Zinger Lite ZR18BH Fuse #6 question

[vtirocz]

Hi,
I have a 2019 Zinger Lite 18BH model and have an issue where Fuse #6 seems to blow fairly often with no accessories in the RV on. I notice it after I unplug the camper from 110V household outlet and try to use accessories off battery power. I troubleshoot and always find Fuse #6 to be blown. This has happened 3 times in the last 6 months. Camping World did some troubleshooting on it since it's under warranty and simply replaced the fuse with a 15amp fuse (I'm assuming that's what it was built with?).

I reached out to Keystone RV directly and this was their response - they say it should be a 30amp fuse, but to confirm with the selling dealership (not sure why the selling dealership would need to verify what the design is supposed to be??):

" I believe that circuit 6 is the recharge line and I’m showing it’s a 30AMP. Are there spots for 2 fuses at 15amps. If not then I’m not sure why there is a 15 in the 30. I’d recommend to contact the selling dealership on that. I don’t want you to get yourself in to trouble if the information we have on our side is wrong. It may have been changed in production and not updated on our end.

Please do follow up on the inquiry with your selling dealership."

One additional piece of information: I believe the issue I'm having is identical to what's documented in this TSB (not for my model), where Fuse #6 was shipped out from the factory with a 15amp fuse instead of 30amp fuse: https://static.nhtsa.gov/odi/tsbs/20...57855-3763.pdf

QUESTION: Is a 15 amp fuse the correct rating for fuse #6? If others have this model (or similar), could you please confirm? It seems small to me, but that's what it came with. On the circuit board itself (see picture) it says "F5&F6 Position; Max. Rating: 30 amp; For Battery and Slide Out Used". I suspect simply swapping in a 30amp fuse would fix the problem, but want a concrete answer that the circuit was designed for that since it's really the minimum gauge wire in the circuit that matters, which I don't have visibility of.

Thanks in advance!!

[vtirocz]

I've posted some additional info in this thread: https://www.keystoneforums.com/forum...507#post389507

Based on the fact that the wiring from Fuse #6 leaves the panel with 10 gauge wire and connects to battery cable that runs straight up front to the positive cable, I think I agree with the Keystone tech support rep and the unit should have been built with a 30amp fuse in the #6 slot.

If anyone has additional input from what was provided in the other forum, let me know.

[Lloyd]

I read your thread over on the Keystone forum. Seems like you got some good feedback from those guys.

[vtirocz]

Yes! I think it's fixed now, but will monitor to confirm. I really think they inadvertently put an undersized fuse in this location. I wonder how many others were built the same way.

[Lloyd]

More then likely that's the case. You might consider going up in fuse size in steps. It seems the monitoring might be a little safer that way.

[vtirocz]

Thanks for the suggestion. I did consider slowly increasing the #6 Fuse (and might still do that), but based on the Keystone RV tech support feedback and also after seeing the wiring (minimum 10 gauge), I think 30amp is appropriate/safe. Right now I have a 30amp Fuse in and all seems good, but I'm only plugged in at home and not to a full 30 amp service.

[backcountrycamp]

I think this topic is pretty well resolved, but just for the archives... Fuses don't protect devices. They protect wires. You size them specifically to blow before enough current would be running in a wire to make it heat up and potentially melt (or have its insulation catch fire). So if your wire is 10AWG, 30A is indeed the appropriate size.

Here's a table for future reference. This is just a random grab off the Internet. In actuality, wire length is very important. 14AWG can easily carry 30A or more without overheating if it's only 6" long. So take these with a grain of salt - I believe these sizes are for up to 25' runs.

Gauge Recommended Max Fuse Size
00 awg 400 amps
0 awg 325 amps
1 awg 250 amps
2 awg 200 amps
4 awg 125 amps
6 awg 80 amps
8 awg 50 amps
10 awg 30 amps
12 awg 20 amps
14 awg 15 amps
16 awg 7.5 amps

[Burnsdav]

I have a 2020 18bh and it does the same thing. I read the keystone forum discussion on this so no I will pull the panel to check the wire size and color then follow it out. Mine has the same 15 amp fuse in spot #6.

[vtirocz]

Originally Posted by Burnsdav

I have a 2020 18bh and it does the same thing. I read the keystone forum discussion on this so no I will pull the panel to check the wire size and color then follow it out. Mine has the same 15 amp fuse in spot #6.

Just a follow-up to my prior post since it's been a few years: Putting the 30 amp fuse in the #6 spot fixed the issue for me. I'd say it was definitely built with the wrong fuse (similar to the attached TSB).