Replacement Vent for old convector copper fin style radiator?

HandyFS

This old hot water convector copper fin style radiator has this style air bleed valve/vent and I wanted to see if possible to replace with something else? It started to leak a tiny bit on the top screw after I had to bleed the system multiple times. It has now stopped leaking so all is well, but I'm thinking ahead since I periodically need to bleed the system since I'm still doing repairs over time. I didn't try to put thread sealant or anything on the screw, maybe that would work.

Assuming this was some type of air compartment that would capture some of the air in the system to minimize water hammering as an auto vent, or some similar function?

What is a suitable replacement vent? Is something like this recommended?
https://www.supplyhouse.com/Jacobus-Maid-O-Mist-67-1-8-Auto-Vent
https://www.supplyhouse.com/Caleffi-502640-1-2-Auto-Air-Vent

EBEBRATT-Ed

What type of expansion tank do you have? A steel compression tank you can only uses manual vents. A bladder tank and you can use auto vents.

What I would do in your case either way is remove the old vent and install a ball valve with an auto vent. You can keep the auto vent shut off if need be. see attached from supply house.com

HandyFS

Thanks Ed. Your knowledge AND time are appreciated.

Almost certain it is a bladder style expansion tank, looks like the typical Amtrol Extrol tank but I'll double check. In your suggestion, would the ball valve go on the supply line underneath where the convector connects to the supply? It is old black pipe and I'm hesitant to touch that connection.

Could I put an auto vent like the Caleffi directly into the top of the convector where the current vent threads into the top?

hot_rod

This is a good option. It is both a manual vent and an auto vent. You can also unscrew the top part for service or replacement. It has a ball check on the bottom part to allow removal without losing pressure or water. 1/8” NPT.

HandyFS

hot_rod said:

This is a good option. It is both a manual vent and an auto vent. You can also unscrew the top part for service or replacement. It has a ball check on the bottom part to allow removal without losing pressure or water. 1/8” NPT.

Thanks, nice other option to consider for sure.

At first I wasn't certain if this existing vent was doing some type of pressure equalizing in the system and needed to stay partially, but now it seems I can get rid of the entire thing down to the opening on the vector so I'm going to see how I can get that out and get a new vent/bleed in place.

As of now its not leaking, but, I saw it leaked so I know its capable so I may as well swap it sooner than later.

hot_rod

A vent in that application, high point, or point of use, should not need to be used often. First fill, after a draindown, maybe the seasons first start.

If air needs to be vented there often, look for an inadequate central air purger at the boiler. Or one that is piped wrong, or plugged and not working.

HandyFS

hot_rod said:

A vent in that application, high point, or point of use, should not need to be used often. First fill, after a draindown, maybe the seasons first start.

If air needs to be vented there often, look for an inadequate central air purger at the boiler. Or one that is piped wrong, or plugged and not working.

Thanks for the feedback. I'm mainly venting here when I an doing a partial drain down. I've been doing repairs to the 2nd floor zone so I'm introducing air into the system. After a few weeks of running I checked the cast iron radiators and straight water came out so that's a good sign no extra air is being introduced.

I do however have some more work to do on this system, so I need to bleed 2 of these convector style radiators, so I will probably swap out the vents depending if this one keeps leaking or not as I bleed it again.