Thank you for the video! I was interested in the construction of these valves and your videos fit the bill perfectly! Three years ago, as a first time homeowner, we purchased the cheap "IPS Angled Adjustable Steam Radiator Valve" to replace the broken one on our bedroom radiator. It split right along the seam a few weeks back. Sounded like a whistle train when it failed. Three years in service isn't too bad but, I figured that there must be better models. We just purchased a Gorton replacement.

I've found that there are 2 variations on the cheap USAV-884 vent. The smaller diameter one with the small adjustment screw, and the larger diameter one with the large adjustment screw. The large one is of considerably better quality and I have actually found they do a much better job of sealing against wet steam than others. At least until the bad near boiler piping can be fixed. The Durst SRV from Lowe's which is a Gorton clone is also useful for balancing a system. It comes with every size of orifice for $10. Would I use these on a properly running system, probably not. But to limp a leaky boiler through the winter they absolutely work, as well as to balance a system without buying a bunch of expensive Gortons. When they break they can be replaced with the real thing, now that you have an idea of what vent should go where.

Thanks Gordon! Very informative video!

I still use Hoffman 1A's but use Gorton nos. 1 and 2 for mains and for hard to vent rads that are further off the mains and risers. 40s don't seem to vent fast enough, although sometimes slow is good. Thanks.

Would love to see you compare other models

Thank you for showing us the insides of these vents and how they work! Much easier to see than “theory” or drawings in a book. And how do you get such nice cuts when you cut them in half???

Very useful video. We have a steam radiator on the 4th floor that lets out air very very slowly. Is it possible to move the air out faster by adding 2 vent valves or a different one that moves air out faster?

Have you tested that Hoffman 2A valve to see if it holds vacuum?

I have hoffman 1A in my home my local dealer only have Hoffman 40, are the 40s ok to replace the 1As?

How would you know if the ones you have, need to be replaced or not ? Thanks in advance.

Another good one, Gordon. Have you been using Groton vents?

My steam radiator has the standard Hoffman vent but the apt building is pre-war so the vent threads on the radiator itself are old and corroded so that it doesn’t tightly lock into place. Tonight the steam/pressure blew the Hoffman vent off of my radiator and now my bedroom is a sauna & the radiator is spitting water. Called my super but any tips on the interim? I’ve already tried tape on the vent threads and pitching the radiator as much as I possibly could

I'm going to be installing a main vent on a small one pipe system. I'm thinking, Gorton #1 or a Hoffman #4A. There's a 1/2" tapping conveniently located on a tee, 15" from end of the dry return before it drops to the Hartford loop. Which vent would you choose?

General question... as a rule of thumb how often should someone replace the air vents?

My hoffman No 40, air steam vent, has started to spit water. I don't know what else to do because I have taken water that was inside, but it's still doing the same.

Should the valve point up or down ( the hole at the end) when connected to your radiator? Does it matter?

The Bob Ross of heating.

Thanks for the video! It's very helpful! One question, one of the #40 vent in a radiator in my home is getting very loud recently. Is it normal? Thanks in advance!

Any advice on how to size air vents for heating coils for roof top units? Got a new job recently and finding a lot of screwy stuff here and I’d like to make it right.

Do u recommend this #40 air vent on vintage radiators ….. the boiler I have is from 1960 (peerless) …. A couple of years ago I needed up buying Dole air vents .

Hi Gordon, I live on the 3rd floor and have steam heat, would you recommend the Hoffman #40 for all 9 of my radiators? As it is now I have those cheap Maid of the Mist ones and some radiators are not heating.

can i replace a hoffman n40 with any other Gorton if i don't like this design? my large living room radiator is not heating up. maybe got water in it. the coming neck area is warm/hot, radiator is cold.

Quick question, Gordon…….do you recommend cleaning these on occasion using the “ Soak in Vinegar” method?

Never buy junk steam valves from any big box store, go to a plumbing supply house...

Hi, I just had a radiator service and had Hoffman #1As replaced with #40s and since this they all whistle and sputter. I can see steam and little droplets of water sputter out of the hole and eventually it just starts whistling, like a tea kettle with steam coming out of the hole. Do you know if this is normal? I didn't have this issue with the #1As.