QUESTION FROM Larry

What to do after a frozen pipe bursts on a hot water oil burner baseboard?

ANSWER FROM HOME-WIZARD

Dear Larry:

I'm very sorry to hear that you had a frozen water pipe burst in your hot water baseboard heating system. Hopefully you did not incur much water damage, which can be a real mess and the damage can be extensive.

Regarding your question of what to do after a frozen baseboard heating system pipe bursts, here are a couple of thoughts:

1) Obviously, shut off the water supply to your baseboard heating system immediately.

2) Do NOT try to heat your pipes to thaw them out with anything stronger than an electric hair dryer. Using a stronger heat source (such as a torch or propane heater) can cause the trapped water to boil and explode.

3) Unfortunately, you might find that when your baseboard heating pipe froze up, that in addition to the section of line where most of the water came out, that there may be other sections that were also damaged, and will therefore also need to be replaced. This is because when one one section of baseboard pipes freeze, it can also freeze upstream and downstream of this section of the pipe (including inside the walls). And further, unfortunately you should also check your toilets and their traps, to see if they show any cracking from the same low-temperature incident that caused your baseboard heating pipe to burst.

Hope this is helpful.
Home-Wizard.com

QUESTION FROM momothemonstor

Our lakehouse uses water baseboard heating. We recently had a pipe burst which resulted in alot of water damage. We were wondering, what would happen if we turned off the valve from the main water supply? (So that if it every burst again, we would only have a leak equal to the amount of water in the system). Would we then be introducing air in the system? (as I understand it the system normally may lose water due to small leaks and it automatically compensates for this by adding new water - but if no new water is available, then I figured I'd have air in the system.) Thanks for your help!

ANSWER FROM HOME-WIZARD

Momothemonster:

Sorry to hear about your burst pipe in your hot water baseboard heating system at your lakehouse.

I assume that since you say your pipe “burst”, that your lakehouse is a region of the country where it gets below freezing (when water freezes, it expands, and the force of this expansion is so powerful, that it can cause even steel pipes to rupture).

To answer you question, yes, you can shut off the main water supply valve, BUT you will also need to DRAIN your water system completely (BOTH hot and cold). If you don’t completely drain the water our of all of your pipes, then the trapped water in the pipes can freeze and burst one of your pipes, and then when you turn your main water supply valve back on you will have a mess on your hands.

And then in the Spring when you turn your main water supply back on, you will need to bleed the air out of your hot water system. For a description of how to do this, you can go to Home-Wizard’s online Maintenance Library, to the page on “Baseboard Heating System Maintenance”: http://www.home-wizard.com/maintenance/baseboardheating.asp

Hope this is helpful.
Home-Wizard.com

FOLLOW-UP FROM momothemonstor

Thank you for your response! And you assumed correctly about living in a cold region. We think we must have lost power and therefore the water was no longer being heated (as it is powered by electric) and therefore froze.

But just to clarify on your comments.....if I wanted to keep the heat on (at a low setting), I should keep the main water supply valve ON? (Otherwise my other choice is to do as you suggested and turn off the water (and have no heat) and drain the pipes.)

Thank you!

ANSWER FROM HOME-WIZARD

momothemonster:

You have some good follow-up questions.

Yes, it sounds like you lose power from time to time, and then get freezing in your baseboard water heating pipes. And since it sounds like you have electric water heating, you not only lose the water being heated, but you also lose the electricity for running the water circulation pump for your baseboard water system. In other words, even if you switch to oil or gas for your boiler, when you lose electricity, you still would not have power to circulate water through your baseboard water system, and therefore your pipes could still freeze and burst.

And yes, if you want to leave the heat on, you can still shut off the main water valve.

The risk, however, is that if you lose power for long enough period, you could still get freezing in your baseboard heating pipes (plus freezing in your toilets, household water pipes, sink drains, etc.) and get damage from the frozen water expanding. But you will have limited how much water spills out by closing the main supply valve.

If you do decide to turn your heat off, remember that you not only need to drain your baseboard water heating system, but also your water heater tank, the household water system, etc. And if you cannot drain water completely out the traps in your sinks and toilet bowls and tanks, then you will need to put a small amount of RV antifreeze in them. And you should also leave open all faucets and showerheads. And if you have a refrigerator, it should be cleaned out, unplugged, and left with the door propped open.

If you have any questions about how to completely drain the water out of the equipment and plumbing for your particular lakehouse (since this can be rather tricky), then I suggest that you should consider using a trained professional who can come out and do the appropriate service.

Hope this is helpful.
Home-Wizard.com

QUESTION FROM Michelle

I have a baseboard heating system in my apartment. While I was out of town, I was informed by my landlord that the pipe froze and burst. One window was barely open. My apartment is always very warm and as a result I have never needed to put on the heat, and always have a window slightly open. The window was open for 4 months of winter without incident and my apartment remained warm. I noticed after the repairs, some sort of valve was replace approx 5 feet down the pipe from where the pipe burst. I have never seen the burst pipe and I was wondering if there could be any other reason for the pipe bursting.

ANSWER FROM HOME-WIZARD

Dear Michelle:

Was the pipe that burst in an outside wall or behind a cabinet that was on an outside wall?

If so, these are areas that can get much colder than other parts of your apartment. Especially behind cabinets where they can be very little air circulation.

Home-Wizard.com