HHO Product Reviews

Systems, Plans, Components and Parts

See Reviews From Other Users or Submit Your Own!

HHO product reviews on this site are provided two ways: From readers who have purchased and used the product, and also by HHONAR if we have tested or reviewed the product ourselves. Where we have done testing or reviews on an item it will be noted as "HHONAR Reviewed" and will include our review or test results and comments. If you are a manufacturer or vendor of an HHO product and would like to submit it to us for testing or review, please use our vendor contact form at the bottom of this page.

If you are a reader and have purchased and used an HHO product, we would like to hear from you. Please submit a review by using the review and comment form.

For reader submitted HHO product reviews we will note whether purchase of the product was verified or not along with the review by either "Purchase Verified" or "Purchase Not Verified". We caution our readers that reviews with unverified purchase should not be given as much weight as those where we can verify the reviewer actually bought the product--either by a receipt or other proof of purchase submitted by the reviewer or verification with the seller. If you are a reader and have purchased and used an HHO product, we would like to hear from you. Please submit a review by using the review and comment form.

NOTE: For reader submitted HHO product reviews we will note whether purchase of the product was verified or not along with the review by either "Purchase Verified" or "Purchase Not Verified". We caution our readers that reviews with unverified purchase should not be given as much weight as those where we can verify the reviewer actually bought the product--either by a receipt or other proof of purchase submitted by the reviewer or verification with the seller.

HHO Systems

Please note that in the hydrogen-on-demand marketplace there are many different HHO products being built and sold as "complete systems". However these can vary a lot both in quality and what they include: Some are as simple as an electrolyzer and a few attaching parts, while others may include the full gamut--an electrolyzer, auxiliary tank, bubbler/flashback arrestor, enhancers (like a MAP/MAF sensor, EFIE, etc), covalyzers/additives, fuel preheater, hoses, harnesses, and more.

*Not a "complete system", i.e. it does not include any electronic enhancers which may be needed in many vehicles to achieve the best gas mileage boost possible out of your system. If electronic enhancers are desired then add $200-$400 cost to systems with an asterisk. PLEASE NOTE that just because we say it is not a "complete system" because it does not incude an electronic enhancer with the kit DOES NOT NECESSARILY mean it will not work well with your vehicle. Just understand that you may require the addition of enhancers in order to realize the best gas mileage boost--or any at all--depending on your vehicle and how it responds to the addition of HHO to the combustion mixture.
**Cost shown is based on prices posted on vendor websites. Prices will vary with different vendors, options, shipping costs, etc. Costs shown here do NOT include professional installation (if professional installation is desired see how to find an HHO installer on this page).

On our comparison chart of top systems, HHONAR considers a "complete system" as one which includes AT LEAST an electrolyzer AND an enhancer, plus the attaching parts and instructions. This is because in most cases an electrolyzer by itself will not be able to provide significant mileage gains on late model (fuel injected) cars due to the way the car's computer is programmed to inject fuel. (For a more complete discussion of this, go here.)

HHO Plans

Like ready-made systems, HHO plans come in varying degrees of completeness and quality as well. HHONAR will include the best plans we have seen here, as well as reader submitted reviews.

Please be aware however that we do not recommend building your own HHO systems unless you are mechanically inclined and have the time, tools and workspace to do so, or simply do not have the money to spend on a ready-made system. For those who do want to go the DIY route, see our 'HHO How-To' page. And don't skip the safety tips found here --this is very important. Then check out the plans review pages:
Run A Car On Water
Water4Gas

HHO Components and Parts

HHO components and parts sources are included here for those who want to experiment with DIY, or simply want to add enhancers or optional add-on products to the systems they already purchased that may not have included these.

Other items here are useful for those who want to monitor or test their HHO system performance, for example by using a [scan gauge]. Or maybe you want a higher quality peripheral than is normally supplied in a system. Most fuel preheaters for example, are simply several brass fittings cobbled together and zip-tied to a radiator hose. We include a couple of high quality (albeit more expensive) professionally engineered alternatives.

Scan Gauge
VMU

Other HHO Products

Did you know HHO is being used for things like welding, cutting and heating? More new products are being developed all the time. We feature some of them here:

Other HHO Uses and Products