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Hot water baseboard leaks.

BillButtrillBillButtrill Member Posts: 8
I would love to hear how you test for leaks in a hot water baseboard system. I have a system which has suffered major freeze damage. Using water to test for leaks only adds to the damage. Air is ineffective because of the vast number of breaks. Not sure that I want to use smoke in the house for a number of reasons. (smoke detectors, residue, etc.) Any suggestions??

Thank you in advance for your time, Bill


  • GordyGordy Member Posts: 9,523
    Either fix whats visibly obvious, and test with air to see what else is left behind. OR do a total ReCon.
  • hot_rodhot_rod Member Posts: 13,837
    Define a vast number:) might be time for a complete repipe. Frozen pipes will not only great split lines but also push off soldered fittings. You could be doing repairs for a long time and one leak, down the road could ruin your day, or home.

    Pex or PAP goes in quick for a redo.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • SWEISWEI Member Posts: 7,356
    We test first using high pressure air (typically 2X the expected operating pressure, but always at least 10# higher than the PRV rating.) If it holds this for 24 hours, we move on. Once the boilers are up and running and the obvious air is purged from the system, we monitor the system pressure for at least four weeks -- expecting to add a bit of water every so often but eventually we should see at least two weeks with zero drop in pressure.
  • icesailoricesailor Member Posts: 7,265
    Sounds like you had a serious freeze up. Was this a bank foreclosure where the owner walked away and the bank didn't do any "due diligence" in protecting their property? So, you bought it "As is". You get to cover the bank's negligent loss. Lucky you.

    If it is as bad as it sounds, you have to break up the spaces into sections and fix it that way. If you have a lot of split baseboard sections, its almost worth just replacing them all because leaks in the push nipples between the sections often weep after everything looks fixed.

    If the building is located in a place where once it got cold, and it stayed cold, the damage can be really bad. If on the other hand, it is in a place where there are a lot of freeze/thaw cycles, it won't be as bad because the pipes break during the freeze and drain during the thaw. So sometimes, things get saved.

    If there is a really large amount of broken cast iron baseboard, you might want to consider replacing it with copper baseboard. Just be sure that you buy decent baseboard that will cover where the old baseboard was. Cut it to fit to length to save on carpenter work. The copper baseboard, if you buy the better baseboard, will have a higher output than the Cast Iron.

    If you don't own a small portable air compressor, buy one. Don't look for leaks with water. It is far easier to find and clean up after an air leak than with a water leak in a broken pipe. You can test for leaks at 10#. You can hear air leaking at 5#. You're just using the air to locate leaks.
  • BillButtrillBillButtrill Member Posts: 8
    Thank you for your suggestions. Perhaps I did not identify myself sufficiently: I am a Master Plumber. 38 years in the trade. The "how to fix" is not the problem. "Locating" is the problem. And, as stated in the original post, air is not effective. Too many breaks to build up any pressure to be able to hear the escaping air. Dealing with copper fin tube, NOT cast iron.
    Thanks again, Bill
  • BillButtrillBillButtrill Member Posts: 8
    I agree Hot Rod, but sometimes you just can't convince the customer in the wisdom of a re-pipe. "I can't afford that." Maybe not today but it might cost you twice tomorrow. Penny wise and pound foolish.
  • BillButtrillBillButtrill Member Posts: 8
    Gordy, that is exactly where I am on this project. I was just reaching out to see if perhaps there was another tool on the market that I was not aware of. As mentioned earlier, I am a little "long in the tooth" and wanted to make sure that I was up-to-date on my arsenal of Knowledge and Equipment. It looks like air is my only choice. Thanks everyone.
  • GordyGordy Member Posts: 9,523
    edited October 2014
    Ya mean you never bought a magic wand off eBay?? Tough scenario your in.
  • icesailoricesailor Member Posts: 7,265

    Thank you for your suggestions. Perhaps I did not identify myself sufficiently: I am a Master Plumber. 38 years in the trade. The "how to fix" is not the problem. "Locating" is the problem. And, as stated in the original post, air is not effective. Too many breaks to build up any pressure to be able to hear the escaping air. Dealing with copper fin tube, NOT cast iron.
    Thanks again, Bill

    We're in the same boat, rowing upstream in the same shipped river.

    No matter how many leaks or how large they are. I still always used air. Don't worry if it doesn't hold pressure. If it does, there's no leaks. If it is copper baseboard, the leaks are almost at one end or the other, after the first fitting or coupling.

    Use a small air compressor like for a nail gun. I always used oil less under $200 compressors with 3 gallon hot dog tanks. Set the regulator to 25# and open the air feed slowly and let air flow slowly in. You can walk around and find the leaks. If there's a leak in a wall, you can hear it and cut a hole where appropriate.

    I became so dependent on my air compressor that it became a permanent tool in my truck. I've re[aired hundreds and hundreds of broken frozen pipes.

    Fortunate for you the baseboard is not Cast Iron. That is a job I wouldn't look forward to. Renewing my friendship with baseboard squeezers and 3/4" Push Nipples.

  • BillButtrillBillButtrill Member Posts: 8
    Yup, that is where I am. And, "Yes", one of those small compressors is standard equipment on my truck. That size is portable so it can go on any job. Great for winterizing, etc.
  • BillButtrillBillButtrill Member Posts: 8
    To Ice Sailor: I can't go along with, "the leaks are almost at one end or the other, after the first fitting or coupling. " The operative word being "almost." My experience has been that there are multiple breaks on the same length of baseboard. More than 4 on an 8' length and I just replace the whole piece. It is not cost effective - for me OR the homeowner - to make that many repairs on that short of a run. But, thank you for taking an interest in my problem.
  • Eric_32Eric_32 Member Posts: 264
    I just did one this past summer. Probably 8 to 10 breaks on the water lines. Was not able to budge the gauge off zero. Having the compressor outside away like even in the truck with the doors closed helps. Couple of breaks I had to cut open the sheetrock ceiling to find. As I fixed the visible ones, the hidden ones were louder to find.

    If you can't find them using your compressor you need more air. Bigger compressor... like tow behind 80CFM or plus. So you can hear the leaks. More power to push more air so you can hear it, I guarantee they won't elude you with more air.

    Sheetrock is cheap the plumber is expensive.

  • icesailoricesailor Member Posts: 7,265
    I never said that I wouldn't replace a whole section of fin tube. Just that in houses that freeze up and are found still frozen or thawed, there are usually breaks where the fin tube connects with the regular tubing. The copper used for the fin tube has the thickness of quality tree stand paper. Type M Copper is much thicker. The split is AFTER the connection.
  • icesailoricesailor Member Posts: 7,265

    I have extremely sensitive high pitch hearing. So much so that if my wife gets in the car with a bottle of soda and the cap is loose, I can hear the bottle bubbling and I have to tighten the cap.

    To me, absolute silence is the noisiest environment I can be in. Silence makes every noise amplified. If it is absolutely silent, the only noise I hear is a slow leak. I've been at the supply house and walked by someone's truck that had a nail in the tire. No one else heard it but me. I could never work alone unless I had a radio or some familiar sound source. The silence was upsetting. I needed something to cover the sound of silence. I preferred to work alone because on some jobs, the sounds of crews, tuned the multiple radio stations at the same time just sent me over the edge. There was a contractor I used to work for that would allow only ONE radio on a job. And if you didn't like HIS music, you could leave. Once, some yokel insisted on playing his radio with the contractors radio, and the contractor yanked out the plug and chopped off the end. That got his attention.
  • IronmanIronman Member Posts: 5,802
    After you've fixed the obvious leaks, you could add small, controlled amounts of water using on of these:

    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • icesailoricesailor Member Posts: 7,265
    I have an old (60+year) brass bilge pump that I use to pump out toilets. It doesn't use cup leathers. but a cast brass piece on the bottom to provide the vacuum or pressure. I can push it to 150# if I want.

    I always carried a air tank (like for filling car tires) to use to blow up test plugs. One day I decided that it was silly to fill my air tank at home when I could carry the compressor which was actually easier to carry than the air tank. Then, one day, I decided to blow some air out of something I had to fix. No water run back. Then, I realized that it was easier to carry my air compressor into a basement to drain the building than carry a handy pump. It still needed electricity. A 50 to 80 gallon electric water heater will blow out/drain in well under 10 minutes. In the winter time, the air compressor never froze and broke because I didn't get all the water out of it. One day. I realized that I hadn't used my electric water pump in so long that the impellor rusted in place. The air compressor still works.

    When I moved to Florida, an air compressor was one thing I made sure to have room in the truck for.

    You can blow out a building with compressed air so it will not freeze and break. But you can't pump the water out of the same building and not have it break from left over water.

    At least that was my experience.
  • BillButtrillBillButtrill Member Posts: 8
    Thank you all for all of the comments and suggestions. Wish I had Eric's problem: I am deaf as a post. I also had a similar experience w/a radio on a job site. I was a young apprentice and some yahoo was playing his radio loud enough for him to hear it on the third floor. Repeated (polite) requests to turn it down fell on deaf ears (Pun intended). So I cut the plug. It was a union job and they shut it down; I was doing "electrical work" without a license. Go Figure. My boss was not happy w/me - in public. Later he told me that he was fed up w/that radio also. LMAO. Again, thank you all for your prompt responses. Air is the only way to go apparently. I will now consider this post closed. Bill
  • WeezboWeezbo Member Posts: 6,232
    edited January 2015
    Hello ,
    I say it depends... With or without ice in the lines for one.
    while air is possibly most plumbers choice , i like ultra sound. Sometimes. The instrument is a lot lighter than a compressor, checks leaks to .06 thousandths of a psi per year (Bubble tight) rather than 100 psi for 15 mins.. and basically gives a visual read out as well as a sound that may be amplified or reduced as you near a leak.
    Go Pro makes this tool . You may like to get one, as it can save many hours if not days ...finding leaks in large buildings.

    Hope this was helpful.

    *~/: )
  • WeezboWeezbo Member Posts: 6,232
    Yay ! I won something ! LOL Cool! Thanks Dan and community.
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