Tankless Water Heaters Inside/ Outside?

[karoc]

First GJ let me apologize for all my questions, but I value yall opinion. My 1000sq ft retirement is located in East Tx which does get some freezing temp and sometimes snow. There been times that temperatures below freezing over couple weeks but not that often. So to my question, going to install a tankless WH. I want to install it outside so that cleaning/flushing and venting would be easier. This would also increase space in our utility rm. But with freezing temperatures, even if it’s only day I’m afraid it damage tankless. I don’t know of any precautions that could take to prevent it from freezing, other than to drain it. Which I’m ok with that, if draining completely empty’s it.
There is rm to mount it inside but outside be so much better since it’s going to run off propane. Please offer suggestions, I’m sure the guys that live up north whose winters last for few months, knows how keep their tankless from freezing. Thanks guys

 

[Ton ton]

Put it inside. Yes, I do use a tankless water heater. It has a vent to the outside.

 

[mike93lx]

I know it's a thing in warm climates, but I can't get used to it. Same with load centers. Inside is what I would do.

 

[loganb]

Exterior mounted units is only a thing in southern climates. Northerner's keep it from freezing by putting it inside. You're cleaning/flushing it 1x or 2x a year...it's wall mounted and not taking up floorspace, my vote is put it inside.

 

[BrandonV]

I know it's a thing in warm climates, but I can't get used to it. Same with load centers. Inside is what I would do.

Doesn't mean it's the right thing .

I see plenty of problems in Arizona with the water heaters and panels being outside.

 

[mike93lx]

Doesn't mean it's the right thing .

I see plenty of problems in Arizona with the water heaters and panels being outside.

Its really weird watching YouTube vids of guys in Australia (I love the drain clearing stuff) and seeing tank water heaters sitting outside, plus all the drain plumbing just running down the outside of the wall. I get the appeal on heating... Why add a heat generating appliance indoors just to have to run the a/c more, but it's just odd to me

 

[BrandonV]

Its really weird watching YouTube vids of guys in Australia (I love the drain clearing stuff) and seeing tank water heaters sitting outside, plus all the drain plumbing just running down the outside of the wall. I get the appeal on heating... Why add a heat generating appliance indoors just to have to run the a/c more, but it's just odd to me

A tank water heater outside makes more sense to me. The tankless units I've come across here in Arizona always seem to have some fragile plastic part that tends to fail or leak, and it makes me wonder if they would last longer indoors.

What really baffles me in Arizona is having the air handler in the unconditioned attic. The unit sits horizontally, never draining as efficiently as a vertically installed unit. No matter how well it's sealed, it still ends up letting in debris from the outside and the attic.

The air handlers I see in garages and houses make more sense IMO. It always boils down to space I guess.

 

[u2slow]

You could build on a small shed-type addition to the side of the house for utilities, etc. Insulate it, and siding to match the house.

 

[gleman]

I wouldn't put it outside if there's a chance of freezing.

I just flushed one and have two more to do.




You only need a pump, two hoses and a bucket, so little space is needed.



Compared to a traditional heater they take up next to no space. For what they cost I wouldn't roll the dice.

Building a insulated lean-to seems costly, just for sticking it outside.

 

[Bopbop]

I design commercial plumbing systems as my day job. I have done similar exterior systems that have been installed in middle Georgia that have had no issues when properly installed. I have seen several systems installed on the Georgia Florida line that have frozen and ruptured. Some of the better commercial grade tankless water heaters have a freeze protection future which will prevent freezing. That with the exposed water pipes having self regulating heat tape and good insulation installed to the inside of the building is needed.
That being said if it was my house I would locate the heater on the interior of the house in the utility room. From there I would use the sealed combustion unit that has an air intake and exhaust. I would then pipe the intake and exhaust to a concentric vent fitting so that you only have 1 roof or wall penetration.
Check with some locale plumbers or supply houses to see which manufacturer provides the best service for your area.

 

[housewolf]

I’m a plumber and did the plumbing on my own house. I have a large attic so that’s where I put it. Even at my age (67) I’d have no problem carrying a replacement up and the old one down single-handedly.

Most of my neighbors have theirs outside

 

[mike93lx]

I’m a plumber and did the plumbing on my own house. I have a large attic so that’s where I put it. Even at my age (67) I’d have no problem carrying a replacement up and the old one down single-handedly.

Most of my neighbors have theirs outside

Attic plumbing always baffled me too. Maximizing damage when a leak occurred never really appealed.

Other than getting it out of the way, it just feels like there is no benefit and a lot of risk

 

[Axehandle2]

Just to be the contrarian in this discussion, I have mine installed outside. It was the recommendation of the plumber and the propane supplier. The contention was that for the small number of days of freezing weather we have it would not be a problem as the manufacturer says there is freeze protection circuit in the unit.
Just because I am a backup kind of guy, I did install a heat lamp at the bottom of the skirt and when we are expecting cold weather I turn it on.

 

[housewolf]

Attic plumbing always baffled me too. Maximizing damage when a leak occurred never really appealed.

Other than getting it out of the way, it just feels like there is no benefit and a lot of risk

It’s pretty common in residential in this part of the country. Overhead plumbing in commercial work is common everywhere (that I’m aware of).

FWIW; my house is foam insulated and the attic is usually within 5-7 degrees of the indoor temp. There is a pan under the WH. I got my masters Plg license in 1990 & I’m 100% comfortable with it in my own home

 

[mike93lx]

It’s pretty common in residential in this part of the country. Overhead plumbing in commercial work is common everywhere (that I’m aware of).

FWIW; my house is foam insulated and the attic is usually within 5-7 degrees of the indoor temp. There is a pan under the WH. I got my masters Plg license in 1990 & I’m 100% comfortable with it in my own home

I get it's common and am glad you are happy with that setup.

I'm just saying I don't like the idea and don't see enough benefit to justify it for me.

 

[karoc]

Thanks for all replies, which all makes sense. Inside it will be, giving me little piece of mind

 

[Jackfre]

Not sure what you are putting in but you may be able to set the unit high up on the wall to maximize storage. Whatever manuf you are going with make sure you run a two pipe system for exhaust and combustion air, especially so if the laundry is in there too. Start with the termination clearances on the vent and go from there. There is an option for you with a Rinnai model. They make a box that fits inside a stud bay in the wall and closes over the water heater. It is an outside unit but installed in the box so it is flush to the wall. I’d just put it inside though.