Hi Guys, I have a Chiller R22 with a Dual Pressure Control that I can't Reset.

[Larry D. Hays]

I received a service call on a Chiller with circulating pump that provide cooling water to the rollers in a Printing Press. This Chiller has not been running for some time, months. The temperature range it operates in is 57 º to 63 º. I found the Johnson Controls Penn Type P70MA-1 has tripped on High Head pressure cut out. I tried to depress the reset button and reset it, but to no avail it will not reset. I jumped the switch to run the compressor as I observed the sight glass. When it had run for a few minutes and came up to run pressures and temperatures (57º cut out and 63º cut in). The Sight Glass remains clear and filled, no bubbles. The moisture Indicator is dark green, but I have tried resetting the hi side cut out that is tripped but to no avail.
I can aid the reset mechanically by using a small screw driver and pulling the pressure bellows and spring toggle lever as am depressing the reset button. This sets the Hi pressure cut out mechanically, but the switch is still open. Does anyone have any suggestions? Larry
This is My first post I want to say I'm how glad I am to have found this Forum. Hello to everyone!!!

[Brian_UK]

Welcome to the forum Larry, I have moved your post from where you originally placed it as no-one would be able to read it there.

Possibly the pressure switch is faulty but without knowing what the pressure is at the switch it is hard to be precise.

[The Viking]

Larry,

As you haven't provided us with any pressure data, I assume you are not actually used to work on refrigeration circuits...
With the problem you describe now is really the time to call in a professional.

Sorry.



.

[install monkey]

http://cgproducts.johnsoncontrols.co...DF/2486070.pdf
get some gauges on it to see what its doing- it could be short of gas and going out on lp- you can set the pressure switch to auto reset on hp fail but i wouldnt recommend this- bellows on the switch my be weak- comfirm stable running pressures ensure its running correctly then mybe tweek the rating- but check the rating of blow off relief valves- fusible plugs and maximum test pressure-

[cold.man]

As said you need to put some gauges on and seee what you pressure are.
Check what pressures you have and see what the settings are on your switch, as you may already know pressure switches should always be checked and set up with the gauges on the systems.
Sounds as the switch is faulty or been worked on in the past and not set up correctly and as install monkey said you need check the ratings of the prv or fused plug.