Powerpile question

JM_2

The pilot went out a few times on my powerpile steam system recently. I called the gas Co. for service and they came and determined that the pigtails needed cleaning. The system has two pressuretrolls and two pigtails. One pressuretrol is into what looks like a tankless hot water set-up, but i am not using that.
My question is "why would a clogged pigtail cause the pilot to go out?"

Dale

could be

Sometimes the power pile is wired into a high limit, if the high limit opens it drops the power pile output. Some of the pp valves have 2 coils, one operator and one pilot safety. If the pressure trol on one of the pigtails was used as a high limit wired into the pilot safety and it opened the pilot flame would go out. A clogged pigtail allows pressure to get higher and not relieve.

Unknown

You probably have an auxillary

system that used one pressuretrol for boiler operation set at 2 lbs off 1/2 lb on. The other is functioning as an energy cut off wired into the pilot generator circuit to the pilot safety part of your gas valve. It is set to open at usually 14lbs off and 9 lbs on. If the pigtail was plugged it would open and that would cause the millivolts needed to keep the pilot power unit energized to "drop out" shutting off the flow of gas to the pilot.