**Help**Outdoor boiler to supply plenum

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New Member
Nov 4, 2020
Ferrum va
Hello I just installed a outdoor boiler my only problem is trying to figure out a way to connect to my hot air furnace inside. The indoor hot air unit is old but works but the problem is my supply plenum is 15wide by 10thick and 26 long there is no water to air heat exchanger that size. Is there away I can make somthing work here. My house is 1200sqft


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I can't see what's going on on the back side. You're going to have to bend a transition wider, but I don't know how much room you have to work with.
The cfm of the blower would affect how large I would try to fit in, and if it has A/C.
You can get 15x15 I think and taper it wider.
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Yes I will have to try and get a better view of the back side it does have a/c but the coil appears before my blower . I’ve read that some can be in the plenum. This is a older unit under the house I’ve been trying to learn as much information as I can on it


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Pretty standard configuration.
What's the model number of the outside unit? That might give a clue on how many tons of AC.
Model number is 40AQ030310BU
Carrier brand unit


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Last edited:
I think it's a 2½ ton. 15x15 coil should be fine.