Old radiant system with naked baseboard tubing -- how to make safe?

mdboth

Hi folks,

Just bought my first home and it's a duplex. We are hoping to rent out the top floor unit soon and it has a relatively old baseboard style radiant heating system powered by a Takagi tankless hot water heater. There are two issues:

High Priority -- They aren't typical base-board, it's just a pair of naked pipes (one above the other) running around the outside of the room a few inches from the floor and maybe 1/2" to 3/4" from the baseboards -- they get a bit too hot for safety if kids / pets / or furniture end up touching them.
Key Question: How can we most cheaply and effectively make this safe? One recommendation has been to replace them with radiators, however, the main living room is relatively large (20x12 + open air to kitchen which is 12x12 maybe?), and I think this would mean running new piping under the floors to the far side which seems difficult / disruptive / expensive if we removed the above floor tubing that reaches that side today. The only good news here is that the piping emerges at a center point between the living room and kitchen, so it might heat both if it can throw enough heat safely / reasonably.

Another option (which I prefer at this point if cost effective) would be to find a way to retrofit the existing tubing with standard heat diffusing covers like most basedboard heating uses. Is anyone aware of a kit that can turn existing naked tubing into more standard vented baseboard heating? This is the closest thing I've found:
https://heatinghelp.com/industry-news/slantfin/
https://supplyhouse.com/Slant-Fin-104003060-6-ft-Baseline-2000-Baseboard-Cover-Only?gclid=Cj0KCQjw0a7YBRDnARIsAJgsF3PMSDaJ5CiAACtL5RfII0kfNptCpwZ6QduiKTvo7xHm4BxjHTNJ5joaAro2EALw_wcB

but it says that it requires attachement to the existing backing. Is there somewhere I can buy the backing and whatever is needed to attach to it? Right now It's just got some small metal rings holding the piping off the wall.



Medium / Low Priority -- The Takagi still heats water quickly, but it's probably 25 years old and may need to be replaced in the next few years. One of the 4 or 5 pressure gauges mounted near it on the wall is cracked and rusted. Is this baseboard idea a bad one given this situation?

Am I better off going with radiators for some reason? Maybe I can get one large enough that I don't need to run new piping in that room?

Jamie Hall

Is this finned tubing? Or just pipes? If it is just pipes, the next obvious question is -- does it heat the space adequately? (Actually, that apples to both finned or plain...).

As to covers. Yes, you can probably find something which will fit. But, with some competent carpentry, you can create something quite handsome and perfectly functional on the spot. The idea of course is to have a front panel which clears the floor by about an inch and a half at the bottom and then goes up in front of the pipes to about 2 inches above the tops, and then is covered back to the wall with and open grillwork of some kind (there are many variations on that). The air will circulate behind that very nicely and heat the space.

On the heat source. That old Takagi isn't doing you any favours. I would suggest looking into replacing it with a decent modern boiler -- but not of the high efficiency sort, as those pipes, if they are bare (not finned) probably have to run at too high a temperature for the high efficiency boiler to be useful.

JUGHNE

If you have only the 2 bare pipes, it seems that you could have finned tube baseboard installed with the proper covers to replace the naked pipes.
There is room inside that baseboard cabinet to have the return (2nd) pipe installed. In other words they could be connected at one end only or if I understand your case they could be connected in the center without any piping changes under the floor.
The finned tube heaters, with their convector properties because of the housing, would deliver more heat than bare copper pipes. You could possibly lower the supply water temperatures also.

RomanP

I remember swapping out baseboard covers back in the beginning of my Plumbing/heating struggles lol. If you post some pictures, that could help us. As a poster above mentioned, if it doesn’t have fins that can reduce their heat output considerably.

I’d just go after standard Slant/Fin or Sterling or whatever your local supplier carries and would wait for next winter, to see if you get enough heat, using what you have right now....

or.... be proactive...do some heat loss calculations, you can figure out how many btus your copper pipe without fins produces, at the operating temperature of your source. Make your decision based on that

Good luck

EYoder

I would second the idea of making custom baseboard covers. Can boost the convection currents and is a simple fix. Taller equals more output.

Zman

@mdboth
You are going to need to post more info in order get an answer. Posting pictures is easier if you don't understand what is being asked.

mdboth

Wow, thanks everyone for all the tips. I'm taking Zman's advice and posting pictures so that people can get a better sense of what I'm talking about. Without any covers, they seem to heat the place really well. Probably because the water is so hot. Not sure how much covering them up would reduce the experienced heat. Since I'm in northern CA, the temperature never really gets below 40, and pretty rarely below 50.

pictures here:

cdn.net/5021738/uploads/editor/3g/pded2la99eg2.jpg" alt="" />

Jamie Hall

Cute. I thought that was what you were describing. I still like my idea. A gap of about 2 inches from the floor... maybe a little less; low enough to be below the lower pipe. Then go up with a new "baseboard" up to the height of the existing baseboard in back of the pipes. Then cover the top opening with a decorative grille. The new "baseboard" should be about and inch or so in front of the pipes. Doesn't have to be fancy, but I'd use decent lumber and ease the front corners a bit.. It won't cut the heat output much -- most of your heat is convection from those, I expect -- and will look neater and protect them from little poky fingers...

Zman

Well that's not something you see every day.
I think Jamie's carpentry approach would work. It would be a little tricky to be sure as it an untested assembly.
Since all the piping looks to be an out and back arrangement, I think I would shorten the whole thing up and just install baseboard radiators. If you do a room by room heat loss you will know what size baseboards you will need.

EYoder

> @Jamie Hall said:
> Cute. I thought that was what you were describing. I still like my idea. A gap of about 2 inches from the floor... maybe a little less; low enough to be below the lower pipe. Then go up with a new "baseboard" up to the height of the existing baseboard in back of the pipes. Then cover the top opening with a decorative grille. The new "baseboard" should be about and inch or so in front of the pipes. Doesn't have to be fancy, but I'd use decent lumber and ease the front corners a bit.. It won't cut the heat output much -- most of your heat is convection from those, I expect -- and will look neater and protect them from little poky fingers...

I'm guessing it'll heat better with a cover due to stronger chimney effect, especially if you increase the height as much as you can.

RomanP

I wonder what original installer was thinking??? Probably Arby’s lol

hot_rod

It seems restrained like that it would make noise when it heats and cools? Looks like metal to metal hangers?

mdboth

It sounds like there are two main schools of thought in the ideas above:

1. Do the proper heat loss calculations and determine what sort of radiators would be needed to replace the existing tubing
   
2. Build a custom wooden baseboard assembly around the existing pipes
   

Some quick questions regarding #1 above:

1. Sorry for my ignorance, but are there any good resources you can point me to for doing the heat loss calculations, and then the sizing of the radiator based upon it?
   
2. Am I better off hiring a pro for this part? I have no trouble with basic math, and have done similar load calculations for designing solar power generation systems, I assume it's in my means to do so if I can get a proper resource to learn from
   

Questions regarding #2:

1. Building the front wall: How do you recommend attaching the new front baseboard to the house? Hanging it from the back seems structurally inefficient / difficult, but maybe with the proper corner brackets on each side, doable?
   
2. Would it make more sense to just have some supports underneath it connecting to the floor? Concerned about this technique for the two rooms that are carpeted, but probably not a huge deal. If I did this, how far apart would you recommend spacing the supports?
   
3. Where can I purchase a grill for the top, anyone have links to specific products they would recommend, or at least the right terms to search for in order to find my own?
   

Thanks again to everyone, this has been such a huge help!

Very Best,
-Dan

hot_rod

http://www.slantfin.com/products/virtual-heat-loss-calculator/

Easy to use. Once the load is determined, I'd look at installing some of their fin tube baseboard, maybe get rid of quite a bit of that tube. the fins are the key to conduction transfer, not much surface area in that bare tube

EYoder

If you choose to go the baseboard cover route a google image search for baseboard covers brought up some nice wood covers with a gap at the top and bottom for airflow.
Then you'll have something to go by.