I just bought a brand new XP13000HXT generator from Duromax. It is easily able to start up on gasoline or propane, but will not start using natural gas. I’ve already checked the gas line pressure and the ability to support the 225,000 BTUs for this generator, and I’m using the correctly sized gas line supplied by Duromax, along with the Duromax fittings. Some pretty exhaustive Google searches have turned up nothing… Apparently nobody has this problem? Here’s one for the problem solvers! I will try contacting Duromax during their normal business hours.
Here’s a video giving all the details so you can see the setup, etc.
Video
I've looked through all the posts (as of 1/11) and the video. I don't have experience with these "from the factory" tri- fuel units like the XP13000HXT, but I've set up a couple gens with conversion kits and run them on NG. Here's a couple comments and questions that may help the troubleshooting. I don't have any specific suggestions.
1. I don't have an NG meter, but over the years at three different houses, I noticed I could easily block the NG gas flow by simply putting a thumb on the open pipe feeding appliances. That may be a good quick test of a too high gas pressure; if you can't stop it easily; its too high.
2. The regulators I got with my NG conversion kits seem to be designed such that they completely block the flow of NG to the engine if there is no vacuum provided by the engine. (I don't know if they also serve as a pressure reducer). This blocking is a safety mechanism; without that blocking, an engine that died would still get raw NG pushed into it and would be a hazard.
3. These regulators have a primer button to allow NG into the feed pipe just before starting so that NG is available to start the engine; at that point vacuum is generated which hold the regulator valve open
4. At 0:39 of the video is a picture of the gen panel. Notice that in "Step 1 select gas type", NG is alone as one choice while propane and gasoline are grouped together as the second choice. Does this choose the "porting" some of you have talked about? (Step 2 choices have NG and propane together as a choice and gasoline alone. This must simply be choosing the gasoline tank vs. the front vapor pipe as the source).
5. In the video, when NG is tried, the starter does not run continuously; is the purpose of pausing to allow flooding to dissipate or is that something to protect the battery? Would that also happen on the gasoline setting if it did not fire up immediately?
Since high NG pressure is not available to the customer, and these small engines are designed to feed themselves via vacuum, not force-fed by gas pressure, I'm thinking the problem doesn't have anything to do with the gas supply being too strong, although a stuck open primer mechanism could, perhaps, cause issues.