Do I need to add water?

Rodney Summers

We have an old hot water boiler furnace with radiators throughout the house. During the beginning of the winter the upstairs was not heated adequately. I then purchased a bleed key and bled all the radiators. This seemed to help. None of the downstairs radiators had any excess air but the upstairs did. In some of the radiators then air drained but water never came out. This leads me to believe that there's not enough water in the system. Also, at night we can hear the water moving in the radiator in our room. I hope I didn't cause more problems by bleeding the radiators.

There's an expansion tank above the furnace, and there wasn't any water in it when I checked yesterday.

So, should I add water and if so are there any instructions anywhere on how to do this? Besides that the furnace seems to be running great. We have the thermostat set low yet the downstairs stays comfortable even after the boiler shuts down.

I'm also new to this forum, so I apologize for not being familiar in general with boiler furnaces.

Thanks,
Kevin

Timco

There should be a gauge on your boiler, and it should read about 12-15 pounds for a two story home...It may read some pressure, but that may just be the weight of the water. Find the fill valve and open it...but only fill a cold boiler. Never fill hot.

T

Mike T., Swampeast MO

Also, fill slowly and watch the gauge carefully. Once the pressure reads 12# (1-3 story house with 10' avg or less ceilings) stop filling and bleed all the radiators.

Then check pressure. If you've removed a lot of air the pressure will now be lower. Fill VERY slowly up to 12# of pressure.

If you shoot over 12# there should be a boiler drain (looks like a hose connection) near the boiler. Drain water until you get down to 12#. If you overshoot too much you'll lift the temperature/pressure safety--not pretty--that's why I say fill SLOWLY. If you can't see the gauge from the fill valve location I'd sincerely suggest two people.

Mike T., Swampeast MO

The fill valve is usually on the smallest pipe leading to the boiler but NOT the pipe leading to the expansion tank. The fill piping will come from the domestic water for the house--not from the heating system. If you're lucky, it's labeled...