Home>Discussions>INSULATION & HVAC>How do you remove radiators for repair?
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Handy Gal
How do you remove radiators for repair?

I want to pull out several hot water radiators throughout the home i just purchased to do some work on the walls and floors, not to mention repaint the radiators and flush them.

I'm having a hard time finding out any info on how to do this and was hoping i could get some information or tips from someone that has done this before.

I have 4 weeks to complete the home before i need to start moving in. Am i biting off more then i can chew? :confused:

Re: How do you remove radiators for repair?

depending on type of radiator. Steam Radiator or Hot Water radiator. [ one pipe / two pipes..etc]
shut off steam or water supply to radiator.
disconnect all pipes connect to radiator.
remove radiator.
..Caution...Most of them are cast iron radiator and they are frickin heavy. If you cannot do it yourself then please get couple strong guys to move them.

FYI...Be very careful on pipes. They can break off easily.

Re: How do you remove radiators for repair?

possibly. however, that is how you learn. you will need to shut off your boiler or heating source and then drain the sytem at the lowest point. then go the the highest point and crakc open the unions on the radiator. there should be a union fitting on both the inlet and outlet (supply and return) pipes of the radiator. use your large sized adjustable wrench and another for backup. loosen the union and be ready for the water.

this is why alot of walls behind toilets and radiators never get that touch paint.

Re: How do you remove radiators for repair?


As noted, actually removing the rads can create additional problems of draining the system of water, great weight involved, possibility of leaks when reinstalled, recharging the system with water, removing all air from the newly-charged system.

Often, it is more expedient to strip & re-paint the rads in place--the space behind the wall can usually be reached & repainted if the rad is covered with plastic sheeting, or even a plastic garbage bag.

I would recommend doing the best you can to refurbish with the rads in place.

Caution: some rads have been painted with lead paint, which can be a breathing hazard if you strip the old paint---wear a dust mask designed for paint particles.

Using a steel wire wheel attached to a drill can usually do the trick---don't ignore auto supply & auto body stores in your area which carry paint stripping drill attachments made by 3M & others for effective, fast paint-stripping.

Cast iron rads are considered one of the BEST ways to heat a room---do everything you can to keep them--you won't be sorry when the winter comes & you feel the great heat they produce---there is usually no need to "drain" the rads---they rarely get blocked up---poor heat performance is usually caused by air in the rad or poor flow problems in the piping--rarely problems with the rad itself.

Handy Gal
Re: How do you remove radiators for repair?

Thanks for the reply's...

Actually it has become essential for me to now remove the radiators in my new home or at least one (thou they are not zoned). During cleaning we found the "wet" plaster walls had paint chipping off behind the radiators and down to the original bare plaster. So there is a lead paint issue we need to address prior to moving my 18 month old son into that room.

Is it common to find plaster/paint issues behind old radiators?

The radiators are hot water with air bleeds at the top junction and a shut off near the intake at the bottom.

I am guessing the the lowest point to drain them would be in the basement. And what would i look for down there? Some sort of drain valve? I'm sure I'm not gonna find a handy hose hook up, that would be too convenient for a system that is 25+ years old.

And I am... we are prepared for the weight as I have recruited assistance to move them when that time comes.

Re: How do you remove radiators for repair?

Handy Gal:

I think if you follow the steps outlined by Big Walt & misfitter you will be able to remove the rads.

1) The initial step is to TURN OFF THE ELEC. SWITCH on the boiler (or at the top of the stairs)---also turn off the WATER INLET VALVE that allows fresh water into the boiler piping system--this valve is located usually at the top somewhere near the boiler.

2) check the temp/altitude (psi) gauge on the boiler & take a 5 gallon bucket & remove a gallon or two from the boiler drain located at the bottom of the boiler---the boiler drain looks like a regular outside brass faucet with a standard handle.

3) the altitude needle on the psi gauge should drop from 12 psi to 0 psi when the water is removed--you should hear no water refilling the system if you turned off the water supply valve.

4) go up to the radiator you intend to remove first (should be located at the highest point) & open the little bleed valve at the top of the rad to let in some air so the water will drain out of the system (you should hear a sucking sound of the water going down to a lower level in the piping)--go round & open the other rad bleed valves to the rads you intend to service to let air into the system to ease draining.

5) as noted, take a large plumbing wrench & loosen the large nut that connects the supply & return lines to the rad---if a lot of water still comes out when you loosen with the wrench, retighten & go down to the cellar & drain another gallon from the boiler drain valve.

6) once the large nuts are loosened, the supply/return piping should be able to be moved slightly so that you can pull one side of the rad away from the wall---the rad will be heavy & there is usually a lot of black, gooey inky iron oxide liquid at the bottom---block the two bottom holes of the rad with a wad of paper toweling to prevent this from getting all over the floor until you have the rad away from the wall.

7) once the rad is away from the wall, place a large pie pan/cake pan, or similar low-edged drain pan under one end of the rad---use a 2 X 4 stud as a fulcrum/pry bar to lift one end of the rad to drain the black goo into the drain pan---just a slight lift with the 2 X 4 is needed---be careful you don't allow the rad to fall on your foot or leg.

8) do your cleaning, stripping, repainting of the rad & wall surface & replace the rad---it is efficient to put a large piece of reflective aluminum or steel against the wall behind each rad to reflect the heat out so it is not wasted & prevents future wall paint peeling.

9) When all the rads are done & tightened back in place, go back down to the cellar & re-open the feed water valve to the boiler piping to allow fresh water to fill the system---check for any leaks near the rads & tighten the connections if you see any.

10) keep all but one of the rad bleed valves closed until the water arrives & starts to come out of the bleed valve----you can then close that valve & go to the next rad & open the bleed valve & bleed the air out of each successive rad that has been serviced until you see water come out.

11) turn the boiler switch back on at the boiler to return the boiler to service.

12) turn the heat up to fire the boiler to drive the air out of the new water (new water introduced into the piping has a lot of entrained air in it)---turn the heat off & again go around to every rad bleed valve & bleed any air that has been forced out of the new boiler water.

Handy Gal
Re: How do you remove radiators for repair?


This sounds like the best step by step info i could get.
I'll be sure to try this when we get to that point and I will post how well it goes. ;)

Thanks for the feed back.

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