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Re: Add a Cold Air Return?

[QUOTE=jbened02;132217 Running the blower seems to just blow cold air out of the vents in the living room so I have since turned it back to auto.

Running the blower on low speed will reduce the drafty effect that you are experiencing. Furnace blower motors have "speed taps" that can adjust the fan speed, and can be set up so that the heating mode is one speed, cooling mode a different speed, and "fan on", another speed.

You may also do what one other poster did, and that is to try directing more of the supply air to the lower level by adjusting the flow at the registers. Be careful, however, not to throttle the flow too much, because overdoing it may result in insufficient airflow across the heat exchanger, which will cause it to overheat. This can damage the heat exchanger over time.

How to know if it's OK? After the furnace has been heating for about 5 minutes, check the air temperature in the duct at the return duct as close to the furnace as you can, and check the supply temp near the outlet of the furnace--the difference in these two temps should not be much more than about 65-75 degrees for most furnaces. The furnace manual will give the acceptable range.


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