TONY3696

Ice forming on an evaporator coil causes leaks/flooding almost 100% of the time when it thaws. When the ice melts, it drips and runs places it was never intended. Emergency pans collect water that leaks through the furnace, but does nothing to protect the control board, blower motor, etc. This is why I say you need to make sure you have adequate flood protection. If you don't have an emergency pan, or it's not installed correctly, you will destroy your ceiling or flood your basement. Do a quick search for "AC ceiling leak" and browse through the pictures if you don't believe me.Reducing airflow across the heat exchanger will absolutely increase the temperature of the heat exchanger. If a system is properly sized and has adequate ductwork, closing a vent or two isn't a big dea…

Ice forming on an evaporator coil causes leaks/flooding almost 100% of the time when it thaws. When the ice melts, it drips and runs places it was never intended. Emergency pans collect water that leaks through the furnace, but does nothing to protect the control board, blower motor, etc. This is why I say you need to make sure you have adequate flood protection. If you don't have an emergency pan, or it's not installed correctly, you will destroy your ceiling or flood your basement. Do a quick search for "AC ceiling leak" and browse through the pictures if you don't believe me.Reducing airflow across the heat exchanger will absolutely increase the temperature of the heat exchanger. If a system is properly sized and has adequate ductwork, closing a vent or two isn't a big deal, the problem is that most are not. An easy way to check the heating side is to take the temperature rise of your furnace. All gas and oil burning furnaces have the temperature rise listed on the data plate of the unit. Measure the supply temperature of the furnace and subtract the return temperature, the result is your temperature rise. It should be right in the middle give or take a few degrees. If it's not, something isn't right and blocking vents, even just one, could make it worse. I know it seems like I'm exaggerating, but I go to dozens of houses every year with thousands of dollars in damage from airflow issues.I do this every day for a living and hold NATE Certifications in gas heating, oil heating, air conditioning, heat pumps, gas & oil hydronics, and air distribution. I also have a gas fitters license, oil burner license, EPA, and several manufacturer specific certifications; so it's safe to say that I know what I'm talking about.I'm not trying to take anything away from your work, it's very well done, I'm simply trying to save someone from a self-induced nightmare.

Nice Instructable, very thorough!I'm a residential HVAC tech and want to add a few words of warning. He touched on a few issues lowered airflow can cause, but there are a few more that need to be brought up. -Flooding-A frozen AC coil most likely will cause flooding in the immediate area around the indoor unit. In an unfinished basement it's not the end of the world, but can cause thousands of dollars if the basement is finished or it's in an attic. -Cracked Heat Exchanger-Lower airflow causes the heat exchanger to heat up more while the furnace is running. This puts extra stress on the heat exchanger and can cause premature failure. If it cracks, carbon monoxide and flue gasses have a path into the living space.-Noise-Increased pressure in the ductwork causes extra stress on the mo…

Nice Instructable, very thorough!I'm a residential HVAC tech and want to add a few words of warning. He touched on a few issues lowered airflow can cause, but there are a few more that need to be brought up. -Flooding-A frozen AC coil most likely will cause flooding in the immediate area around the indoor unit. In an unfinished basement it's not the end of the world, but can cause thousands of dollars if the basement is finished or it's in an attic. -Cracked Heat Exchanger-Lower airflow causes the heat exchanger to heat up more while the furnace is running. This puts extra stress on the heat exchanger and can cause premature failure. If it cracks, carbon monoxide and flue gasses have a path into the living space.-Noise-Increased pressure in the ductwork causes extra stress on the motor making it louder. Also, increased velocity at the vents increases noise.-Frozen Pipes-Cutting off the heat supply to select areas of the house causes uneven heating and may lead to pipes freezing. (Do you know where the pipes are in your walls?)Commercially available zoning systems are installed by professionals and a lot of work goes into making sure your system can handle being zoned. That being said, shutting down one or two vents usually isn't detrimental to the system, but it can be. Your best bet is to have a licensed HVAC tech evaluate your system to make sure it's able to handle the changes and that you have proper flood protection. Good luck, now go build something cool!!