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Pressuretrol issues

Poilar Member Posts: 1
edited December 2016 in Strictly Steam

I have a Honeywell PA404A pressuretrol attached to a 0-30 gauge and a pigtail. The pressuretrol, though set to cut in at 0.5 and cut out at 1.5, tends to cut out around 4 and cut in around 3.5. From what I've read on here, I should do the following:

1) Check if the pigtail is clogged;

2) Install a 0-3 gauge (in addition to the 0-30) to check if the 0-30 gauge is accurate;

3) Maybe replace or recalibrate the pressuretrol.

Am I on the right track?

Also, the system is set up such that the pressuretrol is as appears below, so I can't unscrew the pressuretrol on its own because it is too close to the boiler. Is there any reason I can't just unscrew the pigtail (and with it the gauge and the pressuretrol)? Once the pigtail is off, it would be easy to separate the gauge and the pressuretrol.

Thanks so much!


  • Fred
    Fred Member Posts: 8,518
    edited December 2016
    You are on track. Yes, you can take the pigtail and Pressuretrol off as a single assembly and then separate them to clean the pigtail. Don't clean the pigtail with it on the Pressuretrol as you will likely push crud up into the Pressuretrol orifice. Check the small orifice on the bottom of the Pressuretrol too and make sure it is not clogged.
    Re-Calibration Procedure:
    Inside the Pressuretrol, right below the micro switch, there is a pivot arm. At the end of that arm you will see a screw pin that is activated by the diaphragm at the bottom of the Pressuretrol. If you look very carefully at that screw pin, you will see it actually has a tiny (I mean tiny) hex head on it. It takes a .050 hex wrench and you can turn it clockwise (Towards the bottom of the Pressuretrol to decrease the Cut-out pressure or counter clockwise to increase the cut-out pressure (which none of us want to do but who knows, your Pressuretrol may be really screwed up!). Turn the power to the unit off first. You may find the first attempt to turn that screw a little bit stubborn (relatively speaking) because it has some Locktite on it but it does turn. Don't turn too much, a tiny fraction of a turn goes a long way towards getting it adjusted where you want it (maybe 1/32 inch turn to start with) . You may need to play with it to get it exactly where you want cut out to be.
    If the little set screw is frozen (they use Lock-tite at the factory). Use a soldering iron to melt the lock-tite.
    EBEBRATT-Ed Member Posts: 9,018
    Do as @Fred mentioned above. In addition when you put it back on (the pressure control) put a 1/4" brass union and (2) 1/4" brass nipples between the control and the pigtail.

    It will be easier to remove and clean the next time and you won't have to remove the wiring.

    You can steam the boiler with the pressure control removed for a miniuet to blow out the pigtail.

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