HVAC question.

Discussion in 'The Garage' started by miketx, Jun 2, 2018.

  1. miketx
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    miketx Diamond Member

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    My water heater went out and we swaped it out and found that the vent on the old one vented into the open attic. The vent for the heater is only about a foot away and was wondering if it would hurt anything to tie the water heater into this vent so it would vent outside?
     
  2. 007
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    007 Charter Member Supporting Member

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    One would effect the venting of the other though. The vent pipe size matters. One pipe's venting gas would actually PULL the flow of the other. Not sure that would be a good thing or not, but I'd think you'd have to at least double the size of the vent pipe past where you'd join the two.

    Just my thoughts, probably best to ask an HVAC guy.
     
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  3. Crepitus
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    Crepitus Gold Member

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    Depends on the size of the vent. You need to do something though, the gas water heater makes carbon monoxide.
     
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  4. evenflow1969
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    evenflow1969 Gold Member

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    With out knowing particulars I can not say for sure, how ever most vent pipe installations involve these tow pipes joining just a two to three feet from the furnace. Assuming the pipe is large enough to hold both exhausts should do fine in the same pipe. Try it and if you feel kick back flow, extend the current pipe in the attic to go above roof level. Do you know what size pipe it is?
     
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  5. miketx
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    miketx Diamond Member

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    Both pipes appear to be 4 inch.
     
  6. evenflow1969
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    evenflow1969 Gold Member

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    How many BTU furnace and water heater? Even if the pipe is not big enough, I think it is unless you are in an unusually large home! There are inline fans you can install if the pipe is not flow rated for the amount you are giving it. I highly doubt you will need it. Four inches should be plenty in most residential applications
     
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  7. Moonglow
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    Moonglow BANNED

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    Is it electric or gas?(tee-hee)..
     
  8. miketx
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    miketx Diamond Member

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    I dont know the btu rating but it's a small house.
     
  9. miketx
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    miketx Diamond Member

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    I dont know.
     
  10. Moonglow
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    Moonglow BANNED

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    Open vent should work fine.
     
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