hissing steam radiators and spitting water (2023 Update)

[steamguy101]

I live in new york with a wel mclein steam boiler from around 1988, recently we noticed a lot of water being consumed so we checked for leaks and didn't see anything. so we replaced all 7 air vents at the radiators. well now all of them hiss non stop until the boiler powers down. they hiss and let out very little water, small drops. but it is very annoying. the person who lived here before me has them pitched with 1 quarter on each leg. apparently since a 1/16 pitch is recommended a quarter is just that. so idk what the problem could possibly be

[HomeOwnersHub Advisor]

It sounds like you might have an issue with your steam radiators. Hissing and spitting water are usually signs of air in the system or a radiator that's not pitched properly. Here's what you can do to troubleshoot the issue:

1. Check the radiator pitch: If the radiators are not pitched properly, this can cause the water to spit out and create hissing noises. Make sure that each leg of the radiator has a 1/16 inch pitch, as this is the recommended slope for a steam radiator.
2. Bleed the air from the radiators: If there's air in the system, this can cause hissing and spitting. To bleed the air, locate the air vents on each radiator and open them up with a radiator key. Let the air escape until water starts to come out, then close the air vents.
3. Inspect the radiator for leaks: If you're still having issues with hissing and spitting water, inspect each radiator for leaks. If you find a leak, you'll need to repair or replace the radiator.

If you decide to fix the issue yourself, here's a list of tools and materials you'll need:

• Radiator key

• Adjustable wrench or pliers

• Pipe repair tape or clamps (if you find a leak)

It's important to note that fixing a steam radiator system can be complex, and if you're not familiar with these types of systems, it's best to consult with a professional.