Honeywell Pressuretrol Issue

ImYoungxD

I recently purchased a house and having problems with our pressuretrol. I've attached some images.
I currently have the cut in at 0.5 and differential at 1. However, the PSI gauge reaches up to 7 and then turns off. It turns back on after 30 minutes when the radiators are cool and at 0 PSI for a while so it doesn't heat up the house very well. Maybe the PSI gauge is bad? Boiler is less than 5 years old. Could be 3 years. Not sure if pressuretrol was replaced as well. House is almost 60 years old. Previous owner had cut in at 2 PSI before.

Yesterday, I took off the pressuretrol and pigtail to give it a good cleaning. I will be getting a brass pigtail soon to replace the current one. The current one had lots of black muck and I gave it a good cleaning. Water can enter and leave easily now. I installed the parts as usual and now the pressuretrol won't turn off the boiler after 5 PSI. I had to tap the pressuretrol for it to turn off. After 30 seconds later, it turned back on while it was over 4 PSI! I always leave the water level little above 1/2

Now I need help. What did I do!?
Boiler usually stays on for 45 minutes during a cold start but now it's been going over an hour. I manually shut it off now and worried it might break something.

https://imgur.com/a/oeO4C

I think my workplace blocks me from uploading my images at strange sites so I have to post a link

Jamie Hall

Three possibilties. First, is the little port at the bottom of the pressuretrol clean? If the pigtail was gunked up, it's possible it was, too. Be careful ungunking it not to damage the diaphragm inside. The second possibility is that the linkage in the pressuretrol gotten disconnected. That's a bore, but fixable. I don't like to set pressuretrols below 0.7 cutin for that reason. The third possibility is that the pressure gauge is lying. They do sometimes...

So. Take the p'trol off again (sorry!) and double check that the pigtail is clear into the boiler and that the little opening is clean. Then look and make sure that the linkage inside is attached. Then get yourself a threaded T, a few nipples, a couple of elbows, and a 0 to 3 psi gauge and mount the gauge and the p'trol on the pigtail. Nice project for an evening...

ImYoungxD

Thanks Jamie
-I cleaned the pressuretrol and the opening was not blocked. I'll take a look again. Any recommendation on cleaning the small hole if there is blockage?
-What is the linkage? It is the spring that attaches to the bottom of the spring of the cut in adjuster? If yes, it is attached
-I'll buy the parts to install another gauge for the pressuretrol.

I saw on another thread that I can adjust the small screw below the differential knob by turning it clockwise 1/32 of an inch until I get a satisfying result. Is that fine to do so?

BobC

Pressuretrols can be off by quite a bit, make sure the linkage is still good. I would make sure that gauge isn'y lying before making any adjustments. Once your sure you will need a 0.05" allen if I remember rightly.

Bob

ImYoungxD

I saw on another thread that they forgot to add water to the pigtail. I did not do that either. I guess I should when I go back home

Fred

The loop in the pigtail will condense steam and hold water. Adding water isn't really necessary. The diaphram in that model Pressuretrol is a metal one so you aren't likely to damage it. Use a straight pin to clean the tiny orifice.
Yes, you can re-calibrate the Pressuretrol. Here is the 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 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.

ImYoungxD

Thank you Fred, I will probably do that as a last resort.
I also noticed there were blue grease on the screw pin. Should I leave that alone?

Fred

Is it grease or some type of locktite? Most have a Locktite holding that tiny screw in place. If grease, just wipe it off and do the calibration when you feel you are ready.

Gsmith

You might want to investigate why your system needs to run at such high pressure. Most older steam systems were designed and actually constructed to run at very low pressures and if properly set up and maintained will not trip the pressuretrol except perhaps on startup from a pretty deep setback (if you have your thermostat set to be lower at night for example). The pressuretrol is there as a safety device to shut off the boiler if the pressure gets abnormally high, and not really as an operating control to start and stop the boiler--the thermostat should be doing that. I notice your near boiler piping is not insulated. Are the steam mains insulated and are there decent vents on the ends of the steam mains. If you have not read Dan Holohan's books, available on this website, like We Got Steam Heat or the Lost Art of Steam Heating, they would be a good place to start to learn about how and why steam systems operate a such low pressures and what might be missing or knuckleheaded over the years in your system. It's always possible the pressuretrol is bad, but since these systems are normally designed to operate at very low pressures (less than 1 psi) I'd spend a little time trying to figure out why your system seems to need to operate at so much higher pressure.

ImYoungxD

I took apart the pressuretrol and pigtail again. Inspected them and they were clean. I blew into the pressuretrol and it is ticking. Reinstalled the parts and it looks like it's working better than before
Boiler cuts off at 3 psi, turns back on at 1.5
Current gauge could be bad so I'm waiting for a new gauge to be delivered. I have the tee pipe, nipples and an elbow.

I noticed my pressure drops quite fast and the boiler cycles back up between 1-2 minutes. Stays on for 5-10 minutes and then off, turns on in 1-2 minutes and so on until it hits the temperature. I know one vent is not closing when the steam hits it so that's going to be replaced.
I hope that will fix all the problems.

Thanks for all your help

nicholas bonham-carter

The pressure still appears too high at 3 psi, which makes it difficult for the main vents to close when steam hits them.
I had the same problem with a new pressuretrol on a new boiler. This was before Fred’s excellent instructions, and when adjusted down, the linkage disconnected, and pressure raced up. The solution was to get a vaporstat, and a low pressure gauge.
Over pressure also creates a problem with the height of water in the wet returns, starving the boiler a bit. For each ounce of pressure, the water rises 1.75 inches in the wet returns-quite a volume in today’s low water content boilers. —NBC

Jamie Hall

ImYoungxD said:

...

I noticed my pressure drops quite fast and the boiler cycles back up between 1-2 minutes. Stays on for 5-10 minutes and then off, turns on in 1-2 minutes and so on until it hits the temperature. ...

That cycling, once the pressure is up, is quite typical -- and the timings suggest that the boiler is rather close to the correct size and firing rate. That is, assuming that that is happening once all or most of the radiators are hot.

Gordo

@ImYoungxD :
Got a video of testing a Honeywell Pressuretrol that may be of use to you. Hope it helps. Please let me know.
https://www.youtube.com/watch?v=mE1-QuUx4_c&t=10s

BobC

Good video, I wonder how far off it is at the high end of the scale.

For the price they charge they should have better quality control.

Bob

Fred

Mine was off by 7 PSI before I recalibrated it. That's what surprised me about @nicholas bonham-carter 's comment that he had to adjust the screw so much that the link fell off. I would almost have to guess his Pressuretrol simply died and couldn't be adjusted.

ImYoungxD

@Gordo
I saw that video and also saw this one from the same uploader
He did some adjustments and mentioned this forum on one of his reply. I am guessing it's Fred's method. I will be doing this soon.

https://youtube.com/watch?v=3vceuKfVg9w

ImYoungxD

Annual tune up guy came up last weekend and changed the nozzle. Says the previous one was causing the pressure to build up too fast or something and changed it. Says I won't notice much. Not sure if I'm saving more oil but it's taking around 60 minutes at cold start for the boiler to turn off now (normally 40 minutes). I noticed there is less steam hammer than before so that's good.
He increased the pressuretrol cut-in to 2. I changed it back to 0.5 after he left. Steam is taking a bit longer to heat up the rads but am I saving oil with a different nozzle?

He suggested I change the main vent which I will to Gordons #1. It should be better when I get the new main vent.
He also suggested I use some boiler cleaning chemical to clean out the scale and rust in the return. I have some liquid cleaner from Home Depot but I don't know where to pour it in. I can't remove/open the safety valve. Any suggestion?

@Fred
I thought the blue stuff was grease since it was shiny. I calibrated the pressuretrol with your instruction and it's more accurate on the 0-30 gauge. Boiler shuts off around 2 psi and turns back on around .5 -1psi. I am waiting for the 0-3 gauge to be delivered for more accurate reading.
Thanks

Jamie Hall

I'm personally very doubtful about adding any chemicals to the boiler water, although some folks find Steamaster to help. Unless the water in your gauge glass is really cloudy -- really cloudy -- I'd skip that part.

MilanD

FWIW, before I replaced it with a vaporstat, I had to physically bend down the little lever above the pin on the pressuretrol arm that meets the pin just to get it to be more accurate. 0.5 on the dial and 1 on the wheel still had it go to about 3 psi! And I wasn't able to remove the gook that was on the calibrating set-screw. That metal is quite soft so it's not too hard to do. A low pressure gauge is a must to get it done accurately and it's a bit of trial and error.

Fred

@MilanD ,You never want to bend any of the indicators on a Pressuretrol. When you do that, you lose all points of reference. The indicators/pins are properly set, at the factory. They just do a lousy job of calibrating, if at all. If the glue is hard to get off, a little heat from a soldering iron works well.
@ImYoungxD , I'm glad your were able to re-calibrate to a reasonable range. When you get your low Pressure gauge, you can fine tune further.

MilanD

@Fred - yes, I had to re-mark with a sharpie the new 0.5 setting on the trol, but I didn't find it to be confusing.