Girard Tankless blowing PANEL fuses

[InMyImage]

After a lot of running in and out and around our 2018 North Point 5er, I’ve narrowed down an issue with a blown (blowing) 15a fuse in our main electrical panel.

The fuse is labeled for our Main control panel, main thermostat, water pump and water heater.

All in all there are a lot of possible switch combinations required to narrow down which device is the issue and the winner is our Girard GSWH-2 tankless water heater.

Fortunately I keep an assortment of spare fuses on hand since we are full-time but went through a dozen trying to chase this down.

Issue is that anytime the water heater is turned on, regardless of whether any of the other items are on or off (except the main control panel of course) it immediately blows the fuse.It also doesn’t matter if shore power is on or off.

Before I start burning through the packs of fuses my wife is picking up, anyone have any solid ideas? It just takes turning on the switch on to blow the fuse so it would be helpful to focus my attention if possible.

Note that the switch fuse in the water heater is fine.

[JFlightRisk]

We don't have one, and I'm not familiar with the inner workings, but my first thought is a dead short on a power wire.

If you don't already have this, here's a Girard technical manual. It may or may not help, but it's all I've got for you.

https://www.rvupgradestore.com/v/vsp...e%20Manual.pdf

[InMyImage]

Thanks, that’s my thought also but figured I’d fish for other ideas too.