Let me know if this answered your question. We just got done replacing our old water heater, and need to replace the vent pipe. For this reason, water heaters with a power vent should not be installed in small, enclosed spaces. I have a gas hot water heater, installed in 2004. 14 year water heaters are unpredictable. When I turn on the hot water for about 45 seconds, I saw a small explosion (size of draft hood) from the WH by the draft hood. Gas vent pipe from Grainger, manufactured by reliable companies like Ameri-Vent and Bosch, comes in lengths of up to 4'L. I have a nautual draft water heater can i change it to a induced draft by just adding a motor or is there something I ned to do ? Thanks for the quick reply!!! Hello, It looks like there’s enough of fresh air in that room and since you’ve clarified that second “explosion” it seams to be ignition delay issue. If you look inside the pipe and it appears to be clean / no rust, there is most like no draft problems and no worries about exhaust gases backing up into the house. The typical vent installation of the tankless indoor water heater is horizontally through the sidewall or vertically through the roof. In order to do this, two critical measurements must be taken: one on the ceiling above the water heater and one that is the distance from the attic floor to the roof. Get a licensed HVAC contractor, visit your local building department and find out who has approved such installation. It’s easier to run the vent if you install a “power-vented” type of natural gas (or propane) water heater. CORRECTIONS: The vent pipe is a 3″ Type-B double wall, and it’s 5′ straight up thru the roof with a cap. Your information will *never* be shared or sold to a 3rd party. We've got millions of parts, hundreds of brands, and thousands of step-by-step videos— everything you need to find it, fix it and finish the job right. Otherwise, I’d look for some other source of that odor, a floor drain, open sewer line, sump / ejector pump well, etc. Pieces of mortar, stones / brick often fall down the chimney, start accumulating, blocking the flue, restricting exhaust gases, resulting in condensation and elevated levels of CO. They also operate more quietly than their power-venting counterparts. First, consider the ambient temperature of the air around the vent pipe. The tank is 21″ in diameter with a 24″ diameter aluminum leak pan under it. Please give me your advice, thanks. x 5 in. Small holes start appearing on their surface – most common areas are along the bottom portion and on connectors. Gas water heater installation may seem intimidating, but it's actually easier than you may think. After I read through your web-side. Venting through existing chimney: [Illustration above] An unused chimney flue or masonry enclosure may be used as a passageway for the installation of the water heater vent pipe. Chimney liner is currently required by code so if you’re performing major repairs on your chimney or replacing any of the appliances – it must be installed and appliances connected directly to the liner (rain cap is required too). In both cases, the water heater needs to be located near an exterior wall or a chimney for the venting system to work properly. There are two other chimney ports for fireplaces, how can I direct the intake away from exhaust from the other ports (1 unused but functional wood fireplace in the middle and 1 seldom used natural gas fireplace on the other side)? Let me know if this helped and if you have any other questions. Also, I’m worried about possible gases in the house. Forcing a gravity-vented gas-fired water heater to vent "down" is defying gravity, impeding the draft, and risking dumping fatal carbon monoxide gas into the building. The pilot routinely goes out, if the A/C is running and the heater kicks on the exhaust does not go up the vent pipe and instead is pulled into the house. You didn’t mention how tall the room is and if it has any constantly open ventilation ports, but assuming 17’x4’x8’ ceiling you’d need 3 times as much of air to support complete (safe) combustion process of the water heater (based on 30000 BTU’s which should be stated on the label attached to the water heater / more BTU’s requires more air). I’ve even let the 36″ entry door wide open, and the “puff-back” still happened. Hi Mike, The general rule for venting two water heaters into a common connector is that its diameter must be equal or more than the larger diameter vent pipe + 50% of the smaller diameter vent pipe. The gas should ignite immediately after it’s released from the burner. It might be the gas valve which is malfunctioning resulting in an erratic opening and closing. Recently I noticed a problem which never happened before, and I’ve had this home for 7 years. Bend out small sections of the pipe and attach it directly to the vent hood with screws (Photo 6). It is caused by moisture condensation on the interior walls of the chimney and metal vent pipe. I performed the draft test using a flame at the base of the vent hood and there was a smooth steady draw toward the vent. Installing an induced draft motor on a natural draft type WH that has not been designed for it could disrupt proper combustion process, result in burner operation malfunctioning, and possible CO poisoning. Simply because it hides problems like corrosion or holes developing on surface. b keep this manual in the pocket on heater for future reference whenever maintenance adjustment or service is required. When you compare to the typical vent installation of the tank-type water heaters, tankless brings more flexibility and is cheaper, especially with the sidewall installation when remodeling the house. You can go over to the manufacturer’s website or simply give them a call and ask about your particular model. Along one of the 4′ sides, there is also another 8″ x 16″ vent. There is no chimney cap, but never noticed water until Feb 2011. The bi-product of incomplete combustion is carbon monoxide… Ask your HVAC guy about providing calculating sufficient combustion air supply for them. Join the Repair Clinic VIP email list for updates and special offers! The top of the chimney is at least 36″ above the peak of the roof line. If you run the fireplace and the water heater at the same time, your appliance might start recirculating exhaust fumes from the fireplace. However, this shouldn’t cause melting of that plastic, with a proper / strong draft, exhaust gases should be pulled through the vent pipe / chimney. Are there any HVAC system air return ports inside the utility closet or next to the combustion air supplying ports (if such exist)? Page 15: Water … Installation of water heater must be accomplished in Hi Karl, ideally the water heater vent pipe connector should be even with the interior surface of your chimney’s flue. the chimney above the roof is in very poor condition. –Must not be plugged or blocked. You didn’t mention the WH draft hood, vent pipe and chimney flue diameters, so I don’t know if this is the reason for the flame color issues. 2. The detector batteries should be checked regularly. Unfortunately you’d have to make a few holes in the chimney along its length in order to install those rods. Correct combustion, vent action, and vent pipe installation are very important in preventing death from possible carbon monoxide poisoning and fi res (see Figure 14 & Figure 15). © CheckThisHouse - 2021 - All Rights Reserved. residential gas water heaters installation and operating manual keep this manual in the pocket on heater for future reference whenever maintenance adjustment or service is required. However, to be on the safe side, you should properly calculate the entire run of your WH vent pipe. Check this – air return and combustion air. 1. new electric water heater / remove old chimney / you have to run 220V power line to the water heater’s location. If space restrictions require the water heater to be installed in a utility closet, make sure the closet doors are louvered, or space left at the top and bottom of the doors, to increase air flow. Do you think I still need more “vent?”, I will call manufacturer while waiting for your response : ). Flame discoloration is in most cases related (like you’ve mentioned) to inadequate amount of combustion air that must be supplied to sustain complete burning, without producing CO (yellow flame does that). Then … Such installation could create pyrophoric conditions and a fire-hazard. I am planning on replacing my old gas water heater with a 40 gal tank. Our water heater is in the basement and we didn’t know if there is any other way to vent it. Can I add a 45 to reconnect to the roof vent? I’m sure you’ve heard this a few times, but your website/information is very useful! For horizontal installations is should be supported every 3’ – 3 ½” to avoid sagging … I was absolutely clueless, I had ours all wrong. I am in the process of purchasing a new hgh efficiency furnace. The new water heater has a sealed combustion chamber with a screened combustion air intake around the bottom. On any horizontal sections of vent, make sure the pipe slopes down toward the water heater 1/4 in. Let me know “verdict”. Do I need to install a liner? I keep the “vent window” closed year-round and run a dehumidfier in the summer, but it’s a lost cause. vent systems are: (1) avoid an excessive number of turns and bends (Figure 5) and (2) maximize rise; minimize run. Vent Pipe Through Roof (30 cm) Min. Just to clarify my comments earlier regarding the “explosion at the end of the cycle.” That doesn’t happen. Gas water heater draft hoods act as a device, which in case of down-draft (a condition which forces air / wind back into the vent pipe / chimney), prevents air from extinguishing the gas burner. You can also explore Repair Clinic’s DIY content library to watch videos and read articles concerning common problems affecting water heaters, how to test certain components, and how to install new parts. There’s more about the water heater vent pipe in my article below the video. When using water softener sodium is added in the process and anode rods tend to corrode much quicker, sometimes in as little as six months if the water is over-softened. Gas service company rep said (on phone) “water leaks from vents” indicate chimney problem. Last year my old water heater went out, and I bought a brand new one from Home Depot. Natural gas or propane hot water heaters are generally less expensive to operate than electric heaters, but installing a standard vent in a house without an existing chimney is expensive.