Furnace is venting under deck

Old 08-13-13, 06:58 PM
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Furnace is venting under deck

So my furnace has its air intake and exhaust underneath my deck... I think what had happened is the previous home owner installed a deck then never bothered to move the pipes. Under the deck there is about 3 feet clearance from ground to the deck boards. Instead of moving both intake and exhaust together can I just move the exhaust to another side of the house and leave the intake under neath the deck? I've noticed last winter the snow does not accumulate at all so it's sheltered.

The current length of the intake and exhaust is about 14 feet each way to under the deck. The new proposed exhaust pipe length would be about 30 feet. If I ran both intake and exhaust to the same place it would be 30+30 = 60 feet of total pipe length... I was thinking If I used the current intake pipe which is 14 feet and then install the new exhaust 30 feet it would be about 44 feet in length. Currently have 3" PVC. What exactly are the limitations on how long the run can be?

any suggestions of what I should do?

Old 08-14-13, 07:17 AM
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Leave the intake, more the exhaust. Check with the installation guide for the system in regards to max. length of the combustion air piping.
Old 08-14-13, 07:09 PM
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Both the intake & exhaust need to be on the same side of the house. The reason for this is when it's windy, both pipes see the same pressure & you'll be far less likely to have pressure switch problems.

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