Using a domestic water heater for slab heating


  #1  
Old 11-21-08, 12:49 PM
B
Member
Thread Starter
Join Date: Nov 2008
Location: NW Minnesota
Posts: 6
Received 0 Votes on 0 Posts
Using a domestic water heater for slab heating

I am aware that people have used a regular domestic water heater instead of a UL listed boiler to supply heated water to a closed <circulating water> slab heating system....
Well, This may do the job quite well, and replacement heating elements would be easy to find in most hardware stores.
But,, is this particular use of a water heater a violation of any specific electrical (2008??or??) or plumbing codes??
 
  #2  
Old 11-21-08, 01:02 PM
I
Forum Topic Moderator
Join Date: Feb 2005
Location: Near Lansing, Michigan
Posts: 10,941
Received 45 Votes on 43 Posts
Generally using any appliance contrary to the manufacturer's labeling is considered a code violation. The biggest problem I can see with using a standard WH for radiant heating is that the WH is not designed for continuous operation. They're really only designed for a peak hour or two per day; not 24/7 hot water supply.
 
  #3  
Old 11-22-08, 01:01 AM
F
Member
Join Date: Mar 2006
Location: NE Wis / Paris France{ In France for now }
Posts: 4,807
Received 2 Votes on 2 Posts
The other thing is that the wattage is very low on the water heater compared true boiler { 1500 watt will crank out about 5100 BTU so 4500 watt element will dish out about 15,300 BTU } and most resdential waterheater are not designed for contionous operation at all.

One of my customer done that and the result was very terrble with it { he have both gaz and electric waterheater running that time and the bill was just insane after he covernted to true boiler the bill drop down a bit }

Merci,Marc
 
  #4  
Old 11-22-08, 06:37 AM
R
Member
Join Date: Apr 2007
Location: Near Buffalo, NY
Posts: 4,233
Received 1 Vote on 1 Post
I have two friends who own houses with slab heat. Both of their systems use glycol instead of water. How would this affect the use of a hot water heater?
 
  #5  
Old 11-23-08, 12:13 AM
B
Member
Thread Starter
Join Date: Nov 2008
Location: NW Minnesota
Posts: 6
Received 0 Votes on 0 Posts
Thanks for your responses

Our local sad and bad stories about using a regular water heater have far outnumbered the good reports.
Locally, I have inquired with three electricians, my local power cooperative, the county electrical inspector, and two business places that operate hot water slab heat systems...All seven of these folks express favor of the tankless boiler system....and shared some real monster stories about some of the water heater systems they had dealt with...

In the past years, I have seen "specially equipped" slab water heaters advertised in our local cooperative's monthly newspaper..These were spendy; around a thousand bucks several years back.... I have not seen them advertised for some time...When I was asking around, nothing good was said about these units, either...

The tankless heater, ((with it's ready plumbed panel containing a pump, expansion tank, gauges, etc,)) really looks like the winner....What I am after is a 120degree heating source for a 28x56 heated shop floor, maintained to around 45degrees...A 7K boiler should be able to handle this job.???....For the past two years, This same shop has been heated by a 7.5K electric garage heater;;; this same heater can be used for supplement heat for my immediate work area
when I am out there working...I am very much open to recommendations...Thanks
 
  #6  
Old 11-23-08, 08:50 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 14,964
Received 595 Votes on 511 Posts
I hope you check back. Check out this site: Radiant heat, do-it-yourself energy efficient heating
I have some friends that use thier gas water heater for their in floor heat and it works quite well. Not sure where they got theirs ( I think it was Worsbo(sp) ) but this site seams like what you are looking into.
 

Last edited by Tolyn Ironhand; 11-23-08 at 09:37 AM.
  #7  
Old 11-23-08, 04:34 PM
F
Member
Join Date: Mar 2006
Location: NE Wis / Paris France{ In France for now }
Posts: 4,807
Received 2 Votes on 2 Posts
In case some reason if you can not go with slab route there is a low profile garage heater I know they come in 3 or 4 diffrent size the smallest one IIRC I think about 45 KBTU size but 70 KBTU is most common size I do see in my area that will work pretty well for med to large 2 car garage size for larger garage there is a bigger unit or go with infrera { spelling } tube heater those heater work very well too.

If you have more question just go by HVAC section in our forum one of our members and Moderators can help you more on the matter.

{ to find HVAC section just scroll down more lower }

Merci,Marc
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: