Low Temp heat emitters source

[peakbagger]

After taking a hydronics course, its obvious that I need to yank my baseboard and go with low temp emitters as I should be able to increase my effective storage capacity by running the emitters at a far lower temp then my Slant Fin baseboard. Sure the baseboard puts out heat at low temps but at some point the installed footage means that the system cant keep the rooms warm. The old Pex Supply (Supply House now) has some lines of emitters but I am curious if anyone has found any other good sources that direct sell to the public? Houseneeds in VT lists some lines but its all special order and traditionally their pricing isn't great on special orders. Much of the equipment I run into is only sold through distributors and the markup makes it pretty pricey (in general it looks like its about 5 to 10 times more expensive than baseboard). Give the level of talent in northern NH for heating systems, I expect 90% of the installers really have no use for low temp emitters as they mostly do baseboard with a couple of zones on a standard oil boiler so buying local is not an option.

 

[TCaldwell]

Last weekend I removed the 31 ft of slant fin, piped series that was struggling with supply water under 140 deg. This is a living room, 16ft cathedral ceiling and lots of glass on the south facing wall, adjoining kitchen with 8ft ceiling, totals out to 800sqft. The room configuration, wall spaces, window heights didn't configure well to cast iron rads or panel rads, I didn't want to spend the money for cast iron baseboards, I went with the smith's environmental double element baseboard, 40ft total and piped it supply on top and reverse return on the bottom. Possibly at 120 deg the slant fin was producing 300btu/ft, I believe the smiths is double that. Last night was cold, single digits and windy, typically to compensate for this room in weather like this I'd fire at 150deg to try to hold 73 deg, the smiths held the room at 73, and was still holding at when I fired at 130deg this morning. Overall so far I'm impressed, I ordered last wed, Thursday they were at my doorstep, Sunday they were running. I thought the cost was reasonable, 28$/ft.

 

[velvetfoot]

I can't really help you, but I looked into low temperature baseboard a couple years ago. At that time Heating Edge was best, (broken link removed to http://www.wardheating.com/pages/hydronics/-new--low-temperature-perimeter-heating) . There might be others selling similar products now, including Slant Fin, since it helps the mod-con boilers work to max efficiency. Are you sticking with baseboard?

Wow: As I was typing...

 

[velvetfoot]

Here is a chart I made. It's a couple years old and outdated I'm sure.

 

[velvetfoot]

and piped it supply on top and reverse return on the bottom.

So, was that the way the stuff you took was piped, or did you change things?

 

[maple1]

Question: are there some low temp emitters, that have a max supply temp spec?

Low temp emitters are great for getting heat out of cool water - but if they are limited in how hot the water can be that's going into them, you might come up short on the recovery aspect. If recovery is a particular concern.

I would like more low temp emitters in my system, but at least my oversized Slant-Fin does have some recovery horsepower to it if I want to send hot water to them. I don't think it would matter to most types but not sure - and that is one of the drawbacks to low temp radiant in-floor, it only likes water of a certain hotness so recovery is slow.

 

[peakbagger]

I would like to go radiant wall mount emitters. My floors are not well set up for conversion to tubing and based on the course I took, tubing has its limitations unless the house was designed for it, plus I do a lot of setback in the house zones so I want reasonable response. I have a couple of spots where putting tubing in walls would be great but not in the mood to drywall, although my bathroom may get it at some point.

 

[JohnDolz]

I would like to go radiant wall mount emitters. My floors are not well set up for conversion to tubing and based on the course I took, tubing has its limitations unless the house was designed for it, plus I do a lot of setback in the house zones so I want reasonable response. I have a couple of spots where putting tubing in walls would be great but not in the mood to drywall, although my bathroom may get it at some point.

I probably should remain silent as most of you have been on the other thread but while I agree with the value of low temp emitters I believe the better place to start is with the mixing valve which allows you to maximize the potential of your current emitters with low temp water. I spoke with Tom and understand he had a problem spot in the house that he was addressing so that makes sense. To me, if you were going to do 1 or the other (understanding that both is best) I would suggest mixing valve 1st. I replaced my baseboard radiator covers about 5 years ago with something more decorative - I can assure you that if you are doing your whole house $28/ft will add up quickly.

 

[TCaldwell]

Velvet, look on smiths he2, it has 2 elements and can be piped many ways

 

[velvetfoot]

Velvet, look on smiths he2, it has 2 elements and can be piped many ways

I realize, but I just was wondering what you did. My house is probably series on each of two floors. All the piping is under the floor in my setup, and I assumed so was yours. I was wondering if you used the return pipe in some innovative manner instead of just replacing the baseboard.

 

[velvetfoot]

Velvet, look on smiths he2, it has 2 elements and can be piped many ways

I realize, but I just was wondering what you did. My house is probably series on each of two floors. All the piping is under the floor in my setup, and I assumed so was yours. I was wondering if you used the return pipe in some innovative manner instead of just replacing the baseboard.

 

[tom in maine]

Baseboards are convection devices. As such, the taller the housing it, the greater the convection and the higher the heat output.
If you can tolerate a taller housing, you can bump up the output.
Dick Hill and I tested and did this and it works well. Dick had students make stupidly tall housings and the output continued to increase.
The chimney effect is what makes many of the low temp emitters work well.
You could try it somewhere if convenient.
In my own heating system, I am pumping unpressurized tank water with a bronze pump into various radiant walls and floors.
I wanted a bit more output on the first floor of the house and installed a steel radiant panel in the original closed loop system I had.
When I converted to open loop, that panel had to go. I got some fin tube and made a panel with some v match pine as a housing.
It should have a grill on top, but that is still waiting to happen.
It is only 3-4' long but throws out a fair bit of heat.

 

[velvetfoot]

I recall in my last look at this, that there is some commercial fin tube baseboard in tall convectors. I recall they were very expensive and the electric outlets interfered, again, as I recall.

 

[maple1]

Baseboards are convection devices. As such, the taller the housing it, the greater the convection and the higher the heat output.
If you can tolerate a taller housing, you can bump up the output.
Dick Hill and I tested and did this and it works well. Dick had students make stupidly tall housings and the output continued to increase.
The chimney effect is what makes many of the low temp emitters work well.
You could try it somewhere if convenient.
In my own heating system, I am pumping unpressurized tank water with a bronze pump into various radiant walls and floors.
I wanted a bit more output on the first floor of the house and installed a steel radiant panel in the original closed loop system I had.
When I converted to open loop, that panel had to go. I got some fin tube and made a panel with some v match pine as a housing.
It should have a grill on top, but that is still waiting to happen.
It is only 3-4' long but throws out a fair bit of heat.

How high is your v match housing?

 

[TCaldwell]

Velvet, my piping is exposed in the basement

 

[velvetfoot]

Tom, then why did you have to use the return tube inside the convector.

 

[tom in maine]

It's not too tall, only about 8", but that is a bit taller than the housing that is usually used.
I believe you would only count the front panel as the actual convector height. And the top and damper do tend to
cut down the convection on regular baseboards.
If you look around at commercial convectors, they tend to be rather tall. And double radiant panels are really radiators and convectors.
If you can situate them, they do a good job.

 

[Bob Rohr]

It all about the surface area when moving heat. I suppose it depends on what type of look you are after. Panel rads work at low temperature but the required square footage goes up quickly, and the cost

Jaga has some low temperature emitters with small "muffin" fans to force convection. Forcing the air flow really improves output, think of those suspended hydronic heaters seen in shops. The fans have a built in reset control to ramp speeds on the Jaga system.

I've been hunting down unique old cast iron radiators for my shop and office. Running about 125F supply they recover quite nicely and provide radiant and some convection. Here is a corner rad I found up in Omaha I tested, stripped, painted and installed it.

Old cast radiators are available for scrap prices, sometimes free for the hauling.

The infrared is about a 45 minute run from 65 to 125F

 

[cpeltier]

It all about the surface area when moving heat. I suppose it depends on what type of look you are after.

I've been hunting down unique old cast iron radiators for my shop and office. Running about 125F supply they recover quite nicely and provide radiant and some convection. Here is a corner rad I found up in Omaha I tested, stripped, painted and installed it.

Old cast radiators are available for scrap prices, sometimes free for the hauling.

The infrared is about a 45 minute run from 65 to 125F

I've used Governale cast iron baseboard to heat some cold bedrooms using a low temp supply setup for radiant. The water source tops out at 120F and it has worked well.

 

[maple1]

It all about the surface area when moving heat. I suppose it depends on what type of look you are after. Panel rads work at low temperature but the required square footage goes up quickly, and the cost

Jaga has some low temperature emitters with small "muffin" fans to force convection. Forcing the air flow really improves output, think of those suspended hydronic heaters seen in shops. The fans have a built in reset control to ramp speeds on the Jaga system.

I've been hunting down unique old cast iron radiators for my shop and office. Running about 125F supply they recover quite nicely and provide radiant and some convection. Here is a corner rad I found up in Omaha I tested, stripped, painted and installed it.

Old cast radiators are available for scrap prices, sometimes free for the hauling.

The infrared is about a 45 minute run from 65 to 125F

How did you strip it?

 

[TCaldwell]

Velvet, probably best if you google he2 baseboards, it shows 4 different piping options, reverse return, s output was high, along with the benefit of even heat for that length of run

 

[velvetfoot]

Will do. I've done a lot of insulating along the rim joists, where the distribution pipes are, plus there's the second floor, so I'm not sure this elective surgery is in the near future

 

[Bob Rohr]

How did you strip it?

Started with paint stripper, pressure washer, then an assortment of hand and powered wire brushes. It it wasn't so big, heavy, and awkward it would have gone to a sandblaster.

 

[Karl_northwind]

It all about the surface area when moving heat. I suppose it depends on what type of look you are after. Panel rads work at low temperature but the required square footage goes up quickly, and the cost

Jaga has some low temperature emitters with small "muffin" fans to force convection. Forcing the air flow really improves output, think of those suspended hydronic heaters seen in shops. The fans have a built in reset control to ramp speeds on the Jaga system.

I've been hunting down unique old cast iron radiators for my shop and office. Running about 125F supply they recover quite nicely and provide radiant and some convection. Here is a corner rad I found up in Omaha I tested, stripped, painted and installed it.

Old cast radiators are available for scrap prices, sometimes free for the hauling.

The infrared is about a 45 minute run from 65 to 125F

that's a gorgeous goofy radiator.
I'm trying to convince the wife that we can install some old cast iron radiators horizontally as benches in a house we're renovating. she wants to do euro-panel rads, and as I can get them super cheap, that may win out.

my vote for your project Peakbagger, are pensotti panel radiators. I'm going next week to swap out some baseboards for some 12x72" panel radiators. clean, better micro zoning, and a lot more heat per linear foot.

 

[Boardroom]

My house was not conducive to running radiant floor piping so I also fitted my house with old CI rads. I found most of them on classifieds. I think the most I paid for one rad was $100. I got one big one for free just for picking it up. I had a guy with a mobile wet blaster come out to the house and he stripped them all in a day. I just bought spray paint from home depot to paint them. I think in total I bought 13 rads and two leaked when I tested them so I ended up with 11 good ones. My average cost all finished for each one was $180. I have been running pretty hot water through them but JohnDolz has convinced me that cool could work. I guess it will all depend on whether I have them sized properly for the rooms they are in. Getting them clean on the inside is the real trick. I wish I had done a better job with mine.
Here are some before and after pics. Sorry I couldn't get them oriented properly.