Could radiators be fitted with individual emergency drain outlets?

gliptitude

Would it be ridiculous to provide for local individual draining of a hot water radiator?

.. As in a third outlet installed on the radiator for the purpose?

Or as in when re-piping an old system with PEX or copper, could I put shut off valves on both supply and return and put a small tee for a drain in between the radiator and one of the shut offs?

I'm wondering because I've done repeated draining and filling of a badly damaged system in the past and am considering it again on another project. I presume draining and refilling poses risk of further rust damage.

.. In my current house I had a surprising radiator failure where one rusted through in the middle and had to be eliminated. Unfortunately I can't remember all the variables. 

I'm considering buying a particular house which has more radiators and a bigger system but there is some significant rust/corrosion/wetness on the pipes near the boiler, (not a problem I've experienced at the current house where the radiator rusted through). All pipes are currently threaded steel.

This is speculative inquiry and I'm not an engineer or contractor. I've just experienced multiple times in my radiator adventures, catastrophic failure and massive water loss/mess. These rusty pipes in the "new" house make we worry about the radiators and I wonder about a system upgrade that eliminates points of failure and isolates remaining weak points.

STEVEusaPA

Webstone makes a number of valves that would do that in sweat, pex, press. Just seems like a lot of work for something you will probably never need, or need once.
Upgrading new boilers with old systems usually necessitates flushing, chemical treatment, strainer and mag filter for best, long lasting results.

PC7060

What @STEVEusaPA said.  I routinely put cutoffs with drains on any radiator line I work on. Used to use the standard cutoff from big box store with the small drain cap before I leaned about the Webstone shutoff with house drain connection. 

EdTheHeaterMan

The first thing that comes to mind is that you need a valve on both the inlet and outlet of the radiator to isolate it from the system. Just adding a Tee or a third port on a radiator will drain the entire system above that opening thru the return pipe.

I know this is an unusual way to look at it but I have homeowners insurance to cover water damage from such a problem.

mattmia2

There is a european valve that is a shutoff that you can also attach a fitting to that allows you to drain through the fitting, but a valve with waste cap is more than sufficient for what you want to do.

JohnNY

mattmia2 said:

There is a european valve that is a shutoff that you can also attach a fitting to that allows you to drain through the fitting, but a valve with waste cap is more than sufficient for what you want to do.

Not so European. The most common one we see on the market is made by Webstone.