Pressuretrol question

Bigpickle18

I had my pressuretrol replaced by my uncle who mainly only does new or replacement installs. He put on a honeywell pressuretrol with the mercury bulb in the middle. The cut in as at 7 PSI, cut out is at 6.

Is this to high? I’m looking at my old pressuretrol, a grey front, it was only at 0.5 psi

Does it need adjusting? My radiators are insanely loud now

bburd

Assuming this is an ordinary low pressure steam heating system you want it to cut out at no more than 2 psi, and 1.5 is better; and cut in at about half that. If you post a photo of the pressuretrol we can tell you how to adjust it; this varies by model. Also a mercury bulb pressuretrol must be set level or the calibration will be thrown off.

Some residential steam systems were designed for much lower pressures that require a more sensitive control called a vaporstat; these are usually two pipe and are most often found in larger homes and apartment buildings.

109A_5

Hello Bigpickle18,

Sounds way too high. The overall performance settings of the new pressuretrol should have been set to match what the old pressuretrol was set at, assuming the old one was actually set correctly, usually a minimal setting for residential steam heat.

The confusing part (since it is a different pressuretrol) is some have an 'Additive' differential and some have a 'Subtractive' differential (usually labeled somewhere on the pressuretrol) so the actual numbers for the settings on the new unit may be a bit different for the same pressure performance.

Since they sound like they are set way too high, it sound like he did not bother to set the new one. Was the old one actually bad ?

Also with the mercury bulb type pressuretrol, it should be level and the pigtail should be 90 degrees to the front of the mercury bulb type pressuretrol so the heat change imposed on the pigtail does not bias the settings.