Tankless water heater – mount inside or outside?
user-6458536
| Posted in General Questions on
I am in middle of a 6000 sq ft home build in Alabama. Will be using 2 tankless water heaters. I have space available to mount inside attic but could do outside. Appearance wise, it would be nice to be inside so don’t see on outside of house.
Should I mount units inside or outside? Seems like being inside and not being exposed to the elements outside would be better. However, maintenance appears to involve annual or so flushing which would be a nuisance to haul the solution and equipment into attic. Note, I typically do these maintenance items myself so don’t want it to be a real pain to do.
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In a 6000' house you should be able to find some reasonable location(s) to mount a tankless(es) indoors, even if you have to design a small utility-closet type space. They often fit pretty comfortably above a clothes washer or dryer or tub-sink in a laundry room, but there are lots of indoor options other than throwing it up in the attic where it's out of sight and easy to ignore until something goes wrong.
A pair of gas fired tankless units will often blow the BTU budget on a typical gas service & meter, so pay attention- you may have to upgrade the service to get them to both work reliably at high fire at the same time.
Dana, et al, so should I try to mount them inside the house (attic, closet) or is outside just as good? Why? Attic will be spray foamed. In Alabama, our winters are not bad but on occasion will get into low 20s or colder.
Outside mounting is popular in Japan & Korea or California condominiums due to the diminutive sizes of the average homes- every square foot of floor & wall is needed for other purposes. Clearly a 6000' house doesn't have that problem.
Mounted indoors it is better protected from the elements: It won't freeze up and break the heat exchanger during a Polar Vortex cold snap, can't be taken out by flying debris during a hurricane, hit by a car or ground maintenance equipment, etc.