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radiator that doesn't work after being moved

In our 80+ year old house, we recently had our bathroom renovated. To accomodate a larger vanity, we had the radiator moved down the (same) wall about 2 feet from where it originially was. Now that the bathroom is finished, the radiator will not heat up. All of the other radiators in the house will get toasty warm, but this radiator will no longer heat up. We have bled all of the radiators, including the bathroom one, 3 or more times since the radiator was moved and nothing but water comes out of the bathroom radiator - no air. But it still won't heat up. I should say that, twice, for short periods of time, it has gotten slightly warm, but only twice. We check it every day when we walk in there and it stays cold. Our contractor doesn't seem to know what the problem could be. What could be the problem?

Re: radiator that doesn't work after being moved

Could be any one of 5 possibilities.

These are usually classified as "flow problems", where the heated water in the main pipe is seeking the least path of resistance back to the boiler, because it sees the bathroom rad for some reason as offering too much resistance for it to flow through.

First try to determine what type of supply piping you have going to the dead rad---it should be the same as all the other rads---check the site below & click onto "loop hot water piping (series piping" and "diverter-tee (monoflo tee) piping", "2-pipe system piping", etc. to see which one is closest to yours---also read the several following pages on how water behaves in heating system pipes---always following the LEAST PATH OF RESISTANCE as it flows thru the piping---much like heavy traffic seeks the least crowded road in rush hour.

It's probably not series piping, otherwise you would get SOME heat in the dead rad---oftentimes the bathroom rad is the last in the line of rads to be heated before the cooled water in the main returns back to the boiler.

1) if it's a monoflo system, the monoflo valve may have been installed backwards--this would be in the cellar, where the bathroom hot water supply branches off the main pipe to the bathroom rad.

2) there may be an air pocket in the nearby piping created by the renovation.

3) there may be a slight crack between sections that is preventing water from flowing thru the rad.

4) there may be some crud buildup in the supply pipe or the return pipe of the bathroom rad that is creating a resistance to easy water flow, so the hot water is bypassing the rad.

5) the piping leading to or exiting from the bathroom rad has too many loops in it that causes excessive resistance to water flow.

If you want to attempt a repair yourself, shut down the boiler (on-off switch) & shut off the cold water intake supply valve to the boiler to prevent water from entering the piping system.

Open the bathroom rad bleed valve & drain as much water as will come out of the valve---then remove the bleed valve altogether---take an automobile tire air fill stem (auto supply store), attach it to a bicycle pump, jamb the auto stem into the bleed valve hole & pump 10 strokes of air into the rad---DO NOT USE A COMPRESSOR FOR THIS PROCEDURE.

This is often enough to loosen any restrictions that may be in the piping.

Replace the rad bleed valve, turn the cold water supply back on at the boiler & bleed the bathroom rad of all air---switch the boiler back on & see if there is a change.

It may be necessary to repeat this process again, & also use a 3-5 gallon bucket to drain a gallon or two out of the bleed valve to flush out the nearby piping.


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