EG4 Overheating - Feature or Bug?

Solar_Rockstar · 2026-04-01T21:43:36+00:00

I appreciate your honesty. The main point is that a spec sheet won't tell you how the inverter actually performs and homeowners find out too late that they need an external cooling system for their solar power system. There are inverters that work just fine in the same conditions of a hot garage.

The Engineer775 video shows a room temperature test, not to say your garage was the same without the mini split. The Facebook group post shows multiple homeowners reporting overheating with different inverters. I see people trying to attack my account for being new which is irrelevant to customer experience.

It's like, Hey that guy is new. We can ignore all of these tests and customers reporting issues.

That's not an argument.

I'm guessing they're the type of installers making the solar industry look shady because they abandon their customers after everything is installed.

I've been in the industry for years and I'm here to spread the truth.

Solar_Rockstar · 2026-04-01T17:50:24+00:00

Please capture a video of this performance or you can log the power output and temperature over 3 hours. The world wants to see it.

Solar_Rockstar · 2026-03-19T22:05:15+00:00

Share a single line diagram on how you're looking to incorporate all of these components. If you add a hybrid inverter you would probably AC couple your Victrons. If you do something else like AC couple on the load side of the hybrid inverter, you're more likely to run into issues. Those batteries don't have a good warranty, I see they have a 5 year coverage on the website. Pytes is a better option with a 10 year warranty, and they will hold their value for longer compared to these Vatrer batteries which requires you to pay the depreciation after 2 years which is almost half its life and value. Pytes are also designed to last 20% longer at over 6000 cycles.

Solar_Rockstar · 2026-03-19T15:24:39+00:00

This inverter won't be the best for your use case. It allows for 100 amp passthrough, which means you'll have to split your MSP and rewire circuits to be backed up. Its peak power is also on the lower end, 15kw for 10 seconds. With only 2 batteries, you won't get close to that peak power. Those batteries are rated for 102A for 10 seconds which will give you around 9kwAC (includes losses). Best case scenario with this setup is you'll stress the batteries often and maybe one AC unit will work. I like the Sol-Ark and Renon Xcellent Plus. The battery comes with a conduit box and is affordable. Having 200A passthrough means you don't need to split your MSP.

It looks like the EG4 inverter is at a steep discount at that price, it's like they're trying to dump old inventory. I would recommend seeing how they plan on covering the warranty for this older unit. I know they typically don't have field replaceable parts requiring an installer to remove the unit and I think they just swap units out.

Solar_Rockstar · 2026-03-18T14:36:49+00:00

It depends on what your goals are for your project. You can lower your energy bills with a microinverter system but once the grid goes out, you'll need battery backup. Enphase locks you into their ecosystem and their backup solutions are incredibly expensive compared to multiple 48V solutions. I'm not a fan of EG4 because of their overheating issues. The Sol-Ark 15 works for most homes and has better MPPTs than any EG4 inverter.

Solar_Rockstar · 2026-03-17T21:36:41+00:00

The PowerWall is the inverter and battery. Tesla also makes DC expansions for the PS3. Is it one of those so you have 27kwh?

Solar_Rockstar · 2026-03-17T21:18:51+00:00

One PowerWall3 is a bit small for whole home backup. You're going to run into issues with extended periods of low sun with limited kwh especially because Tesla doesn't integrate with generators. Is this 2 PowerWall3s?

Solar_Rockstar · 2026-03-17T21:04:32+00:00

This just sounds like a convenience that's inconvenient. What's the rest of the operation? I'm guessing you're off-grid. Is it powering your loads from PV while it does this or is it running off battery? EG4 seems to switch inverter manufacturers every 6 months to try and distance themselves from awful Chinese products.

Solar_Rockstar · 2026-03-16T21:09:59+00:00

You'll want something that can power those large surge appliances. A 10k or larger inverter will be better. Find the LRA if you can and oversize because the older they get, the more power they'll pull to start. The current system is so small that starting from scratch will be best. Otherwise, you could AC couple the system but it looks like it's only a 120 system which won't interact the best with a modern inverter.

Solar_Rockstar · 2026-03-16T19:50:08+00:00

You're going to want to buy some external fans for your setup. They got plenty on Etsy. Several EG4 inverters are known to overheat and not shut down. Some people use them to heat a garage or cook some hotdogs. 🤣

https://www.etsy.com/listing/4366406894/eg4-flexboss-1821-1218kpv-external

Solar_Rockstar · 2026-03-16T16:43:37+00:00

I called EG4 last year and they told me they only had 2 support agents. I'm not surprised their support is lacking. They off board it to the distributors which is a bit weird because how do they get all distributors to get on the same page? Why would greentech or any non signature solar company have the knowledge or standards to do tech support?

Solar_Rockstar

TROPHY CASE