New high-efficiency gas furnace, old hot water tank - any issues?

I've replaced my 82% efficiency gas furnace to a new 93% efficiency model. Prior to this my old gas furnace and my hot water tank were both vented through the chimney. Now, only my hot water tank is vented out the chimney, while my new furnace is vented out the side of the house through PVC pipes.

Are there any issues with having the hot water tank still use the chimney? I didn't think so until I saw this article. I'm not an HVAC person so I don't fully understand what is the issue with "Now the hot water tank has to heat up that big chimney all by itself".

I don't know the specs of the hot water tank but I believe its around

13 years old.

Here's the full paragraph:

"Another hot water tank issue is when you switch from a conventional gas furnace and hot water tank to a new, high-efficiency sidewall vented furnace. Now the hot water tank has to heat up that big chimney all by itself, and you probably will have to pay for chimney relining. It is often better, when choosing a chimneyless furnace, to switch your hot water tank to sidewall venting at the same time and seal the old chimney closed. However, sidewall vented hot water heaters are more expensive than conventional hot water heaters and can be noisier."

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Reply to
jonny_rizzo
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Greetings,

a) don't worry about it unless there is an actual problem created b) there probably won't be a problem c) make sure you have a carbon-monoxide detector installed in your basement

Hope this helps, William

Reply to
William.Deans

yes there are issues., there is also a kit made for this purpose. your installation contractor should have done this for you.

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Reply to
hvactech2

It's been two years since I put in a high efficiency furnace and still have just my hot water vented to the chimney. My initial concern was whether or not the snow would clog the chimney cap resulting in a back flow of the exhaust gas into the basement. Just hasn't happened--the chimney cap is always free of snow and the chimney, at least to date, doesn't show any signs of any problem. MLD

Reply to
MLD

I heard the same thing from the house inspector, as well as a chimney cleaning guy and the HVAC people I use. It makes sense. The liner's being installed in September.

Reply to
Doug Kanter

they put a sleeve inside the chimney for the water heater. that is what they did to my chimney. cut the moisture down and saves the mortar.

Reply to
jdk

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