CD100A Combustible Gas Leak Detector

I am an HVAC service tech. This combustible gas detector is a professional quality tool, it works exceedingly well and is unbelievably sensitive. It’s sold at a number of HVAC parts houses. It detects basically any combustible gas at levels at least as low as 50 ppm (parts per million). It is not auto-zeroing which I actually prefer. That means it doesn’t automatically desensitize itself with exposure to combustible gas. You can adjust the sensitivity yourself as needed meaning you can decrease sensitivity as the area is saturated with gas and you zero in on the leak and at ANY point you can crank the sensitivity back up without having to wait a long time or restart the detector & move back outside. It also means when you initially start it up you have to adjust it to the required baseline. Give it a minute or two to warm up & adjust it to a few clicks per second. I’ve used this detector at least 8 or 10 times so far. It pick up instantly with no delay & recovers very quickly. On both accounts it is MUCH better than my previous detector. It is also INSANELY sensitive and I mean CRAZY sensitive. A funny experiment, it’s so sensitive that it will detect methane when you put it close to anyone’s rear end and that’s when they are not passing gas. The point being, don’t let the extreme sensitivity of this detector drive you crazy. It WILL pick up on the most insanely small “leaks”. I would suggest confirming all leaks found by this detector with a bubble solution. Not because of the reliability of the detector but because the leak could be so small as to be insignificant. Gas lines typically hold no more than 2-3 PSI of gas (on your side of the gas meter). They are tested & passed at 10 PSI. By their nature, gas lines are not exceptionally tight. Most gas lines, if pumped up to 10 PSI & left for a week, will have lost a good amount of pressure. My point being, if you find a leak with the gas detector but it won’t show up with a bubble solution PROPERLY ADMINISTERED it’s too small to worry about. You could search the entire gas line on a small old house & probably find over a dozen “leaks” that small and it could still pass the pressure test. Here’s another pointer, sometimes it’s normal to smell a little gas. What? That can’t be right? Your gas meter has a pressure relief on it. It will, from time to time, purge a little gas, especially when gas appliances are turning on & off. Just because you smell gas when you walk by the meter doesn’t mean there’s a problem. When your gas furnace shuts off the gas valve closes and the gas inside the distributor equalizes to the ambient pressure, but it’s inside an enclosed tube so not every last bit gets blown out of the flue by the inducer motor. Everything shuts down and over minutes that tiny amount of gas slowly dissipates. If you pull the door off the burner compartment of your furnace at the right time you’ll smell gas. This detector will pick up on it. It’ll hit big right at the orifices where the gas comes out. That doesn’t mean there’s anything wrong. What I’m getting at is, be safe with gas but understand just how sensitive this detector is and if you’re not sure what is or isn’t normal call a professional. The professional would be more than happy to have this detector in his arsenal of tools.

I originally bought this to help troubleshoot a propane stove in my Airstream, which I suspected was leaking. There was just a touch of a long-lingering gas-like odor, but many of the gas connections were too hard to reach to try testing with water and soap. After reading the reviews, and cringing at the price, I finally ordered one. I was excited when it arrived. My foray into serious, committed gas detecting had begun! The unit has a bit of heft, and feels well made. And, it's super easy to use. After inserting a battery you simply spin the dial to turn it on and then increase the sensitivity, until it starts "clicking" repetitively in clean air. Extend the flexible probe, and start poking at things you think might be leaking leaking combustible gas (i.e. propane). If it finds even a little bit of stray gas, it starts clicking faster. If it finds a major gas leak, it clicks so fast that it sounds like it's buzzing. Think Geiger counter. So, I started probing around near my gas stove, where I thought the leak might be. Nothing. Because of the long probe, it's easy to press it up against each individual fitting to see if it's tight, or leaking. I pressed it against each fitting going to the stove. Still nothing. Could my dual electric/propane refrigerator be leaking? I checked each connection on that, too. Still nothing. Maybe the detector wasn't working? I turned on my gas oven, without the pilot being lit, and held the probe near the gas outlet. The detector immediately went crazy. So, it was working. To make a long story short, there was no leak. It turns out that my old carpet was just really smelly. No, not kidding. But I wouldn't have known without the detector. So, it turns out that a sensitive detector is useful not just for finding gas leaks, but also for determining that there really is no leak. But, my detector hasn't been sitting idle. In the meantime, I've used it to check every visible gas connection in my house for leaks. It's helped me pinpoint a propane leak in my camper shell. I just used it to check every new propane joint after having to replace my dual propane tank automatic changeover regulator after it failed, and it almost instantly found a couple of leaks which allowed me to quickly fix the bad connections. And, it even helped me troubleshoot a loose gas connection in a house I sold recently, after the home inspector flagged a gas leak. Without this unit, I would have had to call a contractor to trace it. Instead, I was able to quickly find the leak and fix it myself, which turned out to be nothing other than a loose connection without the sealant which it should have had. That alone more than paid for this unit. If you hold this up to someone's mouth, you can even tell if they've been drinking. Don't ask me how I know. Not trying to sound like I'm an expert here. I'm really just a regular DIY kind of guy that likes to work on relatively easy stuff. But, if you have an RV, or a house with natural gas, or do any kind of work whatsoever with propane, or natural gas, or RV systems, this awesome tool can give you a "sixth sense" to find that (possible) gas leak. It helps you quickly determine (1) is there a leak? (2) if there is, exactly where it is, and (3) based on #2, the added ability to help determine if it's something you can fix yourself easily, or if it's maybe time to call in the real experts.

This really works. I smelled gas from a connection to my furnace. The plumber resealed and tightened the connections. No smell, no bubble leaks. But still got a leak reading. Other joints did not get a reading, so the plumber replaced the small pipes, new sealant dope and now no leaks. The downside is this is so sensitive, it detects leaks which a plumber may not normally try to fix. Maybe it was the old sealant or something that was smelling. Anyway it works great, but be award, you may drive your plumber up the wall with this thing. I did ask the community how much background noise is acceptable inside the house. We get a faster ticking throughout the inside of the house. EDIT, Update. After a couple of weeks, the background noise went away in side the house. That tells me that our house was full of the bad air, and am so thankful I have this to check the air now.

When I received the detector, I tried to turn the switch on, and it only spun, did not click on or off. Also, there were no instructions that come with the device, just a bubble pack cardboard advertising a few features. Since I need this, and it has been rated higher, I sent this one back to Amazon for a refund, and ordered a new one. I am hoping that I just received the bad 1 in 1,000 on the first go-around, and the next one works as advertised. [Update - 1 week later] I did receive the new detector, and it was in proper working order. The unit had a battery already installed, and also included instructions. This makes me conclude that the first unit I received was someone else's return, and they simply put it back on the shelf. Now, as far as the operation and my observations using this unit, it appears to be pretty good. I was able to identify the location of a propane leak in my RV, which I verified using the soapy water test to see where the bubbles formed. I was able to disassemble the connection, add the proper gas (yellow Teflon) tape, and determine the leak was no longer present. Using the wand detector, I quickly verified the integrity of the rest of the connections. I did notice, it is so sensitive, that when I hold the sniffer tip in my hand, my personal gases make the detector tick faster. Also, just breathing on the tip does the same thing. Hold it near some plastics also has the same affect. Overall, I am changing the rating from 1 to 4 stars. This is for the equipment. Amazon disappointed me by sending me a used item, but they were very fast with crediting my account for the return, which UPS picked up from my house the next day, at no cost to me.

When I needed to find a gas leak in a cluttered basement, I rapidly concluded that the traditional approach of coating the pipe joints with a soap and water solution and looking for bubbles would take a very long time and create a mess. With costs for a plumber running to $100 per hour, a gas detector quickly began to look like a good investment. The UEi CD100A seemed just the ticket -- simple, inexpensive, and reasonably rugged. It turned out to be all of those things. Operation is simple -- just turn the detector on (in clean air), wait for a minute or two, adjust the audible tick to a slow but steady rate, then move around until the tick rate increases. The faster the tick rate, the higher the gas concentration. (Imagine a Geiger counter that detects gas instead of radiation...) Just move the sensor along the piping until you find where the tick rate is highest, and you've found the leak. The price is very reasonable for an electronic instrument of this quality. Most detectors of similar quality are more expensive. The device is also reasonably durable. The gooseneck is a bit delicate (especially where it joins the body of the instrument), but this is a complex electronic device, not a hammer. If you treat it with a bit of care it should last a long time, though the sensor module will likely need to be replaced every few years. (This is just the nature of electronic gas sensors, and isn't a weakness of this particular device.) It's worth noting that this is a leak detector, not a gas level monitor. It is designed for plumbers, appliance technicians and DIYers who need to locate a gas leak and/or to verify that there are no leaks after working on gas plumbing or appliances. It's not intended as a continuous duty gas safety monitor. There's no readout of gas level in PPM, so there's no way to determine the actual level of gas present. If you need to locate a leaking fitting in a gas line, this is the perfect device. If you're looking for a gas monitor for your basement, or for OSHA compliance, this device isn't what you need. As long as you're not expecting the device to do things that it's not designed to do, it's a great instrument. Pros: simple to use; inexpensive; reasonably durable; compact Cons: gooseneck not quite as durable as it could be

This device has 2 primary uses: finding a leak, and insuring that there is no leaking gas! It will give you the confidence in both functions. I just replaced a tank with a tankless water heater and had to re-plumb the propane line. Afterwards there was a faint oder of gas, but extensive soap testing gave no hint of which of 20 joints might be leaking, so I purchased this. Within seconds of using it, a minute leak was located down to which side if the joint had the leak. After removing the valve from the fitting, adding more tape and reassembling, the tester assured me that there was no more leaking gas anywhere along the system. Gas leaks can be dangerous and, unlike electrical systems, there are no safety circuit breakers or GFCIs to trip. This is a very sensitive instrument, easy to use, nothing complicated to understand or intrepid. Just turn it on with a rotating click rate thumb wheel, wait 10 seconds for the sensor to stabilize, adjust the thumb wheel for about 2 clicks per second, and move the long probe around the pipe joints listening for a noticeable increase in the clicking rate - more gas, faster click rate. The red LED in the tip gives some light into the space you are probing, I'm just not understanding why the LED isn't white, but it works fine.

I was extending the gas pipe under the house to allow installation of a gas stove. I figured I'd need a leak tester, but couldn't find one to rent at what I considered a reasonable price. as a tool lover, that gave me the perfect excuse to buy one! This one is simple to use, and I had no troubles with it at any time. The flexible tip can reach into areas difficult to get at with hands, and the red tip light helps immensely without affecting low-light vision. It's simple to use, and I bought a little hard case at a thrift store and fitted to hold it safely. This unit worked very well: my work was tight, but then I did an end-to-end leak test from the meter to all endpoints, and discovered two leaks that have likely been there for years. While my house is rather old (110 years) and the crawl space is well ventilated, I'm glad to have fixed those leaks, just in case. A 100+ year old house built of ceder would burn very easily...

This device appears to actually detect oxygen levels. When a gas displaces oxygen, sure the device will work as described. However, a lot of things displace oxygen. You can test this theory easily by simply breathing near the sensor. Just a tiny amount of your breath will make it go crazy. Carbon Dioxide isn't a combustible gas yet it will trigger the device. Water will set off the device and this is what makes it useless to my particular issue. It took me awhile to figure out that it was water/condensation/humidity that was making the thing go crazy. It wasn't until after I took a shower that I found this out. Even moving the sensor close to bottled water sets it off (uncapped, sensor over the top of the bottle). Bring the sensor near any kind of moisture and you'll get a false positive. You can't even get the device near yourself without causing a false positive. I would stand on this stepstool and the device would pick up a leak but when I stepped down and farther away from the sensor, it would no longer go off. I then figured out it was going off as I neared the sensor, even from a couple feet away. That was when I showered to make sure there was no chemical or something on me, but then it went crazy in my house until the moisture from the shower left the air. Then I started finding all kinds of non combustible gases that would trigger it. Very disappointed as it is useless for me as there are too many things causing false positives here. I have no idea when it is actually gas that is setting it off or if it is any of the many false positives.