Living with the DuroMAX XP9000iH

[Symbioquine]

Some things I've learned about the DuroMAX XP9000iH - hopefully some of this will help other folks:

Similar Generators

This generator is very similar to the following generators which can be used (with a grain of salt) as a reference when looking for helpful reviews, alternate manual descriptions, and parts/wiring diagrams.

• Predator 9500 Inverter Generator
• GENMAX GM9000iED
• TOMAHAWK TG9000i

Fuel Solenoid & Hidden Fuses

• If used regularly on propane, the fuel solenoid will burn out since it isn't rated for continuous duty (part claims 8 hours duty cycle, but realistically its days are numbered regardless in a hot vibrating engine compartment)
• When the fuel solenoid burns out, it behaves like a serious short and blows a little glass fuse (F15AL250V) behind the front panel (where all the plugs/indicators are)
• There are three such little glass fuses (of different ratings) in inline holders behind the front panel which seems like one of the less user serviceable places on the generator
• The fuse that the fuel solenoid causes to blow also means the whole front panel ends up unpowered - making the whole generator look dead
• DuroMAX's support line didn't know want or know how to walk me through even that level of troubleshooting so they sent me a whole new generator under warranty - I don't feel bad about this since I basically begged them to help me troubleshoot the one I already had and cumulatively spent more than an hour on hold
• With a dead fuel solenoid, this generator can still work on gasoline just by unplugging the fuel solenoid and replacing the blown fuse
• The fuel solenoid can be replaced with a motorized ball valve which should have a much longer service life - don't bother trying to get the barbed elbows off the original solenoid since they used some crazy locktite seal stuff and there's no place to put a wrench on the solenoid, instead just get these ones to go with the motorized ball valve linked above
• I'm still experimenting with the motorized ball valve strategy above. The main downside seems to be that it is a bit slower than the fuel solenoid which can allow a tiny amount of fuel to flow after it normally would, resulting in a backfire during normal shutdown

CO Sensor

• The CO sensor is very sensitive and is inside the case of the generator with the engine - any wind or attempt to shelter the generator from the wind/rain will almost certainly cause nuisance tripping of the sensor
• Unplugging the CO sensor does not prevent the generator from starting, but it does not operate normally - the oil warning light comes on and the engine runs in a weird surging version of the low idle
• I'm experimenting with operating the generator with the CO sensor removed by tying the green/yellow striped wire with the white wire that lead towards the area below the starter on the engine as shown on this video
  
  • (Please don't lecture me about the safety risks of doing this: The generator will always be operated in an outdoor enclosure away from people. It is too loud to comfortably stand near under load. We have CO sensors/alarms in our nearby living spaces. I intend to label the generator clearly to indicate that it does not have a CO sensor.)
  • Somewhat related: https://diysolarforum.com/threads/2021-honda-generator-carbon-monoxide-indicator.25808/
• I don't know whether the low oil shutdown is still functional in this configuration
• Instead of cutting the wires as shown in that video, a replacement plug can be made that shorts the two relevant pins and leaves the rest unconnected. I found that the connector was the same as one from an old computer power supply board;
  

Efficiency on Propane

See https://diysolarforum.com/threads/how-efficient-is-your-generator.50418/

Handle Swap

The generator has two kinds of handles, the horizontal bar handles which are located on both ends of the generator and the folding ones that are bolted on to the horizontal bar handle on one end of the generator.

The folding handles can be moved from the back end of the generator to the end with the front panel. This is useful if you're storing the unit in a tight space, but still want access to the front panel - for example to plug in the battery maintainer.

I saw one Youtube comment that referred to moving the handles by drilling new holes in the other end's horizontal bar handles, but I can't recommend that strategy. The horizontal bar handles are interchangeable, but not identical. The back end has a shorter foam pad on the horizontal bar handle that fits between the bracket for the folding handles, but the corresponding foam pad on the front horizontal bar handle goes the full length. I'm pretty sure the bracket for the folding handles wouldn't fit over the foam pad nicely, and it would leave the rear handle with some unnecessary holes and a short foam pad. It's better to also swap the horizontal handles as part of moving the folding handles to the front.

Moving the handles from one end to the other doesn't require any actual modifications to the hardware, but is fairly involved because you have to take the wheels and all four clam-shell sides off the generator. Once that's done, it is simply a matter of removing the 4 bolts that hold the folding handles on, unbolting and sliding the two horizontal bar handles out and swapping them, then re-attaching the folding handles on the front of the generator.

When taking the clam-shell sides off the generator, make sure not to lose these little clips;



Future Possible Parts

When the fuel solenoid issue happened, I was worried that it might be one of the main boards (control or inverter) so I spent some time looking for possible replacement parts.

One part that looks very similar is the inverter board for the Predator 8750 - I haven't tried this yet, but I'm willing to bet it's probably the exact same part...

From Listing	In Generator

Helpful Reviews

 

[Symbioquine]

Update: Added a section to the original post with info about swapping the handles

 

[Symbioquine]

CO Sensor (continued)

• It turns out that the "new" replacement generator DuroMAX sent me under warranty is actually 10 calendar months older (2021/06/01 vs 2022/08/02) than the first one I got. Interestingly, the CO sensor modules are different between the two generators. The mid-2022 model is what I described above, whereas the mid-2021 model has a 6 pin connector and a slightly different looking module;
  
  
  
• The same power supply connector can be made into a dummy receiver like I described before, but the pins that need to be shorted are different. This is what I did since I already had two that I'd cut out of an old dead PSU.
• Actually, it looks like a 6 pin PCIe power socket would be an exact match for the mid-2021 CO sensor cable. Whereas the mid-2022 CO sensor cable is the same as a 8 pin CPU power socket.

 

[50ShadesOfDirt]

Really nice work ... thanks for all the updates!

I ran duromax non-inverter for a long time, but have since switched to Westinghouse wgen9500df (also non-inverter) ... this gets me much automation capability, as these have the smart port, auto-choke, remote start fob, etc.

The inverter-gen lineup has always been too much complexity in too little a space for me (in a rural location); if I can't fix it, it doesn't do well on my site. The control board has always seemed an iffy (expensive) proposition as well, as these things are so potted that they aren't fixable ...

I hope "repairability" concept comes around ...

Again, nice write-up!

 

[Symbioquine]

Thanks @50ShadesOfDirt!

The inverter-gen lineup has always been too much complexity in too little a space for me (in a rural location); if I can't fix it, it doesn't do well on my site. The control board has always seemed an iffy (expensive) proposition as well, as these things are so potted that they aren't fixable ...

I hope "repairability" concept comes around ...

Yeah, I'm hoping that the large volume of similar/identical generators (especially the HF Predator) out there leads to enough grassroots DIY/repair documentation in the wild for me to keep mine running. (I guess we'll see ?)

Worst case, the platform, engines, and generator heads should be re-usable - even if the inverter/control boards fail and aren't replaceable...

I need the inverter style generators because I have sensitive electronics and my generator-driven battery charging is via my inverters so when I'm charging I'm also passing through the generator AC to the rest of my system.

 

[50ShadesOfDirt]

Interesting ... I actually recycle my non-inverter gens (I keep two on hand at any time, such that if one is down, the other is available). If a gen dies a horrible death (and is out of warranty), I feed it's parts into the next ... works as long as I can keep getting similar models from gen manufacturer. You are a braver man than I am, to do something similar with those jet engine design/packaging/complexity of inverter-gens.

On THD, I've been running non-inverter open-frame gens for upwards of 10 years now ... never a problem with any of my electronics (we've got it all). I think surges are a bigger problem, and the more likely killer of electronics, than THD. Our magnum inverter passes thru power from a wgen9500df, so upwards of 25% THD ... no issues from inverter, or anything else in the household.

I can never get any true EE's to weigh in on the issues at the home level, so I've just decided (after tons of research) that THD isn't really a problem ... maybe one day we'll have THD "tilt" meters on the sides of electrical devices (as what are on big shipping packages).

 

[Symbioquine]

maybe one day we'll have THD "tilt" meters on the sides of electrical devices (as what are on big shipping packages).

Haha, that would be great!

I think surges are a bigger problem, and the more likely killer of electronics, than THD.

I'm no EE, but my (vague) impression is that THD directly causes surges if you have any sizeable motors in your system - the waveform shifts/distorts and then the back EMF can stack with the new waveform resulting in a voltage spikes.

 

[50ShadesOfDirt]

Never heard that about THD causing surges, and certainly not in the home sector, thus causing me to lose more hours investigating further ... however, the research is fun/educational (for me).

Perhaps that is a possibility in the "large motor" sector (industries with monster motors) ... but then, their power infrastructure is such that EE's are working for/with them to prevent such power issues.

I have about 90% SMPS devices (TV's, computers/laptops, 100's of wall-warts, etc.), and 10% motors (water pressure booster, fridge/freezer, washer/dryer, etc.) ... that means that 90% of the devices in my household are dumping THD back out on the house wiring. None have been damaged due to THD in my decade of operation with high(er) THD ... all live their normal life span (warranty period + 1 day, but sometimes longer).

But then, I do have SPD's in place ... that was an easy fix to potential surges of any kind.

 

[SacRV]

Interestingly enough I’m on my second XP9000iH.

The front panel on my first one died after about 6 months. I called DuroMax and was instructed to take it to a local repair shop. I assumed it burned out as the generator was running during a 100+ day. The repair shop was unable to repair the generator so DuroMax sent me another.

Then last week, after having the replacement for 6 months it did the same thing..dead front panel. However, this time I couldn’t contribute the problem to heat as it was 40 degrees outside. It was only running for about an hour in a half with a small load of about 2,500 watts.

I took it to the same repair shop and the owner told me about the fuses tripping in these. He said there are three behind the panel and has had to replace the fuses on several of these. I’m still waiting to hear if that’s the issue with this one. But considering this is the second time this has happened I’ve decided to cut my losses.

I ordered a Genmax GM9000ied yesterday with a 4 year extended warranty. Spec wise it’s the same generator, however it comes with a 50 amp plug and an internal engine fan that I think will be beneficial during the summer.

DuroMax has told me if it needs to be replaced they’ll just refund me, which is just as well since it cost a lot more a year ago then what they’re going for now. If it is the fuses and I get the same unit back I’m just going to sell it.

I will say I’ve been really happy working with DuroMax and they have been great every time I’ve called/emailed them. Unfortunately, Genmax is a Chinese company with no office in the US, which is concerning and the main reason why I bought it with the extended warranty.

 

[Symbioquine]

Interestingly enough I’m on my second XP9000iH.

The front panel on my first one died after about 6 months. I called DuroMax and was instructed to take it to a local repair shop. I assumed it burned out as the generator was running during a 100+ day. The repair shop was unable to repair the generator so DuroMax sent me another.

Then last week, after having the replacement for 6 months it did the same thing..dead front panel. However, this time I couldn’t contribute the problem to heat as it was 40 degrees outside. It was only running for about an hour in a half with a small load of about 2,500 watts.

I took it to the same repair shop and the owner told me about the fuses tripping in these. He said there are three behind the panel and has had to replace the fuses on several of these. I’m still waiting to hear if that’s the issue with this one. But considering this is the second time this has happened I’ve decided to cut my losses.

I ordered a Genmax GM9000ied yesterday with a 4 year extended warranty. Spec wise it’s the same generator, however it comes with a 50 amp plug and an internal engine fan that I think will be beneficial during the summer.

DuroMax has told me if it needs to be replaced they’ll just refund me, which is just as well since it cost a lot more a year ago then what they’re going for now. If it is the fuses and I get the same unit back I’m just going to sell it.

I will say I’ve been really happy working with DuroMax and they have been great every time I’ve called/emailed them. Unfortunately, Genmax is a Chinese company with no office in the US, which is concerning and the main reason why I bought it with the extended warranty.

Thanks for sharing your experiences with these generators @SacRV! Please do post back once you hear what the repair shop finds and how you like the Genmax GM9000ied...

I suspect you'll find the Genmax GM9000ied is a very similar generator (like most of the parts probably come from the same factories) so the main reason to switch would probably be a preference for working with one company or the other.

it comes with [...] an internal engine fan that I think will be beneficial during the summer.

Oh, that's an interesting difference though!

I'm curious once you get the Genmax if you'd be willing to take a picture of the propane fuel solenoid valve when you do the initial oil change? We already know that's one of the causes of blown front-panel fuses on the DuroMAX so knowing if the solenoid is the same exact model could be useful for predicting if the same failure mode is to be expected. (Admittedly, there could be other subtle differences even if the valve is the same one - like they could fuse the solenoid independently of the front-panel and even provide a little LED light to indicate that failure.)

 

[SacRV]

I'm curious once you get the Genmax if you'd be willing to take a picture of the propane fuel solenoid valve when you do the initial oil change? We already know that's one of the causes of blown front-panel fuses on the DuroMAX so knowing if the solenoid is the same exact model could be useful for predicting if the same failure mode is to be expected. (Admittedly, there could be other subtle differences even if the valve is the same one - like they could fuse the solenoid independently of the front-panel and even provide a little LED light to indicate that failure.)

I'm not sure what the fuel solenoid looks like or where it would be located. If you can help guide me I'll be happy to look.

In your original post you talk about the fuel solenoid not designed for continuous duty, which could be my problem if that's what went out in the DuroMax. Our generator is connected to a 300 gal. propane tank, which we run exclusively on. Typically we use the generator for a few hours in the morning and again at night. During the summer it'll be on during the day in order to run the A/C.

I've read the DuroMax manual front to back and nowhere does to warns users about extended use on propane. If that's the issue, then these manufacturers need to replace that part with a better designed one and inform customers.

I am SO GLAD I paid the $185 for the extended warranty, I'll sleep so much better knowing I'm going to be covered.

 

[Skypower]

Thanks so much for all the info!
I’ve got the 9500 predator (less display and dual fuel). It’s been rock solid. I’m going to dump the fuel into my car and put a fresh tank in since it’s been a while. I put a load on it and charge the home batteries for half hour every few months just to exercise it. The thing starts so fast I don’t know what it starter sounds like.

 

[Symbioquine]

I'm not sure what the fuel solenoid looks like or where it would be located. If you can help guide me I'll be happy to look.

On the DuroMAX XP9000iH, it is located just inside the housing on the left hand side of the little panel that comes off for doing oil changes. It probably has a brass base with a black hose going in/out of it near the bottom and a cylindrical part above that with two wires coming off it. The one from the DuroMAX XP9000iH looks like this;



Obviously, it could be different on the Genmax which is why I asked

 

[SacRV]

Thanks that should be easy to spot. I’ll follow up with what I find after I open it up.

 

[SacRV]

I shared the concerns about the fuel solenoid with my contact at DuroMax and this was his response..FWIW.

Thanks for sending that over. I’ve had my concerns on that solenoid for a while because I have seen some issues that stem from it. I know that piece was changed up (in design) but the issue is that a lot of old stock still has potential to run into the issue. The weird part is that it isn’t a high-quantity problem across the units in general, but it seems that it has something to do with the issues in the cases where problems do occur. The downside here is that I’ve tooled around with the same idea. I’m not sure who this person spoke with, but based on their wording, I can certainly tell you that it wasn’t me. Where I saw an issue with this “fix” is that the solenoid, for lack of better words, isn’t compatible with the PCB (computer). Solenoids generally operate one way… once power is received, the solenoid operates. This implies the signal needs to be momentary, and on-demand. The PCB in these inverters sends a constant signal… which now you can see why the solenoids, that do burn out, have their issues. The issue really boils down to a solenoid not holding up to the specs it was designed for. I have mentioned on several occasions to several shops that we can always try the parts (I can reimburse) and see what we get. After field testing on some other units, let’s just say my confidence in the solution is not high. The new units have been adjusted with a different setup/part just to account for the issue. It’s weird territory though. 9kWiH units, in general, do not have this problem as a common issue (which is why we are so willing to replace – generally the issue is an afterthought at that point), BUT I would also say that when they do have issues, then this problem is more common than other. Basically, it's not a mass-defect situation, but it is something we’re aware of and have changed. The issue is really that the old stock doesn’t see those changes…and this includes replacement units that dip into old stock.

 

[SacRV]

On the DuroMAX XP9000iH, it is located just inside the housing on the left hand side of the little panel that comes off for doing oil changes. It probably has a brass base with a black hose going in/out of it near the bottom and a cylindrical part above that with two wires coming off it. The one from the DuroMAX XP9000iH looks like this;

View attachment 144379

Obviously, it could be different on the Genmax which is why I asked

I opened up both side panels but couldn't find anything that looked similar to this part. The closest I could find were these.

 

[Symbioquine]

Interesting @SacRV, thanks for sharing those!

The part numbers from the first picture 24BYJ28/24BYJ48 seem to be stepper motors - so it's possible that Genmax switched to a motorized ball valve. Though I'm not sure why they would need two of them - maybe one is for the propane valve and the other is choke?

The second picture kind of looks like some kind of switch/manifold... Does its location inside correspond with the fuel selection switch on the front panel?

 

[SacRV]

Interesting @SacRV, thanks for sharing those!

The part numbers from the first picture 24BYJ28/24BYJ48 seem to be stepper motors - so it's possible that Genmax switched to a motorized ball valve. Though I'm not sure why they would need two of them - maybe one is for the propane valve and the other is choke?

The second picture kind of looks like some kind of switch/manifold... Does its location inside correspond with the fuel selection switch on the front panel?

The device on the second picture was connected to the airbox towards the front panel. Attached is a parts view of the generator, I think you'll find it helpful.

 

[Symbioquine]

The device on the second picture was connected to the airbox towards the front panel. Attached is a parts view of the generator, I think you'll find it helpful.

Yeah, that's a great reference.

I think I've seen that PDF before, but I don't think it answers my question. I believe that PDF is for the gasoline only version of the generator so it doesn't show/describe parts that are specific to the dual fuel models - like the internal propane regulator (which I know it has from one of the Gavin's Garage videos) and the fuel solenoid/motorized-valve (which I don't know if it has).

If it doesn't have a solenoid or motorized ball valve, then I suspect it is less wise to leave the Genmax GM9000ied connected to propane all the time - such as in a standby-style installation. The manual kind of suggests as much because it specifies turning off the propane as part of the shutdown procedure. Anyway, for many use-cases it won't matter, and I'm not considering getting the Genmax so it is mostly just a matter of curiousity at this point.

 

[SacRV]

I got a call from the repair shop about the XP9000iH with an update.

The owner said he got it running again. BUT every time he switches it to propane the fuse behind the panel blows. This was the same issue I had with the first one. He said he looked at the fuel solenoid but thinks its for gas and not propane. I didn't question him more about that since at this point it's a moot point. DuroMax has previously said they will refund me if it is unrepairable this time. He was sending everything over to them for processing. I'm hoping I get no resistance to refunding me what we paid, $2,826 in Nov. 2021.