McDonnell & Miller Universal Water Feeders are ideal for use in residential or small commercial applications. Versatile and compact, they are easily installed to operate with either a probe- or float-type low water cut-off. The feeders are always ready to add water when given the signal from the LWCO - no need to manually add water. And they protect the boiler from a dry fire condition by maintaining a safe minimum water level in the boiler should a system leak occur. They monitor the water level, maintaining a safe minimum and allow the boiler water line to rise and fall naturally through its normal operating range.