Plumbing in the Home/water heater replacement


My current water heater needs to be replaced, and I am trying to determine the best replacement. I have had 3 plumbers out to give quotes, and they all three gave different recommendations.

My current heater is a natural gas Rheem 75 gallon with a power vent, and the exhaust vent pipe is 4" PVC, about 25' long, with a slight upward pitch. My first inclination was to get a 40 gallon natural gas tank, but replacing the power vent was going to be extremely expensive. However, one of the plumbers said that he could install a gas fired tank without a power vent, and use the same vent run (although replacing the PVC with metal).

So, the question is this: does this sound safe? A gas fired tank with a (nearly) horizontal 25' exhaust vent to the side of the house? Also, do you have any opinion of State water heaters?


I would definitely not install a natural gas fired heated the way the you have described. It is NOT safe. Water heaters need to be vented above any doors or windows and above any roof eave. Carbon monoxide is nothing to take lightly.
Here are the options I would recommend to my customers.
1. Replace heater and power exhaust as existing.
2. Install a direct vent heater with a side wall vent.( you would have to reroute water piping)
3. Install a standard Nat gas heater and install a double wall vent chimney up the side of the house and above the roof line per standards and codes.
4. Install a masonry chimney (expensive)
5.Install an electric heater(absolute last resort)

My  preference is a metal double wall vent up the side of the house. You can use single wall inside in some locales, but I prefer double wall from the heater all the way up to the roof.
25 feet is doable as long as you have the pitch and it's supported properly

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Jay Nicholas


Plumbing & Heating (warm air, hot water & steam heat)


40 years in the business, 40 years as a lic. master plumber in NY State. Retired

Graduated Magna cum laude at the School of Hard Knocks

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Commercial, residential and light industrial. You name it ...I have probably worked on it

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