Manual Reset Presuretrol

metro

Hello People,

I have a Manual Reset Pressuretrol that was required to be installed on an apartment house one pipe system boiler. It was set at 5 LBS., but what should the differential setting be set at. Since the unit was installed is has gone off on reset twice.

Thanks in advance.

metro

Dave_74

Manual Reset Hi Limit

A manual reset high limit pressuretrol should not have a differential. It's purpose is to shut the system down when the primary pressuretrol fails and pressure continues to build.

When it reaches set point, it should disable the burner and leave it off until reset (manually). This gives one the opportunity to check the primary control and see why it did not do its job and cut the burner out.

It is possible in your case that the primary pressuretrol was set too close to the manual reset pressuretrol, causing nusance shutdowns.

For your 1-pipe steam system, the primary pressuretrol should be set at 0.5 PSI on to 1.5 PSI off. I would recommend that the manual reset high limit pressuretrol be set at 10 PSI, insuring that this control will not cause unwanted shutdowns.

will smith_4

All pressure and temperature controls have a cut-in and cut-out event-they have to. Even a manual reset has to have a minimum cut-in point; if the boiler cycles off at 15 lbs for some reason (failed operator, jumpers...) the pressure still should be allowed to drop to a set point before the reset button will actually reset. Honeywell provides us with adjustable cutouts and cutins because they have to make a jack-of-all-applications (within reason) which can satisfy multiple applications/code jurisdictions.

Empire_2

Will I agree But.

I think the diff. on the man reset controls are factory set and non-adjustable. Do you agree? I've seen both but the pressuretrol for the steam should not be customer friendly that is why I think the diff is fixed. Correct me if I am incorrect.

Dick Charland

Correct

Mike you're correct, why would you have a cut-in setting when the control is designed to "lockout" so to speak on cut-out. It is not an operating control, but a manual reset limit.