Steam Boiler Automatic Water Feeder's
There are many different types of automatic water feeders available today. The different types include electric, electronic and mechanical. There are also different feed rates for these products. Some feed as low as 1 gpm and some much faster. Automatic water feeders are designed for residential products, commercial products, and some for either. When choosing an automatic water feeder, you will want to match it to the proper Low Water Cut Off (LWCO). For example, you would match an electronic feeder with an electronic LWCO and an electric feeder with a float type LWCO and mechanical feeders to a float type LWCO.
There are automatic water feeders like the Hydrolevel VXT-120v or VXT-24v, that you can program to set to feed the proper amount of water to get back to the NWL. Residentially I prefer these over the other types if the owner cannot get to the basement to look at the water level. The water level will still drop below the best operation level but when the LWCO activates the automatic water feeder it will feed water until the manufacturers NWL is met if that is where you have it programed
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This is normally done by adjusting dip switches. The other thing that sets the Hydrolevel auto feeder apart from the others is an electronic water meter. This is important on newer steam boilers and most manufacturers do suggest adding a water meter to residential steam boiler feed system.
If your told you do not have to check the water level on a steam boiler here is the problem. Most LWCO's call for water when the water level drops below the probe on the LWCO. The LWCO will activate the feeder and add water until the water covers the LWCO probe. The auto feeder will shut down the water flow to the boiler. The Hydrolevel LWCO will operate the same way unless you move the dip switches. The feeder can be set to bring the water level close the NWL specified by the manufacturers. Following the directions on the auto feeder the LWOC dip switch would be turn off and set the flow in minutes. They explain clearly how to set the dip switches in the control installation directions.
Why is this so important? What a steam boiler is installed the manufacturer specifies the NWL that is a good place for steam production. The Hartford loop is to be piped 2" below the Normal water level. The Minimum distance from the NWL to the boiler header is a minimum of 24". If the NWL is not maintained and left to operate at the probe location those measurement will now be incorrect.
This is a fictitious boiler so the levels may not be accurate for your specific product, illustration purposes only. Maintaining incorrect water levels can affect the steaming of the boiler and shorten boiler life due to the amount of superheated iron above the incorrect water line.