Hopefully this is the last of the problems I have to overcome. I have a 3 zone system with an old National boiler Model 3W-99A-PA, 60,000 BTU Input, 48,000 BTU Output, 41,700 Net IBIR Output.

The boiler runs too hot. It heats up to 180 degrees and kicks off the limit prior to the room temperature reaching the thermostat setting. Can the burner and/or gas valve be adjusted to reduce the output and lower the boiler temp? I wouldn't do this myself, I just want to know if it can be done.

Thanks

Sherm

 

Is this a trick question? Your boiler is acting normally.

The burner on the boiler has only two heat output settings, off and maximum. The maximum was (or should have been) calibrated to operate the system continuously when the outside temperature was at the lowest ever expected point. This is called the design temperature. At any outside temperature above the design temperature the boiler, along with the rest of the system will cycle on and off to maintain the desired indoors temperature.

Since its original installation many things may have happened to offset the amount of heat required in the home. Such things as new windows, weatherstripping, additional insulation and even learning (or desiring) to live with a lower indoor temperature will reduce the amount of heat needing to be added to the home.

Even a new building several hundred feet away from the house could have an affect upon how much heat is required to maintain the desired indoor temperature.

 

Thanks for answering a dummy's question.