does worry me.

Has anyone else had problems with water?

The LCD is mounted on the inside of the case - there should be no way for the water to get in that way, the outside is just a sheet of plastic. Unless there is damage.

Do you have a push button?

I have a v5 kit from 2018, not the latest v5.5 kit. There is a cutout for the LCD screen, 4x screw holes and a hole for the button.

When it rains I have seen water collecting on the ridge of the LCD screen opening - seems an obvious route for water to then get into the case. I am starting to think that this is why the case design changed :pensive:

Importing a new official enclosure from openevse.com would be £72.00. I am wondering about rebuilding it in a generic IP rated enclosure with a clear front instead.

Ah, sorry, I mistook you for someone who bought a kit recently.

Is there a bit of clear plastic above the screen? I seem to recall it coming with one, perhaps I am mistaken. I can’t quite make it out in your photo. That cover could then be beaded into place with silicone.

Fwiw don’t use acetoxy silicone for sealing electronics.

The fumes given off during curing are acetic acid and will corrode things.

1 Like

Fwiw don’t use acetoxy silicone for sealing electronics.

Thanks Marko! Sadly some parts are looking pretty corroded due to water damage.
Can you recommend an alternative flexible sealant? Neutral Cure Silicone?

Unsure. I remember destroying things with vinegar fumes a few times until it clicked what was going on (indoor items) as a kid!

1 Like

The kit came with a perspex window and a piece of foam to act as a seal:

I have bought this little tube of “natural cure” silicone:

So I am going to try replacing the foam with a bead of silicone around the perspex.

Thankfully it has been very dry recently but I want to get this sorted out before it starts raining this weekend.

That sounds like the stuff!

Alcohol fumes aren’t going to corrode things the way that acidic fumes (now sealed into an enclosed space) do. :slight_smile:

Thanks for workign out what to Google for!


Just a followup to say that I think the natural cure silicone sealant has been successful.
I put a bead around the edge of the screen, the button, screw holes and screw heads. The small tube/nozzle made application pretty easy:

We have had some heavy rain since I did that and can see how water pools on the lip of the screen:

I have opened the enclosure up a couple of times since and not found any water in it since then :tada:

The corrosion is basically just in two places:

  • On the push button
  • On the 40A mains contactor

I am not sure it is bad enough to need replacing but it is fortunate that both of these are relatively cheap components. I have added a 100g bag of silica gel to absorb any moisture trapped in there.

Hopefully the problem is now solved but still considering replacing with a different enclosure.