[SOLVED] pressuretrol not turning off boiler

patrykrebisz

My pressuretrol is set to 2 (with differential set to 1.5) but my boiler didn't shut down until the room reaches the temperature set by the thermostat. At that time boiler's pressure gauge was showing 9 psi (starting from cold). From reading this forum it seemed most-likely culprit was clogged pigtails (we just bough the house and the boiler hasn't been maintained since 2021).

In the process of reading up on the issue, i ran into a bunch youtube videos by "Silent Steam Team". In one he shows how to test if your pressuretrol is doing its job.

Well, mine was NOT.

I replaced old pigtail (which was not clogged) and added 0-5psi gauge to the Y.

Before i put it all back on the boiler, i decided to test it on the bench. I would pump the pressure up to 5psi and… nothing. The switch would not interrupt the flow of current (thus not cutting off power to the boiler).

To fix it, as per one of the videos of above-mentioned youtuber, i adjusted the screw in the back of pressuretrol. Now all works fine.

Bottom line: pressuretrole straight out of the box might NOT be calibrated.

109A_5

Hello patrykrebisz,

I believe the "Silent Steam Team" is a member here and his videos are very informative. Sadly Pressuretrols are notorious for various malfunctions.

Glad to hear you were able to get your system working better and learned how to test it.