Should my pressuretrol be shutting off the system, and what could be keeping it from working?

paweiss

tl;dr is it possible there's gunk inside blocking the pressuretrol port, even if I can't see it?

Hi - Burnham steam single pipe system, 3rd fl apt. After turning up tstat, fires up, takes about 10-15 minutes to start getting radiators warm; good and hot after 20-30 min. Boiler running this whole time. By 40 min or so, steam is angrily pushing through the radiator vents; the pressuretrol still isn't shutting down the system. I would think it should be by this point? The pressure gauge (separate port from the trol) gets up to 4.5 lbs, which I understand is way too high, if it's accurate. It's somewhat suspect though because it sits around 3 lbs when cold. I tried to remove it to inspect, but can't get a good grip on it with the wrench I had, and/or it's too rusted into place? I replaced the pressuretrol ($220!), but the new one acts the same . I have it set to 1lb cut in, 1lb differential, just like the old one was. I cleaned out the pigtail; I think it's steel, and I tried to replace w brass, but the one I got was too short. But water runs very well through the pigtail now, so it seems pretty good.

I'd like to get a working gauge; I'd like to put a lower range gauge on the same pigtail as the pressuretrol too, to help me understand what's going on. But right now, I'm trying to figure out where the problem lies. How possible is it that there's gunk blocking the port for the pressuretrol somehow? The port is slightly higher than the top of the sight glass; the water level is about 3/4 up the glass. I know it got overfilled at some point a few years ago because the sight glass connections were plugged up with goo. I've cleaned those out, and the pigtail before as well. This time, when I took off the pigtail, expecting that to be the problem (it wasn't great but it also wasn't nearly as bad as when I cleaned it a year or two ago), I did look a little in the port, and didn't see anything obvious. Should I be more agressive in seeing how that looks in there? I'm afraid to poke too much without knowing it's ok. I've heard it's somewhat normal to have some gunk in the boiler, but does this sound beyond the normal range?
Thanks,
Philip

EdTheHeaterMan

sounds like the system is operating as designed and you have a gauge that is out of calibration. If, at no pressure, the needle is on 3 and then it moves to 4... you have about one pound of pressure in your system.

The pressure control set a 1 PSI with 1 PSI differential is actually set at 2 PSI High limit or cut off. It will then allow the burner to restart when the pressure drops back to 1 PSI.

If you are not one to "go with the flow" or must have the exact measurement to feel complete with the world order (as I am), then you need to replace the gauge. If however, you are easy-going and able to adapt to the inconsistencies of the world, then let it go... if it ain't broke, don't fix it.

Put a Post-It on it that says 3=0 4=1 5=2

There I just fixed it. That will be $125.00 plus 3 cents for the Post-It
Inflation is a ****! LOL

paweiss

Thanks. I was wondering if I should consider the gauge reading as just translated up 3psi, and then you're right, that at 1.5 lbs, the pressuretrol wouldn't cut out yet. But, it sure seems to be running at too high a pressure? I'm sure I don't fully understand how the vents on the radiators are supposed to work, but I'm pretty sure they shouldn't be loudly shooting out large amounts of steam? I just replaced all the vents, thinking that clogged vents were my problem. So, either the vents are all (6 of them) faulty, or the pressure is way too high I think?

EdTheHeaterMan

You could try setting the control at .5 psi with 1 psi Diff. If the furthest rads are heating and there are no other "cold radiators" in the system, then 1.5 psi might be enough, and it may also reduce the fuel cost slightly. You want the Diff as high as possible to reduce short-cycling, assuming the pressure ever gets high enough to cut off the burner.

ted_p

I'm guessing that you currently have the standard 0-30psi gauge?

If so, you should consider replacing it with a 0-3psi gauge. Even a good 0-30psi gauge lacks the accuracy and resolution necessary to make it useful when checking or adjusting your pressuretrol.

paweiss

Ted: Yes, it has the standard 0-30psi gauge. My understanding is that code requires that one, and if I want something more useful to me, I can add it _in addition_ to that one. That's my plan; to add a 0-5psi or something on a T with the pressuretrol, but I haven't been able to find all the bits and pieces yet. My local supply houses HATE dealing with non plumbers.

paweiss

Ed: I tried setting it as low as I could, but that didn't make a difference. I'd also read somewhere that the pressuretrols don't work reliably when set down below 1psi.

Grallert

Maybe you mentioned it and I just skimmed over it but you might not be venting the main/s quickly or at all.? The radiator vent should not be venting steam and you should hear a satisfying click when the steam reaches them.

paweiss

I didn't find a main vent, which confused me, but I guess I've read that they're not always used. I didn't notice a click in the radiator vents, but I wasn't really listening for it; I'll try that. If all 6 new vents are venting steam, so you think it's:
(1) that they're all faulty
(2) that I'm imagining it
(3) that the pressuretrol isn't shutting off the boiler and the pressure is way too high (I'm thinking that enough overpressure would push through a vent - is that feasible?) [bad pressuretrol/blocked pigtail/some other blockage]
(4) something else I haven't thought of.

ethicalpaul

> My local supply houses HATE dealing with non plumbers.

supplyhouse.com

KC_Jones

ethicalpaul said:

> My local supply houses HATE dealing with non plumbers.

supplyhouse.com

Agree with this. They have great customer service and for me, are significantly cheaper than my local guy.

Jamie Hall

With regard to your assumptions/question, @paweiss
1. Quite possible, depending on where you got them. Big box, good chance they are, if not faulty, junk.
2. I doubt very much that you're imagining it. At least I hope not.
3. If the pressure is way too high, yes it might force it's way through a vent. Worse, it is quite possible that if your pressure is way too high -- or has been -- that the vents are ruined, even if they were fine when you put them on. Most vents are rated to 3 psi for operation (over that they can be damaged or get stuck) and 10 psi maximum operating pressure (over that, and you need to change them).
4. That's always possible! I keep being surprised...

Perhaps more to the point to your reply, if you don't have main vents -- or if they are too small or stuck -- you are asking your radiator vents to do things they are not meant to do. It is almost impossible to get satisfactory, consistent balance in a one pipe steam system which relies on the radiator vents for main venting. Please look again to see if you can't find them.

paweiss

Well, not from big box, but from my local hardware store. They had $12 ones and $40 ones, and they told me the cheaper ones were fine; they just might not last 20 years. Given that I'd just dropped $230 on a pressuretrol, I decided I'd conserve (read: cheap-out). Maybe wrong decision, but, if I've just destroyed them, maybe the right decision? I will look again for a main vent. But, do either of these bear on whether and why I might be at too high pressure? I'm still concerned that we're running at like 5psi, though it's hard to know really.

Shouldn't I be focused on figuring out if/why I'm running too high pressure? Should I be trying to clean inside the boiler where the pigtail goes in? That's all I can think of right now that might be keeping the pressuretrol from cutting out.

EBEBRATT-Ed

@paweiss
Install a new gage or gages a 30 psi and a 0-5 on the pressure control pigtail. Do that first and then you will know what is going on. Fix the venting and adjust the pressure control based on what the new gauge tells you

pecmsg

paweiss said:

Well, not from big box, but from my local hardware store. They had $12 ones and $40 ones, and they told me the cheaper ones were fine; they just might not last 20 years. Given that I'd just dropped $230 on a pressuretrol, I decided I'd conserve (read: cheap-out). Maybe wrong decision, but, if I've just destroyed them, maybe the right decision? I will look again for a main vent. But, do either of these bear on whether and why I might be at too high pressure? I'm still concerned that we're running at like 5psi, though it's hard to know really.

Shouldn't I be focused on figuring out if/why I'm running too high pressure? Should I be trying to clean inside the boiler where the pigtail goes in? That's all I can think of right now that might be keeping the pressuretrol from cutting out.

Start with Actual pressure readings. Install a 0-5 # gauge along with the required 0-30# gauge!

paweiss

Does this look like the right thing?
https://www.supplyhouse.com/sh/control/product/~product_id=GLP25-5-DS

ethicalpaul

Yes that one should be fine. 0-3psi would be even better

ted_p

EBEBRATT-Ed said:

@paweiss
Install a new gage or gages a 30 psi and a 0-5 on the pressure control pigtail. Do that first and then you will know what is going on. Fix the venting and adjust the pressure control based on what the new gauge tells you

Your existing 0-30psi gauge, sad as it is, should be good enough to satisfy the code requirements, so there's no need to replace it. Save money by just leaving it and add an additional low-pressure (0-3psi or 0-5psi gauge); that's the only one you'll actually use.

Here's one on sale today at SpAmazon:

Low Capsule Pressure Gauge, 0-3 psi,2-1/2" face dial, 1/4" NPT lower mount, Zero Adjustment, Safety Glass Window, blackSteel case

paweiss

Thanks, I'll give it a shot.