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Moving a Radiator.

I have a two-pipe hot water heating system.

I want to move a cast iron rad. It is about 3 ft wide and 3 ft tall. Both the inlet and the outlet to the rad are on the same side of the rad, side by side, towards the bottom of the rad. Is it ok to switch the inlet and the outlet? In its new location, it will be easier to pipe the rad with its old inlet as the new outlet.

My other question is about the valve which is an angle valve screwed on to the 1 1/4 in supply pipe coming up thru the floor. I would like to take it apart before heating it up with a torch to unscrew it to prevent burning up rubber parts inside the valve. The packing nut looks like it will come off easily but there is no obvious way to remove the stem of the valve. Perhaps the thick coats of paint on the valve body is making it hard to see how to disassemble the valve. Thanks in advance for your help.

Re: Moving a Radiator.

Offhand I would say it's ok to do it.

Since the hot water is pumped, the inlet/outlet shouldn't matter.

I've never heard of a cast iron rad that has that type of configuration---any photos you can post would be appreciated.

The new location should be along an outside wall, preferably under a window so the rad would offset the cold air and improve air circulation.

Re: Moving a Radiator.

Thanks, NashuaTech, for your help. I finished moving the rad, it wasn't too difficult except for lining up the pipes to the rad. The ceiling below was finished, so I had no access from below.

Here is a picture of the rad before I moved it.

I used 3/4 in copper pipe and had to heat it to bend it slightly so I could line up the pipes.

Re: Moving a Radiator.


Good job & congrats on a successful install--it does my heart good to see someone get it done & save some $$$--I'm sure you learned a lot about hw heat in the process.

Nice looking rad--they're reputed to be one of the best heating systems in existence--looks like you solved the valve problem as well.

Being able to shut down the system & make a repair such as this will stand you in good stead in mastering your heating system.

My calc for heat output for this rad, assigning 170 btu/hr for each sq. ft. of rad area is a 9 section at 1/2 foot (.5 ft) wide, 3' high = .5 (1/2') X 3' = 1.5 sq.ft. X 9 sec. = 13.5 sq.ft. X 170 = 2295 but/hr heat output.

A heat calc loss for each room
is typically to assign 40 as a heat factor and multiply this by the square footage of the room---the total rad output of all rads in the room should approximate the room heat loss calculation.

Dan Holihan of Heating Help.com writes extensively about hydronic radiators and pipe distribution systems at the site below.


Re: Moving a Radiator.

I am learning how to calculate the heat output of a rad.

The room the rad is situated in is 10ft x 15ft = 150sq.ft.
40 x 150 = 6000, way more than the 2295 you calculated. What helps is that only one of the walls is an exterior wall and there are no windows. BTW this is the only rad in the room.

Thanks again.

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