So in the winter we get short hot showers. It didn't seem to matter as this Sunday night it was -25 and the new hot water heater froze. Here are some solutions. We can think of a furnace as lungs. The power of the draw increases as the vent duct heats up. Sprayed down the outdoor unit with Frost King coil cleaner foam (I was able to turn the electricity off outside but did not take the unit apart, just went at the sides as much as possible). I have a Reem hot water heater. This happens when the exhaust gases from an atmospherically vented water heater spill out into the room, rather than safely leaving the house through the vent. Air return vents are necessary for the 'inhale' process. The simplest way to check for backdrafting is to put hands around the draft hood, mirror or glass. Upvote # 7 Inspect the vent pipe for leaks, and tape all penetrations or replace the vent pipe or hose. Like most commonly used mechanisms in your home, after time they can become loose or damaged. Additionally, double-check that your thermostat is set to "HEAT.". If cold air is seeping into your ductwork, it must blow out of the duct registers before the furnace's warm air canthus it feels like air-conditioned air is ventilated . Water heater is LP gas, located a few inches away from the basement wall with a vertical rise of 18 inches going straight up to the elbow with a proper pitch. How to check is the water heater backdrafting. There is cold air coming in from the vent falling on top of the heater and cooling the whole room. However, if you feel slow, drifting warm air, that means it is releasing into the same room. According to Larry D. Armanda, Owner of Therma-View Infrared and Energy Consultants, orphan water heater-related backdrafting occurs "when the draft temperature is so low in the water heater that it often can't overcome the slug of cold air inside the chimney, and the flue gasses can't escape so they come back into the CAZ (combustion . Ducts should be tightly sealed and insulated to keep the air in them warm during the winter. RSES Certificate Member RSES-SWRA Past President Simply put, a cold air vent returns cold air back into the furnace. Here are just a few things that could mean: 1) Dead Batteries in Thermostat Seems silly, but you'd be surprised how often this has happened. Size wise, you should have a vent not less than 3 inches, but you need 1 square inch for every 1000 btu on the heater. There are two main functions for most fresh-air intakes in homes. If it is set to ON, that may be your problem- switch it immediately. Next verify the thermostat's fan setting is set to AUTO, not ON. Replaced filter in what I think of as the furnace. If you feel cold air running towards the vent, that means that your ventilation system is working correctly. Step 3. I double checked the saddle valve on the supply water line to the humidifier and it is also 'off'. One night when it was -20 degrees outside the water heater froze and started leaking. A Fix to Cold Air Coming Out of Vents: Duct Insulation & Sealing Services. The total run is only about 5 ft plus a few 45's which would make it about 17ft. Just turn the fan setting from ON to AUTO. This will stop any back draft on the heater when other exhaust fansd are ran. There are several reasons for this problem. Often, these appliances can be cut off from sufficient . Once you do that, your fan should only blow out air that is heated by your furnace. The heater's blowing cold, or the AC is blowing hot. There is cold air coming in from the vent falling on top of the heater and cooling the whole room. Hot exhaust from the water heater naturally rises up through the vent and into the air outdoors, creating a draw that promotes this upward airflow. Quality butterfly dampers are available that have a little spring inside, two flappers and a weather-stripped rubber stopper. The gap allows additional air to flow in and the combined air, if the ductwork is designed and installed properly, flows through the ductwork and out of the house. If it is set to ON, your fan will constantly blow out air, even when your furnace isn't heating it. Generally, the temperature at the supply vent when cooling with an air conditioner should be 16F to 22F lower than the air temperature entering the air conditioning unit from your rooms. You're standing there pushing buttons trying to heat up the house, but it's just not working. This happens when the exhaust gases from an atmospherically vented water heater spill out into the room, rather than safely leaving the house through the vent. If you have a house with 7 rooms, you need 7 cold air return vents. Hi. If cold air is seeping into your ductwork, it must blow out of the duct registers before the furnace's warm air canthus it feels like air-conditioned air is ventilated through your home despite the thermostat being set to heat at 72-degrees. Likewise for the air conditioner. A properly working damper will close and open easily . While the piping could be modified to use inside air and only exhaust outside, it would defeat the design. The OP said he has heat at passenger side wich means heater core is functioning properly, he also stated he checked one actuator, not all of them, just because he has air coming out the vent means nothing, seems as though some are not fully reading the original post he has heat on passenger but not drivers side yet has cold air blowing from . Before taping the exhaust hood to the vent pipe, check the gravity operated back draft damper to see if it is working properly. The vent consists of a vertical or upward-sloping vent duct that typically ties into a common vent. One of them is the poor vent installation, such as horizontal or downward slope - the vent pipe has been installed with the improper pitch; too many turns (bends - especially with the sharp and right angles), sudden diameter reduction, sags, dips, long vents The ON setting makes the furnace fan blow continuously, even when the heating cycle is not activated. In many cases, this leaves a very fine white powder in the vents that are then carried into your home. Check to see if your thermostat is set to ON or AUTO. It 'breaths out' hot and it 'inhales' cold air. Thankfully, this is an easy fix. There is a small plastic device called a damper flap that regulates the flow of air - in this case, it is supposed to keep cold drafts out and your heated air in. Backdrafting at a water heater is a common defect identified during home inspections, and it's almost always a condition that the homeowner or occupant is not aware of. 2) Clogged Air Filter. That's quite easy to understand. If you find that this is the case, you will either need to reseal or replace the damper. (when not running of course) The vent goes straight up from the water heater about 2 then a 90Deg. How can I fix this venting problem? The current vent leaves the heater going straight up a few inches, makes a right angle then another and heads straight up out the roof. What is a cold air return vent? You can also use the lighter or matchstick beside the . Hot exhaust from the water heater naturally rises up . I am having an issue with my water heater and would like some advice. He said that when your furnace is running (that you can hear it) it is heating up the air that is within the furnace. But once the flue has been actively chilled below some point it creates an "anti" stack effect when there is no burner adding heat to the stack, and cold air will continue to come down the flue until the flue warms up again (from either the burner firing for some period, or more slowly from the heat of the house.) You can hear it blowing, but no heat is coming out. I have a Reem hot water heater. The minerals in the water are also added. As the water in the humidifier is agitated, water particles enter the air. Otherwise it has to work a lot harder just to pull the air, which means you'll get less warm air coming out than you should. If you have a house with 12 rooms, you need 12 return vents. It is cooler in the basement but still not "air conditioner" feel. 2 Atmospheric vent systems work well (and without electricity) if they are properly designed and the home does not have backdraft issues. Can not see anything else unfortunately. Hope this helps. So in the winter we get short hot showers. One night when it was -20 degrees outside the water heater froze and started leaking. If the drain terminates under a bathroom sink, like most attic installed systems in my area do, capping the vent in the drain line can cause gurgling and knocking noises from the sink, and often a noticeable amount of air blowing up out of the sink drain, often with associated sink drain smells. I got another unit to replace this one and placed a 90 degree elbow and a "T" fitting on the end to block and wind from entering the exhaust. A draft hood is placed above the upper most part of the gas furnace to draw air into the chimney and makes it possible to draw more or less air through the chimney as necessary to create a constant flow. The difference is that a power vent water heater pulls in combustion air from the space around the appliance, then uses a fan to propel the exhaust through the vent. Vent goes essentially up and out the side of the house and meets all the venting criteria set aside including slope, length, limiting use of 90's etc per the Kenmore manual. It has 3" pipe. No furnace can adequately operate without sufficient return air supply. The difference is that a power vent water heater pulls in combustion air from the space around the appliance, then uses a fan to propel the exhaust through the vent. I got another unit to replace this one and placed a 90 degree elbow and a "T" fitting on the end to block and wind from entering the exhaust. First, verify the set temperature is higher than the room's temperature. A direct vent system pulls in . You can tell if it's time to replace batteries by referring to your thermostat's low battery notification. The minerals can precipitate from the heated air as it cools in the ductwork. The current vent leaves the heater going straight up a few inches, makes a right angle then another and heads straight up out the roof. Here's what that means- if your delta T is 16F, your furnace will add air that is 16F hotter than the return air. The idea with this type of system is that it doesn't use inside air for combustion. So, if the hot air returning to the air conditioning unit is 85F, the air coming out of the supply vent should be 63F to 69F. So when the water heater fires up it vents into the basement until the draft reestablishes. The system works solely through natural convectionbased on the principle that hot air rises. Ducts should be tightly sealed and insulated to keep the air in them warm during the winter. Mar 6, 2014. Basement is partially finished, can see the duct going straight from the blower to the vent in the basement and see a path of ducts going the other direction before disappearing under ceiling, but that seems to be the air return. turn about 2 to another 90 deg turn about 2 out the wall . First and most importantly, make sure your thermostat is set to Heating Mode. The first is to bring in sufficient combustion air for natural gas-burning appliances such as furnaces and water heaters. All piping going out of the house meets code, doubled wall pipe, exhaust pipe above roof. So, if your home's temperature is 50F, the air temperature in your supply vent will be 66F. Full Basement not finished so plenty of air. Solutions that don't use electricity would be best for off-grid use. The actual amount of combustion air - i.e., air flowing past the burner to provide oxygen and leave with less oxygen but more CO2 and possibly other combustion byproducts - is very little. If you have a battery-powered thermostat, ensure it has fresh batteries. If there is a blockage on the air vent outside, you will also run into this issue. The vent stack develops a backdraft in the following conditions: very cold outside air temperature, windows and doors all closed, exhaust fan running inside the house (bathroom vent or drier). This one comes from a company called Aeroflo at www.ContinentalFan.com. A power-vent model comprises an exhaust fan and only one pipe, which is exhaust, while a direct-vent model has two, one for air . Tape all joints including the connections to the fan itself. Yes there is an older Aprilaire humidifier hooked up to the cold air return but it has been turned off and not in operation. I even disconnected that water line from the humidifier to make absolutely sure that no water was going through it. How can I fix this venting problem? Backdrafting at a water heater is a common defect identified during home inspections, and it's almost always a condition that the homeowner or occupant is not aware of. As mentioned before, there are two types of venting systems used on tankless water heaters: power-vent and direct-vent. turn about 2 to another 90 deg turn about 2 out the wall and there is a 90Deg on the outside that points down and there is a bug screen (supplied with the heater) glued into that final 90. Turned off everything (master power) for 30 minutes and reset. For a heat pump or heater to produce warm air, air must flow easily through the filter. It didn't seem to matter as this Sunday night it was -25 and the new hot water heater froze. You will feel the warm gases coming out while the moist inside the flue gases will make the mirror/glass fog up if used as the checking tool. To properly heat your home, furnaces control their heating by maintaining a "delta T" of 16 to 22F. These systems work well but have one downside. The draft will change in the chimney as exhaust vents towards it - especially when going from cold air to hot. Instead, cold air from the top pushes the warm air down and traps it in the flue, creating water dripping down the furnace flue vent. A direct vent system pulls in. However, there is a significant amount of cold outside air coming in the 2 (system 636) exhaust from the power vent, and its enough to spin the fan on the power vent backwards. Butterfly dampers Any exhaust vent that rises up and out will have a tendency to let cold air fall back down that duct. The vent goes straight up from the water heater about 2 then a 90Deg. This is a more critical item if the units are enclosed in a small area with limited air available. The air blowing out of vent is that air, so when it starts to get cool it just means that that inside unit is cooling down and you just need to adjust something on the furnace that controls how long it runs after temperature . Power-vent water heaters use indoor air for gas combustion, while direct-vent utilize outside air. Standard water heatersthe most common typeoften use a method known as atmospheric venting. You should have 2 seperate outlets for air, 1 within 12 inches of the ceiling and 1 within 1 foot fo the floor. We can simplify that whole thing, however, with this simple rule of thumb: "Install 1 cold air return vent in every room that is larger than 100 sq ft (1010)". Have you ever felt air that's 66F? As the vapor sits in the flue it cools, creating condensation..