We are in the process of ripping up an old wall-to-wall carpet on which a radiator sits. We want to disconnect the radiator so that we can move it to remove the carpeting, fix the flooring underneath and then put the radiator back. [The radiator is 84" long and 23" high.] After shutting off the valve at the radiator, we have been draining it via the bleeding valve. However, after 20 bucket loads of water, we are wondering if this is not the correct way to go about it. Any enlightenment would be greatly appreciated as we wish to avert a Niagara Falls in our bedroom. Thank you!