Radiant Floor Heating Questions - HVAC - Page 3 - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 03-02-2010, 06:12 PM   #31
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,471
Rewards Points: 4,588
Default

Radiant floor heating questions


Quote:
Originally Posted by secutanudu View Post
An HVAC guy I know told me I can use something called "onyx" tubing to run the full 180 degree temp. I don't have hardwood floors, this will just go under the tiled bathroom.

Maybe i;m better off with a small 3' baseboard plus line voltage electric under the non-shower portions of the floor?

You can run hpex at 180F also. Its not the tubing that is the problem.

Its the quick temp swing that you can get from the floor using high water temps.

The heat has to transfer from the pex to the joist, to the floor. So the joist become a lot warmer/hotter then they need to by the time the floor gets warm/hot enough. The stat stops calling for heat. But the joist are still putting more heat in the floor. So the room ends up over heating.

Advertisement

beenthere is offline   Reply With Quote
Old 03-02-2010, 07:45 PM   #32
Electric Radiant Heating
 
warmsmeallup's Avatar
 
Join Date: Apr 2008
Posts: 205
Rewards Points: 150
Default

Radiant floor heating questions


Quote:
Originally Posted by secutanudu View Post
What manufacturer do you recommend? I have a 5'x6' bathroom with a 3x3 shower, so 39 sq feet. Any estimate on how much the supplies would cost to heat a room that size with low voltage? Just one outside 6' wall that will have R13.
Sorry I haven't answered your questions. I've been working.

The only low voltage system you can use to heat both the floor and shower is Heatizon Systems' Floorizwarm Tuff Cable. The kits come with the cable, clips, digital programmable thermostat with in-floor sensor and the transformer. You will also need to buy (1) cold lead splice kit to be able to cut the element and 'jumper' it through the curb into and then back out of the shower.

As for the size, I need you to clarify if the dimensions you've given (5' x 6') are the total bathroom or the actual open floor dims? Also, the 3 x 3 shower is the total shower, right? You need to deduct the (approx) 1sf for the drain area.

As for primary heating, whether you use electric or hydronics, if you are planning on making the radiant heat your only source for heat, you should do a heat loss calculation. Once you have the load numbers, you design the system to generate enough btu's (or watts) to much more than replace what you are loosing. Most important thing to keep in mind when accomplishing a HLC; garbage in, garbage out!

You asked how hot the element gets. The element doesn't get hot and then wait for the floor to catch up. Since the element is embedded in the mortar, the mortar (or SLC/Thinset, etc) will heatsink the heat off the cable and make it all heat up evenly. The standard set back is about 7 -10 degrees. The tstat regulates the floor temp.
__________________
www.comfortradiant.net

Last edited by warmsmeallup; 03-02-2010 at 07:48 PM.
warmsmeallup is offline   Reply With Quote
Old 03-02-2010, 08:57 PM   #33
Just call me Andrew
 
Join Date: Mar 2009
Location: Albany, NY
Posts: 2,258
Rewards Points: 1,012
Default

Radiant floor heating questions


Great info, thanks. I should have been more accurate with my numbers. Here's a to-scale picture of what my bathroom will look like (1"=1'). I just talked to the guy at the pluming supply shop...my house has mostly radiators, some baseboards, all on the same zone. He said this is not ideal, since the radiators eat up a lot of hot water.

He told me for my bathroom (40 sq feet)...NORMALLY I'd need a 3-foot baseboard, but I'd need to oversize it since my zone also includes radiators. My current thinking is doing a 4-5 foot radiator for general room heat and line-voltage electric for everywhere but the shower. If the 4-5 foot radiator doesn't cut it, I can easily supplement it with the floor heat.

Ideally I'd like the floor heat in the shower too....so I need to look into pricing it out, but that's my thought for now.
Attached Thumbnails
Radiant floor heating questions-bathroom2.jpg  
__________________
Andrew

secutanudu is offline   Reply With Quote
Old 03-03-2010, 05:52 PM   #34
Electric Radiant Heating
 
warmsmeallup's Avatar
 
Join Date: Apr 2008
Posts: 205
Rewards Points: 150
Default

Radiant floor heating questions


I can't print that to any kind of scale. You'll need to measure the exact open square footage you wish to cover. Give the room and shower separately. I can then advise you what you'll need (low and line voltage) but you'll have to shop for it elsewhere. This forum is for informational use only.

Measure it so that you cover 3" - 6" into the toilet. I wouldn't want your toes to be cold!
__________________
www.comfortradiant.net
warmsmeallup is offline   Reply With Quote
Old 03-03-2010, 09:01 PM   #35
ink
DIY Enthusiast
 
ink's Avatar
 
Join Date: Jan 2010
Location: Maryland
Posts: 114
Rewards Points: 75
Default

Radiant floor heating questions


I was told that if you wanted a warm floor for a warm floor, electric is probably better. If you want a floor as a heat source, then hydronic is the way to go.
ink is offline   Reply With Quote
Old 03-08-2010, 02:04 PM   #36
Just call me Andrew
 
Join Date: Mar 2009
Location: Albany, NY
Posts: 2,258
Rewards Points: 1,012
Default

Radiant floor heating questions


I have decided to go with electric floor heating. I was thinking of using SunTouch shower-approved elements. They come in both mat form and loose wire that you stick to the floor with double-sided tape. Are these products good?

Here is my bathroom. I plan to heat both the orange shaded floor and the blue shaded shower.

Any recommendations?

Thanks.
Attached Thumbnails
Radiant floor heating questions-floorheat.jpg  

Advertisement

__________________
Andrew


Last edited by secutanudu; 03-08-2010 at 02:15 PM.
secutanudu is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Radiant Floor Rebuild kiwegan HVAC 15 02-20-2010 04:07 PM
Hydronic Radiant Floor install questions ink HVAC 9 01-10-2010 10:34 AM
steam v. hot water, radiant sub-system Lor HVAC 1 06-11-2009 04:58 PM
Installing pex radiant floor heat, questions. iMisspell HVAC 27 01-15-2009 08:03 PM
Radiant Floor Heat (ongoing questions) iGotNoTime HVAC 7 08-23-2007 04:55 PM




Top of Page | View New Posts