Properly Balancing a One Pipe Residential Steam System
Many of you believe that balancing a residential steam system has to do adjusting the automatic radiator air vents dependent on the radiator location. Unfortunately this is not really the way to balance a steam system. You should be adjusting the air vent dependent on the size of the radiator. An important tip on balancing a single pipe steam system, verify there are working main line vents. Below is a Hoffman and Gorton main line vents.
Steam system efficiency is all about venting. The steam is produced in the boiler and must move to the end of the steam main first. The only way to get the steam to move through the insulated steam main is to vent the air from the main. Yes, I said insulated steam mains. No steam system should be operated without insulated mains as it can create multiple issues.
- Noisy systems
- Slow heating
- Systems that cannot be balanced
- No heat in some areas
- fuel bills
Venting One Pipe Steam Mains
The main line vents vent much faster than the radiator vents. It may not be unusual to see multiple main line vents connected near the end of the steam main. They come in different sizes and shapes.
It does not matter if there is one or multiple main line vent(s), they should never be at the very end of the steam main Stay back about 6” to 12” from the end of the main. Raise them as high as you can within reason.
Venting Radiators
Ahhh, now we’re getting somewhere. All this radiation can be connected to the same single pipe steam system. It is imperative that all the radiation is vented with a radiator vents. I have always liked the adjustable style radiator vents. All the radiator vents should be the same manufacturer and style.
In the heated rooms of the home there will be maybe one, two or more radiators. Contrary to belief it does not matter if the radiator is on the first floor, second floor, closer or further from the boiler. Balancing the one pipe residential steam boilers has nothing to do with geographically where the radiator is in the home but the size of the radiator.
It is fairly common that is a residential steam system if you look at all the radiators in the home they may all be 3 – 4 different sizes. This makes it easy to balance. For example, let’s assume there are 2 nine section radiators, 4 six sections radiators and 4 four section radiators. Again, ignore where the radiator is in the home. Verify you have good working main line vents. The only thing we are concerned with is vent the largest 2 radiators, set the radiator vent wide open #9 on the air vent scale. The four 6 section radiators maybe set to #6, and the 4-four section at #4 on the radiator vent. Explain to the customer that if a room is a bit too warm close one number or it too cool open 1 number and wait about a week before making another adjustment but only one number at a time.
One last thing, a radiator that would be 30 sq. ft. of steam or larger. One radiator vent may not be enough vent. It is a good practice to add a second vent to any radiator larger than 30 sq, ft. steam. Drill and tap the second air vent below the existing air vent. The second reason to add a second air vent is due to a very long pipe from the steam system main to the radiator.
Disclaimer: The information found on this web site is for informational purposes only. All preventive maintenance, service, installations should be reviewed on a per job situation. Any work performed on your heating system should be performed by qualified and experienced personnel only. Comfort-Calc or its personnel accepts no responsibility for improper information, application, damage to property or bodily injury from applied information found on this web site.