Ask Me Help Desk - Interior or exterior tankless water heater

Interior or exterior tankless water heater

I'm in the process of getting quotes to install a tankless water heater. One is recommending a interior Rinnai the other is recommending an exterior Rinaai or Whirlpool unit. Both want to install on the same wall of basement crawl space. What do I need to know to make the best choice?

Depends on your fuel source, NG, LP or electric. If its NG or LP then exterior if you live in a climate that allows it. Where do you live? Venting a gas unit can add 30% to the cost of a unit. Back to you, Bob

Quote:

Originally Posted by ballengerb1

Depends on your fuel source, NG, LP or electric. If its NG or LP then exterior if you live in a climate that allows it. Where do you live? Venting a gas unit can add 30% to the cost of a unit. Back to you, Bob

Fuel source is NG, I'm located in Raleigh, NC. The local gas company is selling and installing. I spoke to the rep again and he says the cost is about the same for either, and he's recommending the interior because it eliminates the possibility of freezing and it plugs into and outlet the electrician will provide. In case of a power outage, it could get temporary power from another power source. The Gen. Contractor only does exterior units because he doesn't think anything combustible should be on the interior of the house. He said he is license to install them, but I need to verify if he is a certified installer for Rinnai. I wonder if that affects the manufacturers warranty. Do you know?
Ann

Tell us your geo-location first...

In the interim: Rinnai = Great choice ! Exterior heater is better than interior.

No combustables inside of house. I wonder how they install furnaces there? Or gas ranges, or water heaters, or gas fireplaces. Hmmmm. The more out of the weather the better. Unless you happen to live in Hawaii? Lol

Does it ever freeze in your area, if so you should go interior. That general contractor is blowing smoke.

Quote:

Originally Posted by ballengerb1

Does it ever freeze in your area, if so you should go interior. That general contractor is blowing smoke.

Yes it does freeze here, not a lot, but it does freeze.

Now your general is really blowing smoke. If it freezes it will be coldest in the middle of the night when no water will be running or getting heated. The supply line will freeze and likely burst or at least stop all of your hot water supply until it thaws. I'll bet the general is selling you his heater in store, right?

Ann: I am Rinnai factory certified installer. Your GC is not giving you correct info. Besides, Rinnai heater is an enclosed system with no burning pilot. Electric pilot activates only on demand.

Also, If there is power outage than it doesn't matter if the heater is installed on the outside or inside - you won't have power either way.

Now, If it gets cold in your area, then install the heather on the inside. No change in performance at all. Important: these heaters have very high gas consumption. Btu's for Rinnais range from about 19,000 to 200,000 Btu's per unit. In 99.9% of cases you need to run new, dedicated, gas line from the gas meter all the way to the heater. Installer has to use Gas Load Tables to determine what size of gas line he has to use. He should not take gas supply from your existing gas system inside your house for the heater won't function properly.

Quote:

Originally Posted by Milo Dolezal

Ann: I am Rinnai factory certified installer. Your GC is not giving you correct info. Besides, Rinnai heater is an enclosed system with no burning pilot. Electric pilot activates only on demand.

Also, If there is power outage than it doesn't matter if the heater is installed on the outside or inside - you won't have power either way.

Now, If it gets cold in your area, then install the heather on the inside. No change in performance at all. Important: these heaters have very high gas consumption. Btu's for Rinnais range from about 19,000 to 200,000 Btu's per unit. In 99.9% of cases you need to run new, dedicated, gas line from the gas meter all the way to the heater. Installer has to use Gas Load Tables to determine what size of gas line he has to use. He should not take gas supply from your existing gas system inside your house for the heater won't function properly.

Thanks Milo for the info. You've confirmed what my intuition has been telling me - buy it from the gas company for the expert/best installation. They are certified Rinnai installers. The good news is the install spot is on the wall inside my gas meter/line. We do get winter freezes here, so that's why the gas co. is recommending the interior unit. Plus this moves my water heater out of the garage and closer to higher points of use. Also I have read your earlier posts that the in your experience Rinnai has been a very reliable product.

Ann: if you don't feel comfortable with the guy than you can always go to Home Landing Page - Rinnai and look up another certified installer in your zip code. As far as the purchase goes: you don't have to buy it from Gas Co.. But you can purchase it yourself on line.

Good luck... and... stop by later to let us know how it went ! Milo

I totally agree with Milo on this. I have only done two installs and already know more than your general, Milo has me beat by a country mile with his certification.

Quote:

Originally Posted by Milo Dolezal

Ann: if you don't feel comfortable with the guy than you can always go to Home Landing Page - Rinnai and look up another certified installer in your zip code. As far as the purchase goes: you don't have to buy it from Gas Co.. but you can purchase it yourself on line.

Good luck ...and...stop by later to let us know how it went ! Milo

My install is scheduled for next week, I'll report back with results. Thanks! Ann