Boiler Pressure too high

Filbertsteam

Hello, this is my first post and my second season with steam heat. Last winter I learned through this wall and various books that Steam heat works better with less pressure, and my system did run better after I turned down the pressure on my pressuretrol. I have also added pipe insulation and replaced my main vents and most of the radiator vents as well.

My problem is that this year it seems the pressure is always higher than I have it set. I have a honeywell PA404. I set the main scale by bottoming out the indication and then turning the screw in the opposite direction so that I just saw it rise on the scale, about .5 psi. Then I set the dial to 1 psi. So I should be running .5-1.5 psi right? But the gauge on my boiler shows anywhere from 4-6 psi (I'll manually turn it off before it gets much higher). I don't think the gauge is defective because it seems like my system ran better last year when the gauge would show about 2 psi max. But I don't know how to confirm this. Is it possible the pressuretrol is broken? Or maybe the pigtail loop is somehow clogged up? Any help or advice on what to do next would be greatly appreciated.

nicholas bonham-carter

Over pressure problem

Definitely check the pigtail, get a 0-3 psi gauge (which you can rely on), and finally get a vaporstat. Put them all together on the same tree on top of the new brass pigtail.

On our new boiler, with a new pressuretrol, after adjusting the settings as low as possible, somehow the linkage disconnected, and allowed the boiler pressure to soar. A vaporstat was the only cure.

The gauge comes from gauge store.com, and is protected from steam by the pigtail.--NBC

JD424

Similar Problem

Hi I have a similar problem. I have the same Honeywell PA 404 and I am using the same settings. .5 Cut in with Diff set to 1. I noticed the pressure clime to 10 PSI when testing my system for the season after I performed a cleaning and flushed the wet return. It seems that the linkage is intact, do these units just go bad? Worked great last year when I adjusted it down.



What is the benefit changing to a vaporstat? Will my system be any more efficient by lowing the pressure to ounces? I have a one pipe Steam system. I thought the Vaporstats were more for 2 pipe vapor systems.



Appreciate the help, I have been learning a ton from this site and from Dan's books.



Electrician learning about Steam.

J

BobC

gauge?

As NBC said the pigtail should be removed and cleaned first, before putting it back use a coat hanger or something like it to check inside the boiler tapping it goes into to be sure there isn't any sludge in there that might flop over and block the tapping when pressure starts to rise. Look at the base of the removed pressuretrol to make sure the 1/16" hole at the base of the brass coupling is clear, I have seen them covered over and that stops the pressuretrol from seeng the pressure in the boiler.



The 0-30 PSI gauge is about the cheapest thing on a boiler and they do go wonky. If a system was really running at 10 PSI I think the noises coming from the radiator vents would alert you to a problem. Does the gauge read zero when it's cold?



The cheapest made thing on a boiler is the pressuretrol, they are inaccurate and the linkages do slip. With the boiler off and under no pressure you should be able to move the silver "beam that is below the spring (that you adjust for the setpoint) and the microswitch that controls the boiler. Use a small screwdriver and see if you can hear that switch click when you move that lever up towards the switch. Then turn the power to the boiler off at the circuit breaker and test the switch for continuity when it clicks.



Will a vaporstat save money on a single pipe system? Yes it will but it will take some time to pay for itself because they are not at all cheap. I bought an old NOS mercury bulb unit a few years back and am running it at 12oz for the cutout and 4oz for the cutin. I was going to have to replace my pressuretrol anyway so I decided to go for the vaporstat at that time and lucked out by getting one for a C note.



At that time I installed a 0-3 PSI gauge so I'd know exactly where my pressure was.



Bob

JD424

Thanks

Thanks Bob



Had to settle for the Pressuretroll and a new gauge, Wasn't in the budget for the vaporstat. I have a Pro coming next week to assist me with a tune up.



Thanks