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Coal Boilers

Posted: Sun. Jul. 06, 2008 10:29 am
by jaysonref
lookin for a coal boiler that burns rice coal to heat 2500 sq ft garage with radiant heat in floor. lookin for in put.
jay

Re: Coal Boilers

Posted: Sun. Jul. 06, 2008 1:00 pm
by coalkirk
Harmans VF3K would do nicely, if you could get one.

Re: Coal Boilers

Posted: Sun. Jul. 06, 2008 4:10 pm
by LsFarm
What are you using to heat the garage floor currently?? How many BTU's ?? How well insulated, and how warm do you want the floor to get?? Is the floor unsulated under the slab, and is the perimeter insulated from the frost in the outside ground??

I used to heat my 2400 sq ft shop with two 40K BTU 40gallon hot water heaters.. I only wanted to keep the floor at 45-50*.. this gave me about 35-45* air temps... I used a waste oil heater to bring the temp up higher if I was going to be doing an all-day job..

So if you aren't trying to make the shop 70*, a 80-100K BTU boiler should do the job..More BTU's may be needed for keeping the shop at 'room' temperature.

Greg L.

Re: Coal Boilers

Posted: Sun. Jul. 06, 2008 10:51 pm
by beatle78
jaysonref wrote:lookin for a coal boiler that burns rice coal to heat 2500 sq ft garage with radiant heat in floor. lookin for in put.
jay
How do you do radiant floor in a slab? We're adding on to our house and this would be perfect for us!

thanks!

Re: Coal Boilers

Posted: Sun. Jul. 06, 2008 11:20 pm
by Yanche
The most common method for heating a concrete slab on grade is with PEX tubing embedded in the concrete. Warm water is pumped through the tubing to heat the slab. Many important details to follow for good performance, i.e., insulation, tubing spacing, water temperature, controls, etc. If it's not a concrete slab but, conventional sub-floor over joists, there are several methods using metal plates in the floor that are first heated by the tubing. There is even a convection system that uses the much hotter hot water like that in a baseboard radiator. This is especially good for retro fit applications or where only a single room needs radiant heat.

Re: Coal Boilers

Posted: Sun. Jul. 06, 2008 11:50 pm
by traderfjp
Insulated slippers are a cheaper alternative. :D

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 12:21 am
by Yanche
How about insulated slippers with embedded tubing, then you could just pee in the tubing and have warm feet. :-)

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 5:52 am
by LsFarm
The pee eventualy cools, and you are left with smelly, squishy slippers..

A warm slab with ceramic tile or thin wood flooring glued down is an amazing luxury.. I would NEVER build an addtion, or build a new house without in-floor heating... the cost is quickly paid back in comfort... and savings.. a room with in-floor heat will be comfortable with air temperatures several degrees cooler than a cold floor, hot ceiling room... once experienced, there is no comparrison,.

Greg L.

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 10:02 am
by jaysonref
I am an hvac contractor and the upstairs of the shop is going to be my office. the foundation and under the slab is going to be insulated. I am going to use hydro air for the second floor. and I would like to use a small indirest for demostic h20. I will keep the shop around 55 60 upstairs will be on a set back uhen not in use. in not lookin for a BTU load but more type or style of boiler. im new to coan. im puting a alaska stove furnace in my house and it burns rice coal and thats y I want to use rice coal in the boiler.

thanks for your input

jay

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 11:04 am
by Yanche
There's a radiant heat floor system that's ideal for retrofits when you have access to the floor joists. It uses the convection principle to get the heat out of the plumbing but then it's converted to radiant when it heats the floor. What's great is it use high temperature water, the same water temperature as your baseboard to radiators. No need for injection mixing, etc. It's also great for rooms like kitchens where you frequently don't have enough wall space to get the needed baseboards. Take a look at:

http://www.ultra-fin.com/

I'm currently trying to analyze the design criteria for using standard baseboard heating elements instead of the flat louvered fins.

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 11:17 am
by cArNaGe
Yanche wrote:There's a radiant heat floor system that's ideal for retrofits when you have access to the floor joists. It uses the convection principle to get the heat out of the plumbing but then it's converted to radiant when it heats the floor. What's great is it use high temperature water, the same water temperature as your baseboard to radiators. No need for injection mixing, etc. It's also great for rooms like kitchens where you frequently don't have enough wall space to get the needed baseboards. Take a look at:

http://www.ultra-fin.com/

I'm currently trying to analyze the design criteria for using standard baseboard heating elements instead of the flat louvered fins.
I wonder how that will work under a carpeted floor?

Re: Coal Boilers

Posted: Mon. Jul. 07, 2008 11:42 pm
by Yanche
Floor coverings have a major effect on the thermal performance of any radiant floor heating system. The heat output from floors having floor coverings over 2.0 will be very marginal. All radiant floor designs should have a careful design analysis. Typical R values for floor coverings are:

Bare - 0
Asphalt or rubber tile - 0.05
1/8" sheet vinyl - 0.20
3/8" ceramic tile - 0.30
1/4" carpet glue down - 0.95
1/4" carpet over 1/4" pad - 1.44
3/4" marble - 0.42
3/8" hardwood - 0.52
1/2" hardwood - 0.70
3/4" hardwood - 1.05

Re: Coal Boilers

Posted: Tue. Jul. 08, 2008 8:11 am
by Freddy
LsFarm wrote:
I would NEVER build an addtion, or build a new house without in-floor heating...Greg L.
So true! Even if you want a carpet with a pad, put the infloor to it and have a bit of baseboard for those extra cold days. We have some infloor, some not. One place in a carpeted hall there is a small area of tubing. I''m sure it doesn't give off a lot of heat, but if you have bare feet on the caret you sure can tell where the tubing is.

Re: Coal Boilers

Posted: Tue. Jul. 08, 2008 10:34 am
by LsFarm
Looking at the list of insulation factors that Yanche posted [thanks John], I'm surprised by the fairly high factor for ceramic tile, .30. And also surprised by the relatively low factors for wood flooring. .50 or so.

I would have thought that ceramic would be near to 0, since it is cemented to the concrete floor,, and is solid minerals.. like concrete.. But wood is full of air spaces, and does provide a fair amount of insulation factor... Maybe it's the fact that it is dense wood, not soft pine...

Anyway,, when I'm standing on my heated ceramic floor in front of the bathroom sink and mirror,, I shuffle around till I find the warmest spot to stand on,, a warm floor is an amazing luxury,, especially when you get out of the shower..

Greg L

Re: Coal Boilers

Posted: Tue. Jul. 08, 2008 10:39 am
by coaledsweat
Put the heat tubing on top of the subfloor and cover it with cement if you want thick carpets and a pad. That is really how it should be installed, especially with new construction.