Radiant Pipe Embedded in Concrete Leaking, Heat Lacking in Some Areas

Alex_19

Hey,



I am posting this regarding my aunt's home. I can request from her any information you may need to best assist.



My aunt's home was built in the 1950s, is approximately 2,500 sq ft. and most of it is poured concrete. In many areas, the concrete floors and walls are about 12 inches thick. The main level is heated, and there are radiant lines running up to an unfinished and unheated attic. Her family seems to remember that the house, which was custom-built, has the radiant lines embedded within the concrete.



Over the past five to ten years, some areas on the main level have reduced heat or lost it entirely. Only one room, above the furnace, gets very hot. The kitchen, which is furthest from the furnace, is the coolest. All the other rooms have very little to moderate heat.



Two weeks ago, she discovered a leak at the side of the house near the kitchen which really starts flowing when the furnace is running. Over the years, there have been other leaks, but at present, she is unaware of any additional active leaks.



The furnace is in the unheated unfinished basement, is gas-fired with a circulating pump without a tankless coil. It is approximately 20 years old. During the last heating season, she found that she had to add water to it every 1 to 2 days, which was considerably more than she had to in prior years. She also insists she has to oil it regularly. She doesn't observe any localized leaks at the heating plant. Excessively high gas bills have been generated during the heating seasons over the past few years.



The question I would please appreciate guidance on is: Under these circumstances, what is the best way to assess where any additional leaks are and how would these be repaired?

kcopp

you need to....

open up the floor... If that is not practical then at least isolate that loop if you can. I did this for a system a number of years back at it worked well for a bout 2 more years. Unfortunately unless you are willing to do a bunch of repairs, you are on borrowed time before abandoning the system and going w/ a new set up.

I ended up having to switch the system out to hot water baseboard.

Jean-David Beyer

switch the system out to hot water baseboard

My house is about 60 years old with copper tubing in concrete slab on grade.

As far as I can tell, it does not leak. I can turn off the makeup water for over a month and the pressure does not go down. Pressure gauge seems to work OK..



If (when?) that starts to leak, I do not propose to put in baseboard, though someone (not here) recommended I do that. I think I will go for a radiant ceiling instead.

Zman

IR camera

An IR camera is going to be your first troubleshooting tool. I think you need to figure out how bad it is. If you have one leak it may be worth attacking. Many leaks would have me looking for "Plan B".

Carl

Alex_19

RE: IR camera

Thank you for the replies so far! What kind of IR camera is good to use and where can they be rented/purchased?

Zman

Energy Auditors

I would start out by looking for a local energy auditor. We have a local non-profit auditor that rents them.

McMaster

thermo cam

It is probably a good suggestion to see if you can find a local utility energy advisor who has one you can use. To buy one, you're looking at about $3,500 on up. Renting one is usually about $100/day.

Did you say the floors can be 12" thick concrete? The edge of the foundation might be 12" thick, but it's hard to believe the floor would anywhere near that thick, just because of the cost to install a floor like that, let alone the heat transfer (or lack of) with a slab that thick. It's probably more like 4" thick. If it IS 12" thick, you're going to have a problem getting at the pipes. If it's just 4", then you can get in there with a demo hammer and repair the bad areas. 

If it's old and you are experiencing a LOT of leaks, then maybe it's time to think about baseboard heat, or redo the floor heat. Two approaches to take here: One is to lay down some new PEX radiant tubing and pour 2" of concrete, gypcrete or some substance. Or, have a demo team come in and they could probably have the floor removed in about a day, then have another contractor come in and redo the heating in a new floor. 

Jean-David Beyer

If it's old and you are experiencing a LOT of leaks,

[I see I said this before.]

I have pretty much decided to put in a radiant ceiling if that happens.