Adding Low Temp Radiators

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
So what are some reliable brands?
we have and do use Pensotti, with good success. Hydronic alternatives has also been recommended to me by those in the know. on the east coast you will have lots of options. Here in the Midwest, not so much.

karl
 
I was on slant fins app doing a heat loss calc. I know my input was guestimating but the one room of concern came back with a 14,000 BTU @180°F. I currently have 36' of standard baseboard fins. The room is 22 x 15 and 20 ' cathedral ceilings. A fireplace, 75 sqrt of Windows a door that leads to an outside porch and freench doors which lead to my kitchen. This is the coldest room in the house. There has to be a better way than what I have. Outside temp is 44°F.
 

Attachments

  • 1418823901992.jpg
    1418823901992.jpg
    106.8 KB · Views: 168
That's a huge room. Likely presents a heatload similar to a detached 2 car 2 storey garage. You'd likely have to load it right up with baseboard or rads. Can you load the windows with more glass or storms?
 
Pologuy, any chance of underfloor radiant? If you can heat the floor and the furniture, without having to heat the open space, that could help the comfort in that room, and you can use the low temp water still.
 
  • Like
Reactions: maple1
a combination of panel rads and in-floor would work really well in that big tall space. heat the people and their feet with the floor, and the air and crank some real BTUs with the panel rads. you can also use (depending on the water temps) the return water from the panel rad to do some in-floor heat delivery. I have one system working that way and the customer LOVES it. it's in the only(non bathroom)-non carpeted space in the house: the kitchen. His wive is talking about having us com back and do the same thing in the bathroom floor as well. this is a triangle tube 110, with a 38 gal buffer tank and 11 panel rads and a towel bar heater, replacing electric base boards.
 
Heating the floor is doable. My basement is open. I do have nails protruding down from the hardwood flooring. What's the best application for my scenario?
 
Heating the floor is doable. My basement is open. I do have nails protruding down from the hardwood flooring. What's the best application for my scenario?

Been there... done that...

two options..

1. A hammer, bend them all over.

This tends not to work as well as one would expect so then there is option 2...

A ladder or better a Work Platform
a 90° grinder with a cutting disk
an old pair of coveralls (cotton or it melts)
a good face shield, (just safety glasses if you believe that chicks dig scars)
Advil.

be advised, cut nails... cut hard.. DAMHIK...
 
Been there... done that...

two options..

1. A hammer, bend them all over.

This tends not to work as well as one would expect so then there is option 2...

A ladder or better a Work Platform
a 90° grinder with a cutting disk
an old pair of coveralls (cotton or it melts)
a good face shield, (just safety glasses if you believe that chicks dig scars)
Advil.

be advised, cut nails... cut hard.. DAMHIK...


6' Ladder, angle grinder, goggles, baseball type cap, work gloves, work clothes (long sleeves). I did 800 sq feet of them and it was tedious for a few evenings but not hard.
Four year old child to hear the noise, run down stairs, observe for a minute with a gaping mouth, and run back up to ask "Mama, why is Dad shooting sparks across the basement?"


ALSO, EARPLUGS!!!
 
Last edited:
  • Like
Reactions: CaptainK
Send me some pictures.
Had a chance to take one of the radiator in the girls' bedroom.

Added one of the small rad in the bathroom (someday I'll finish the trim and cover plates).
Also added a couple of the retrofit underfloor. In one of the pictures you can see the Thermofin panel angled to go around the soil pipe.

ETA, this was Buderus brand, but it looks awefully similar, including model number and size to the fraction of an inch of the one that you posted. I'm not sure who manufactured it, but I think this panel is sold under several different brand names.
 

Attachments

  • 100_4555.JPG
    100_4555.JPG
    132.4 KB · Views: 196
  • 100_4556.JPG
    100_4556.JPG
    218.7 KB · Views: 184
  • 100_4557.JPG
    100_4557.JPG
    195.1 KB · Views: 192
  • 100_4558.JPG
    100_4558.JPG
    127.8 KB · Views: 196
Last edited:
Heating the floor is doable. My basement is open. I do have nails protruding down from the hardwood flooring. What's the best application for my scenario?


The best tool that I found was an air powered die grinder with a thin muffler cutting wheel. It's much faster spinning compared to an angle grinder and takes less metal per cut.
You can get real close to the floor and the tool never gets hot to hold.

There are electric versions also. Thin wheel, high rpm gets the job done quickly. Also a hat for the sparks and a fire extinguisher near by.
 
  • Like
Reactions: GS7
What do you think about me switching the 20'+ section with 20feet of panel rads with the 22 series. It would bump me up to 20,510btus. Then I could add the trench system for the other 10 foot section of baseboard. Eliminate the remaining baseboard.

Any thoughts or suggestions.
 
I'm going to be watching this as I have been thinking the same thing for one of my rooms.

You and me too...Has anyone with forced air added low temp radiators to their system? I'm thinking the return line of the water to to air heat exchanger could be tapped into.
 
I have a lot of cast iron radiators. Thats all they used here at one time years ago. Can still be purchase new for about $100 a foot.
 
Appears to be more prevalent than I thought. I thought I was somewhat alone in this. These systems are phenomenal. Imagine dialing everything in with the right equipment.
 
After researching this further, it appears there are two major players in Europe. Quinn and Rettig. Myson, hydronic alt, pensotti, dianorm, purloined appear to be one of the two. If you look at the specs they're all pretty much the same. So I'm looking for bang for the buck. Runtal seems expensive in comparison.

I think over sizing it it the way to go. If I'm able to plumb this to receive the return water from my other zones, that could be an added benefit. Haven't figured out the how yet. It looks as though going to a much larger configuration gives the room heat at higher temps as well as continued heating at lower temps. I could always add trenching or radiant if this isn't sufficient. Most Europeans with gassers use radiators.
 
After researching this further, it appears there are two major players in Europe. Quinn and Rettig. Myson, hydronic alt, pensotti, dianorm, purloined appear to be one of the two. If you look at the specs they're all pretty much the same. So I'm looking for bang for the buck. Runtal seems expensive in comparison.

I think over sizing it it the way to go. If I'm able to plumb this to receive the return water from my other zones, that could be an added benefit. Haven't figured out the how yet. It looks as though going to a much larger configuration gives the room heat at higher temps as well as continued heating at lower temps. I could always add trenching or radiant if this isn't sufficient. Most Europeans with gassers use radiators.


Here is a cheat sheet to show output change at different temperatures. From Caleffi idronics 6, google that if you need more info. Built around the Dianorm but they are all very similar in construction and output tables. Easily found in the US Dianorm, Pensotti, Buderus, Rental, Myson. Steer clear of imports from PRC

Probably hundreds of panel rad manufacturers in Europe from mild to wild. I'd guess 80% of the heating in Europe is panel rads, most think it is radiant floors. Even the centuries old castles you visit have panel rads retro fitted into them.
 

Attachments

  • Screen Shot 2015-01-03 at 9.45.51 PM.png
    Screen Shot 2015-01-03 at 9.45.51 PM.png
    51.9 KB · Views: 205
  • Screen Shot 2015-01-03 at 9.46.03 PM.png
    Screen Shot 2015-01-03 at 9.46.03 PM.png
    41.6 KB · Views: 210
Thanks. So figuring I want have consistent water flow @ 180 but rather 160s the btu drop off. So over sizing would probably yield the consistent 70° heat in the room.
 
Thanks. So figuring I want have consistent water flow @ 180 but rather 160s the btu drop off. So over sizing would probably yield the consistent 70° heat in the room.

Ideally you would have an outdoor reset so the water temps rise and lower with the outdoor temp.
 
With this weather in the mid 30's I've been running my storage down to under 100 degrees !! I just time my fires to when I will be needing DHW, because at 120 and lower I wouldn't have much DHW.
 
Thanks. So figuring I want have consistent water flow @ 180 but rather 160s the btu drop off. So over sizing would probably yield the consistent 70° heat in the room.


Correct, keep in mind that graph is used with average water temperature, not the supply. So if you are supplying 160 with a 20° temperature drop you have an average of 150.

Using that graph above 150- 70 air temperature = 80. Run up to a .65 multiplier. Take the radiator out put from the sheet times .65 and see what the output will be at reduced temperature.

Remember also if you put multiple radiators in series, you have a temperature drop at every one, the last in line seeing much lower temperature. Generally 2 maybe 3 small rads in series.

It's all about the surface area, which is why radiant floors or ceilings running 90 temperatures need to cover the entire square footage of the room.

The plus with panel rads is the output is radiant and convection, so they do move some heat via air currents.
 
This was with my tanks starting out at 111°. Flue temps were consistent. This zone is the shortest. It's right above the boiler room. I'll do the panel rads and eventually pipe in some underfloor radiant as well. I measured again. I have a 22', 10' and 4' section of conventional baseboard. Replace the 22' with 20' of panel rads. Get rid of the 4' and replace the 10' with another 10'. That increases the btu output to 32,700 btus@ 180° then downward based on your previous calc. The water is being pushed by a big pump, taco 2400-20.
 

Attachments

  • IMAG0931.jpg
    IMAG0931.jpg
    86.6 KB · Views: 130
  • IMAG0932.jpg
    IMAG0932.jpg
    90.2 KB · Views: 143
I have four zones and adding a fifth. I was running a 007 which I was told was insufficient if multiple zones were calling for heat. I thought of a variable speed but decided to add a third 2400-20. My thought was to have the velocity just in case all zones were calling. I thought the quicker the water flows the more consistent the temp would be. If the water dragged through the run it would cool quicker. Going through quicker would decrease the heat lose.
 
I'm back........after calling around and looking at the numbers, I'm sizing the panel rads at 150° supply. This will give me a consistent 67° heat and possibly higher when the supply is 170°. Now my major concern............which unit to buy. I've contacted a few places and so far hydronicalternatives has given a decent price. If anyone has used panel rads in their setups, please give the brand you used. I would GREATLY appreciate it. I want to drain down my system next week. It would be perfect to add the panels then.

Thanks again
 
Status
Not open for further replies.