So I actually sealed around the pipes and all the little holes I could find, install my mobile to record the flame when I close the cover when furnace is running and there is not any change in the size or color of the flame when I close and open the cover so the 2" pipe should be sufficient air supply for the furnace. I also notice the furnace running significantly shorter when it turns on and that would be due to not pulling cold air from the outside through the house walls and windows but getting air supply through the pipe and I also notice there is not breeze coming in like it did before when I crock open the window when the furnace is running.
Hello. It’s a very good idea, but, I think you need more air inlet, that pipe seems too small. I suppose it should be the same area or bigger than the holes you closed. Cheers.
you might be right, on high efficient furnaces its same size as the chimney pipe, but there is no change in flame sound when I close the cover plus the inducer is pulling a lot of air and the furnace is not hermetically sealed either. I'll still look into it and test it make sure it gets the air supply it needs. Good point. Thanks
While adding some makeup air certainly doesn't hurt you have a lot of this all wrong ..... That itty bitty little inducer motor isn't never going to create enough negative pressure in your enitre house to cause it to draw air from the outside ...... All it actually does is create just enough negative pressure at the outlet of the heat exchanger to get it to flow into the main flue ..... In fact the way they get the efficiency in an 80+ furnace like that is to restrict it so most of the heat stays in the heat exchanger rather than flowing up the chimney ..... It doesn't actually blow air out, it just creates a negative pressure at the top of the heat exchanger .... It's rated at less than 50 CFM or about twice what an 80 mm fan on your computer pushes and the reason it runs at such a high RPM is because it has to overcome a lot of static pressure Makeup air for a furnace that size needs to be a 5" or 6" pipe (It's based on BTUs of the gas used ) and by taping off the vents on the door you risk the chance of sooting up your heat exchanger because of a messed up air to fuel ratio because it's not getting enough air ..... The 90+ furnaces have a completely different design and a much bigger blower (500 CFM high static pressure blower fans) tuned to work with a 2" PVC pipe .... It also has different burners and keeps the warm air in the heat exchanger long enough that it's barely luke warm air at the outlet allowing you to use PVC pipe for the exhaust .... It's a completely different and more complex design than an 80+ heat exchanger
Dude you going into lot of specs here, all I know is.... I sleep by open window and when it gets cold in winter it's just a inch or two open and when the furnace used to kick in I could feel the breeze coming from out side right the way until the furnace shots off, now I don't feel anything any more when the furnace turns on, so explain please. Thanks
awesome. very simple and cool.
Thank you! 😊
@@VladFredK it's a neat upgrade to make your furnace better. Thank you for sharing this.
So I actually sealed around the pipes and all the little holes I could find, install my mobile to record the flame when I close the cover when furnace is running and there is not any change in the size or color of the flame when I close and open the cover so the 2" pipe should be sufficient air supply for the furnace. I also notice the furnace running significantly shorter when it turns on and that would be due to not pulling cold air from the outside through the house walls and windows but getting air supply through the pipe and I also notice there is not breeze coming in like it did before when I crock open the window when the furnace is running.
Hello.
It’s a very good idea, but, I think you need more air inlet, that pipe seems too small.
I suppose it should be the same area or bigger than the holes you closed.
Cheers.
you might be right, on high efficient furnaces its same size as the chimney pipe, but there is no change in flame sound when I close the cover plus the inducer is pulling a lot of air and the furnace is not hermetically sealed either. I'll still look into it and test it make sure it gets the air supply it needs. Good point. Thanks
@@VladFredK Cheers.
While adding some makeup air certainly doesn't hurt you have a lot of this all wrong ..... That itty bitty little inducer motor isn't never going to create enough negative pressure in your enitre house to cause it to draw air from the outside ...... All it actually does is create just enough negative pressure at the outlet of the heat exchanger to get it to flow into the main flue ..... In fact the way they get the efficiency in an 80+ furnace like that is to restrict it so most of the heat stays in the heat exchanger rather than flowing up the chimney ..... It doesn't actually blow air out, it just creates a negative pressure at the top of the heat exchanger .... It's rated at less than 50 CFM or about twice what an 80 mm fan on your computer pushes and the reason it runs at such a high RPM is because it has to overcome a lot of static pressure
Makeup air for a furnace that size needs to be a 5" or 6" pipe (It's based on BTUs of the gas used ) and by taping off the vents on the door you risk the chance of sooting up your heat exchanger because of a messed up air to fuel ratio because it's not getting enough air ..... The 90+ furnaces have a completely different design and a much bigger blower (500 CFM high static pressure blower fans) tuned to work with a 2" PVC pipe .... It also has different burners and keeps the warm air in the heat exchanger long enough that it's barely luke warm air at the outlet allowing you to use PVC pipe for the exhaust .... It's a completely different and more complex design than an 80+ heat exchanger
Dude you going into lot of specs here, all I know is.... I sleep by open window and when it gets cold in winter it's just a inch or two open and when the furnace used to kick in I could feel the breeze coming from out side right the way until the furnace shots off, now I don't feel anything any more when the furnace turns on, so explain please. Thanks
@@VladFredK you roasted him.