Heater under a deck

[CJadamec]

Personally I would do everything I could to keep the heater away from the deck area. While you may be fine from a safety stand point. When that heater is running you will like hear, smell, and probably feel the exhaust if you are on the deck. If for nothing else it is going to be a distraction from what looks to a beautiful and peaceful pool area. You've got plenty of space it wouldn't be a huge deal to stick the heater around the corner of the house. Aesthetically I don't think you will be happy with a vent kit sticking out off the back of the heater.

 

[PoolGate]

Personally I would do everything I could to keep the heater away from the deck area. While you may be fine from a safety stand point. When that heater is running you will like hear, smell, and probably feel the exhaust if you are on the deck. If for nothing else it is going to be a distraction from what looks to a beautiful and peaceful pool area. You've got plenty of space it wouldn't be a huge deal to stick the heater around the corner of the house. Aesthetically I don't think you will be happy with a vent kit sticking out off the back of the heater.

It is what it is at this point the plumbing is done and the equipment is placed. There really wasn't any other area to put it other than about 6 feet away outside that area which really wouldn't make much difference. At least here it is protected from the elements and I will put lattice work in front of it to hide all the equipment. The gas guy charges by the foot as well so to move it on the other side of the deck for instance would be around $2k more in gas costs not to mention the extra costs to run electric.

The beauty is that it is a gas heater. Once up to temp we can shut it down (if needed) and the pool will hold its temps while we enjoy the pool. I would have loved to put it on the side of the house but I don't think they could have run the pool plumbing another 20 feet further from the pool.

 

[ps0303]

I would still vent the system out from under the deck.

 

[PoolGate]

I went to look at my neighbors 400btu NG Hayward heater today and watch it run - it is an older (8 year old) very large heater 2-3x bigger than this one. If you put your hand within 8" of the exhaust, it is very hot. 12" not too bad, any further you can't feel it barely at all. Does anyone who commented above actually have a natural gas heater? I'd like some first hand and not anecdotal evidence.

 

[Ted527]

You might not feel much heat from the exhaust but the fumes will rise up through the deck above.

 

[ryan-california]

Make sure it is vented away from where you will be. Carbon monoxide will dissipate well outdoors, but coming at you in full concentration from the heater is asking for trouble. If it vents out the side someplace away from usage areas, it *may* be okay. Definitely check local regulations

 

[JamesW]

Maybe you could rig up some sort of fresh air delivery system for people using the deck.

Maybe you could have masks with fresh air pumped through hoses so that people on the deck get fresh air.

It might be worthwhile to have guests sign a waiver acknowledging the risk of carbon monoxide poisoning when using the deck. That might reduce your liability if someone claims to have been injured by carbon monoxide.

 

[GWT]

I have 106a propane heater under my deck, there is no exhaust and it is under the minimum clearance, I put a heat shield under deck just for safety reasons but have had no issues what so ever yet. It is warm over the unit on the deck, but I can reach in and hold the joists, structure with no harm from heat to my hand it does get hot but if it's not hot enough to burn you the deck is fine.

Now on for the monoxide issues in an outdoor area of most any kind if not enclosed you will be fine! Ask me how I know? I own HVAC company and have done this work for 31 yrs. I can't imagine someone being gassed to death in an outdoor environment especially from pool heater under a deck with his specks!??

i would not worry about it to much like I said mine has been running all summer and it is actually enclosed under deck my deck is enclosed on the sides with decking boards and split face block columns floor is warm over unit but I sat over it for 30 minutes few days back when I got out of pool and temps had dropped the heat was nice no doubts.

 

[ryan-california]

Lol

Our tankless water heater is just outside one of our sliding glass doors. It vents up, and our CO detector has never complained. If vented properly you should be fine. Just make sure it's to code

 

[JamesW]

I have 106a propane heater under my deck, there is no exhaust and it is under the minimum clearance, I put a heat shield under deck just for safety reasons but have had no issues what so ever yet. It is warm over the unit on the deck, but I can reach in and hold the joists, structure with no harm from heat to my hand it does get hot but if it's not hot enough to burn you the deck is fine.

Now on for the monoxide issues in an outdoor area of most any kind if not enclosed you will be fine! Ask me how I know? I own HVAC company and have done this work for 31 yrs. I can't imagine someone being gassed to death in an outdoor environment especially from pool heater under a deck with his specks!??

i would not worry about it to much like I said mine has been running all summer and it is actually enclosed under deck my deck is enclosed on the sides with decking boards and split face block columns floor is warm over unit but I sat over it for 30 minutes few days back when I got out of pool and temps had dropped the heat was nice no doubts.

The heater definitely has exhaust. The level of carbon monoxide might not kill someone but it might cause adverse effects.

The major manufacturers all say not to put the heater under a deck. Maybe contact the heater manufacturer for their opinion of the installation.

 

[LFrankow]

In the end it will be up to the authoritative authority/inspector.
The products of combustion when burning a properly adjusted burner are carbon dioxide and water vapour. You may run into CO issues as the burners age/get dirty etc. but if see a nice blue flame you will get carbon dioxide and water vapour.
The clearances to combustables are listed on the rating plate inside the door, those must be adhered to.
The inspector may or may not require a remote chimney, which as you say you are more then willing to add.
IF you at a later date decide to enclose the area, that is a whole nother thing.

 

[PoolGate]

In the end it will be up to the authoritative authority/inspector.
The products of combustion when burning a properly adjusted burner are carbon dioxide and water vapour. You may run into CO issues as the burners age/get dirty etc. but if see a nice blue flame you will get carbon dioxide and water vapour.
The clearances to combustables are listed on the rating plate inside the door, those must be adhered to.
The inspector may or may not require a remote chimney, which as you say you are more then willing to add.
IF you at a later date decide to enclose the area, that is a whole nother thing.

Again, there is no inspection for the heater or any of the pool equipment.

Manufacturers look for liability. The easiest answer is to say not to do it. I don't blame them. But one sized fits all "don't do it" isn't targeted at my build of a 12 foot space fully open to the environment it is more targeted at someone with 10" above the heater in an enclosed space. The gazebo/deck, 8 feet above, also has outdoor carpeting on all surface areas. This is just like an inside rug accept it is made to withstand the elements. Almost nothing gets from below to the deck via the air unless it comes out the side, then up, then makes a 90 degree turn to land on the deck or gazebo area. Yes, kind of like that magic bullet of the Kennedy assassination!

I did contact Jandy to ask their advice with pictures and measurements of my build. So far they have not responded. My guess is when they do, they will simply point to their lawyer blessed warnings in the installation manual (as expected).

Thanks GWT for your post that is very helpful!

 

[PoolGate]

I was just reading an article about "carbon monoxide" myths. Very interesting. I will test what is coming out of the exhaust on the heater when it is running but I don't think any CO is produced at all.

 

[JamesW]

If you get a clean blue flame, there should be minimal carbon monoxide. A blue flame is hotter and is the result of complete combustion. The carbon picks up two oxygen vs one in the chemical reaction.

A red, orange or yellow flame is the result of incomplete combustion and indicates that carbon monoxide is being produced.

 

[PoolGate]

If you get a clean blue flame, there should be minimal carbon monoxide. A blue flame is hotter and is the result of complete combustion. The carbon picks up two oxygen vs one in the chemical reaction.

A red, orange or yellow flame is the result of incomplete combustion and indicates that carbon monoxide is being produced.

That same article also says this is a myth.

Myth-1 - Heat Exchanger Cracks | CarbonMonoxideMyths.com

 

[JamesW]

What happens if the heater is not running right and creates a lot of carbon monoxide?

 

[PoolGate]

What happens if the heater is not running right and creates a lot of carbon monoxide?

That could happen to any gas heating product. Being that it is outside the house in a wide-open area any CO produced would dissipate almost immediately.

 

[Ted527]

That same article also says this is a myth.

Myth-1 - Heat Exchanger Cracks | CarbonMonoxideMyths.com

Crack in a furnace will not cause CO production, a flame not burning properly will 100% of the time.

In the end it's your pool and your family on the deck over a fuel burning appliance.
If you're comfortable with that after all the advice saying not to do it then good luck.
I did hvac for over 40 years, it is not something I would be comfortable doing.

 

[PoolGate]

So an epilogue here as I turned my heater on this week for the first time. It has been running now around 5 hours straight. I took CO readings at the unit and got a max of 5 right out of the exhaust when I first turned it on. I then went up to the deck and took readings along the way. It went down to 0 around 5 feet from the heater. I sat the CO detector on the deck above in various locations for 1-2 hours at a time. So far no location has any readings at all - the detector shows a constant 0 reading. Wind is almost 0 during most of the test but recently has kicked up just a bit. I want to get worst case scenarios with no wind so I will be testing whenever we are in the doldrums.

I will take it back to the heater later on and see if I still get any reading coming out of the heater it is possible those initial readings were because of the first time firing up.

I think I will move the exhaust anyway since I did get the relocation kit and you can feel the heat blowing around that area where the heater is located. There is also an odor but this could be the new components burning off. I'll move it up and over to the side of that area.

 

[Leebo]

PoolGate,

End of the day it’s your pool and your call where to install your equipment. The two users I personally trust the most on TFP concerning heaters BOTH agreed that it’s NOT a good/safe idea to install a heater under a deck......as does the manufactures instruction manual.

I’m all for an open discussion concerning many topics, but ones where a users health is in question we need to refer to what’s known. Incorrectly installed heaters CAN kill you. I see no reason to continue to justify or research this at this time. It’s a bad idea and is NOT one TFP would recommend.