Broken Radiator Union Valves & Vents

It's worth trying to fix the stuck or broken valves. They do come apart rather easily… well, sort of easily anyway. And it's much easier than replacing them, as if you replace them you have to replace the radiator spud as well, which is a real pain.

The packing nut should undo easily. The bonnet nut (the square one) may require some persuasion. If so, be sure to use a backup wrench on the valve body (on the hex at the bottom of the body).

It's worth trying that first.

The vents can usually be unscrewed and replaced with new quality ones. Use them to balance the system. Most of them can be turned upside down to more or less seal the radiator, and reduce the heat from it to almost nothing.

Now. A word about closing off parts of the house to save energy. That's very attractive, but… keep enough heat in the closed off parts to make sure that you don't get any condensation. Typically holding the temperature above 50 or so works. Why? Because if you are getting condensation in there, all the fabrics are getting wet. Any plaster is getting soaked. Drywall is getting wet. The result? Rampant mold and failing plaster. Which can get VERY expensive in just a season or two. Repairing failed plaster in just one room can easily eat up the fuel savings from a decade…

There are both universal handles with multiple inserts for different broaches and handles to fit a specific broach.

@Gordo has a number of videos where he takes various radiator valve apart.

The bonnet does unscrew though it can be very tight so you may need some wrenches that fit well to get it apart. If you have all or mostly the same valve you might buy some open end wrenches in those specific sizes.

Be careful not to tighten the packing nut too much or you can split it. It is better to tighten it some, work the valve possibly take it off and add a little more packing, tighten it again and fill it littel at a time. If you dig the old packing out be careful where you do it and possible keep it wet because a lot of old packing contained asbestos.

@LegendsCreek , if the house was split into two zones, why not install two smaller boilers instead of one large one? This way you have better control, and redundancy in case one boiler doesn't work. We did that in a church some years ago, and their fuel consumption went down since they didn't have to heat the sanctuary unless it was being used:

I'm sure @Charlie from wmass could put something like this together. He's one of the best.

I know nothing about your radiator valves, but I do know how to fix stuff.

So with that said, if this valve stem is free to turn, and it rises and falls as the stem is turned, and you can get a good fitting handle to turn the stem, then all you need is a good fitting heat resistant rubber washer to fit in that recess. Oh yes, you will also need to replace the packing that surrounds the stem.

A good source for the packing is Ace Hardware's #40209 Graphite packing. One packet should be enough to repack all your valve stems.

For heat resistant rubber, I would recommend Ethylene Propylene which is good for 300* F. I have some scraps in 1/8 and 3/16" thickness I could send you which you could cut to size. That is, IF the Post Office will do their job and deliver the mail, something I'm having a real problem with these days.

Of course, as @Charlie from wmass says, New valves are the best answer, but may be more difficult to find and change out.

Hope this reply is helpful.

You can also buy string packing form mcmaster-carr in many sized and in a spool instead of the short lengths on a card. I'd use teflon for those.

The washer was probably leather originally — but a rubber washer (flat) will do. Almost any larger hardware store should have them. It fits inside the outer ring and over the nut — which, ideally, you should remove so it will slip over. That may be easier said than done — I suspect on that one the screw has to come out first…

You can measure with a micrometer or caliper and order washers from mcmaster-carr. You can always make the hole in the middle bigger if you have to. Teflon will last forever but it might not be soft enough to seal fully.

Once you have the bonnet off you can loosen the packing nut and work the stem loose with a wrench then you can take the stem out and clean with a wire wheel or fine scotchbrite and clean up the threads and then put it back together with a little silicone grease and you should be able to get them working if you're careful about not forcing anything to mcuh.