Re: Baseboard Heating Problem
Hard to say what to do at this point without being able to look at it; the pipes are more likely frozen than air-bound if they've been working until the latest freeze-up.
If it's just air, you should hear water gurgling thru that pipe section & you should get some air out when you open the bleed valve on the baseboard element.
Are the pipes copper, steel, or PEX plastic????
PEX & copper will expand somewhat without cracking.
If you're lucky that section of baseboard will just stay cold for a day or two until the frozen blockage thaws without cracking the pipe & you're back in business for the time being.
If you have access to the crawl space, you can try bringing in a woman's hair dryer if the pipes are metal and trying to thaw the frozen section----usually at a corner, elbow, etc., & often at the side of the house that gets the prevailing wind---look & feel for any cracks in the wall siding/sheathing inside the crawlspace that is letting in cold air from outside (often blowing directly on the heating pipe)---you will be able to feel it as you brush your hand along the lower siding & sill.
Heating cables are also available in various lengths at the home improvement stores that can be taped to metal pipes to prevent freezing.
Tighten up the crawl space with pink insulation, caulking compound, expandable foam, rigid styrofoam----throw everything at it until there are no more cold drafts coming in; always wear a dust mask when working with loose insulation.
Takle some loose pink blanket insulation into the crawlspace with you & plug up any cold air breezes you detect---the pink blanket stuff is also good for wrapping around the piping that is prone to freeze--there is also black styrofoam pipe insulation in 10' sections available at the home improvement stores.
The heating pipes cannot be left bare in such a crawl space with the freezing climate you're getting; you have to wrap them in insulation, or have an insulation tech blow in some cellulose insulation so the pipes are completely covered.
Another option is to have a few gallons of propylene glycol (non-toxic anti-freeze) (home improvement stores) added to the boiler water---there is a chart on the container that indicates how much to add.
Last edited by Pelton; 12-07-2011 at 12:07 AM.