How to drain high efficiency furnace condensate without an internal drain
We’ve had 5 estimates for a high efficiency furnace to replace our 30 yr old beast. Two guys said no problem. Then the final 3 raised questions about the condensate. We do not have a sump pump or utility tub in the basement for drainage. One guy said we couldn’t vent outside because it would freeze ( we live in SE Pennsylvania), so we’d have to put a trap on one of the plumbing lines and divert it there. Second guy said no to the trap because it’s against code and yes to going outside because only a short piece of the pipe would be exposed outside and freezing wouldn’t be a problem. Third guy said we are not candidates for the high efficiency because of the drainage issues and we’d have to go with an 80% chimney vented furnace. We are more confused now than when we started. How can so many HVAC guys have differing opinions ( and two not even see a problem)? Not sure which direction to go..do we keep getting estimates until we get the majority to agree on inside drainage/outside drainage/80%? Any advice would be greatly appreciated.
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Tammy, call your building department. They will know the rules and the norm for where you live.
Where I live we dump water both ways, it is easy to set up an outside dump that is insulated and will fully drain so as not to freeze closed. Some sewer districts do not allow sumps to drain into them. That is something you can call to find out about.
I ran into the same issue with where to drain. I contacted the inspectors in town and even sent a pictured of my plumbing stack in the basement. I added a wye with a Studor vent then j trap. There specific specs on how far the vent had to be from the wye, then the trap from the vent and how high the vent needed to be above the ine. I now have my furnace/ac condensate pump and another for the condensing water heater both drain to that location. I highly recommend not going outside. Its another hole in the wall, the condensate is very acidic so have to beware what it touches, and if short it is draining near your foundation.