Pressuretrols set correctly?

Coffeecup

1st time home-owner trying to get my head around our one-pipe steam system. Been reading for hours but I am a total noob. I'm wondering if it's possible to tell if these Pressuretrols are set correctly / reasonably correctly? Not quite sure how to read them, these so pictures attached.

Also that Weiss gauge never seems to move - according to some in the building - "it takes hours to move" - the gauge is marked PSIG - is this normal, at what point should I be checking it, what should I be looking for. The system comprises Rockmills MP-30 boiler with Carlin 701 CRD burner.

Thank you so much for any help.

Fred

I'm assumming this boiler has a 2 stage burner (or gas valve) on it, hence 2 of the Pressuretrols. They look like they are set fairly well. The third one (with the red button on it) is a manual reset. If it were me, I'd set that one at about 5 PSIG. There is no reason to let it get up to 10 PSI before it trips.
I'd also get a 0-3PSI gauge and put on the boiler. You can Tee it off of any of those pigtails (looped pipes) to protect it from the steam. Leave the old 0-30PSI gauge on there as it is required by code but they simply do not measure low pressure steam well. The goal is to keep the steam pressure down as low as possible, max around 1.5PSI at most during a heating cycle.

Coffeecup

Thank you! Yes it has a two stage burner (oil). Makes total sense to me to add on a more sensitive gauge. Thanks again.

Steamhead

This must be a good-size building, with a boiler like that..... where are you located?

Coffeecup

Harlem. Boiler runs two 5 unit buildings. That said, EDR is 2,300 sq. ft, boiler puts out 4,185. Nevermind that in my first winter there I discovered that we were paying way too much money, for way too little heat, the place was chilly and the fuel bill was ridiculous. Mr. Cataneo took care of the "not enough heat" problem, thank you John for the outstanding venting if you're reading this. We now have too much heat, folks are opening their windows.

I think the prob is with our Heat-Timer (MPC Platinum which seems way off. Bear in mind I am clueless about all this, but nevertheless I watched it today from a cold start. The set point is 175 deg (don't ask, it's historical), but the system temp never achieved more than 171, (at least when I left after about 15 mins of it never getting above 171, which it took about 40 minutes to reach). I assume from this that the set point must be wrong, that the system doesn't cycle correctly, causing the overheating. Is this a fair line of logic to follow or am I way off-base. Still have to determine the actual set-point which hoping to do this week by measuring off last radiator in top flr apt. Then the next trick is going to be getting the keys to the panel. Co-op living not always fun.

Steamhead

That 175° setting is likely for the "steam established" sensor, which tells the Heat-Timer to start its countdown to the point where it shuts off the burner. The length of the countdown varies with the outdoor temperature. We generally use Tekmar controls, but the principle is the same.

I have a hunch this sensor is not located in the proper place. We get good results by placing it where it will pick up the sudden temperature increase when the steam reaches the piping just before the furthest radiator. Then, the countdown occurs as the radiator is heating up. Waiting to start the countdown until the radiators are completely full of steam often leads to overheating, especially in milder weather.

The best place for this sensor is at the top of the riser feeding that last radiator. But the riser MUST have a vent so it will heat up even if the radiator is turned off. If riser mounting is not practical, the next best location is at the end of the longest steam main.

For this to work well, the steam mains must be well vented so the system can respond quickly. But it sounds like one of our fellow Wallies has taken care of that.

Coffeecup

OK, thank you we must be way off. That burner hadn't turned off when I left the basement after over an hour (unless the loud "working" noise I hear in the boileroom is not the burner working) , and when I got to my apt a minute later all the radiators were fully heated up. So if I understand correctly that burner should have shut off way before that.

That sensor is located just outside the boiler room - I think it's on a return pipe. This was done some years ago and apparently it was "not possible" to put it on the last radiator, but ymmv. Mains and risers all properly vented now. As John explained this is a step by step process. You guys have created an amazing place. Thank you.

Steamhead

Coffeecup said:

That sensor is located just outside the boiler room - I think it's on a return pipe. This was done some years ago and apparently it was "not possible" to put it on the last radiator, but ymmv.

Aha- it probably takes forever and a day for the heat to reach that point. Fortunately it's easy to change this- all you need is enough shielded cable to go the distance. Try the end of the longest steam main, just before the main vent.

You will probably have to completely recalibrate the Heat-Timer after moving the sensor, but it should work a whole lot better when you're done.

John & Co. would be able to handle this.

Coffeecup said:

You guys have created an amazing place. Thank you.

You're welcome, from all of us. Let us know how you make out.

Coffeecup

Well I did not make out too well. Truth be told I'm completely bewildered. The set point had been set at 175 and my apt was cooking - all radiators, completely hot, place was way too hot. This a 5 story apt building. I am on the second floor. Everybody was complaining of too much heat.

We shut off the boiler for 3 hours and then fired it up on bypass with "heat established" point at 249 deg. The 5th floor apt reported last radiator starting to get hot at 171 deg. So we set "heat established" to 171 deg, and the cycle length to F, which should have given us 7 minutes of heat on a 40 deg OD temp. The guy on top floor was happy with the result, but as for me on the 2nd flr, hardly any heat on the rads that normally heat up first (south side), absolutely none on the others (north side of apt). Even the pipe bringing in the steam on these cold rads, did not get hot. We left it like that for a few cycles, and nothing changed. So we went to 172 deg set point - b/c the system temp takes 6 minutes to move from 171 to 172, and then it stays on 172 for another 6 minutes, until the cycle kicks in, which would have given 5 minutes of heat at todays temp. So we figured that's another 17 minutes of steam - but the reslut was the same - every apt above mine started heating but my rads and pipes going into them, remained cold. The risers heated up fast and were full of steam all this time, but my North side rads remained cold, my south side did not get as hot as they used to.

So we put the system back on bypass and gave ourselves two full hours of steam - still nothing in my rads, the pipes bringing the steam into them - one was hot but nothing in rad, the other was barely warm - and this is a rad next to a riser that was hot the entire time.

I am at a complete loss as to how come I was cooking at 175 set point, moved it to 171 etc, lost heat in my rads while the apts above mine are heating up adequately yet. Cannot get steam back into those rads no matter how long the system runs for - it must be going somewhere - just can't figure out why, how, where.

Unfortunately we have not had access to the apt below mine, so no idea what's going on there. As for piping diagram, I'm going to have to try find the orig building plans at NYC DOB. This building was built in approv 1896.

I made some notes regarding system time and temp and have attached them, not sure if useful or not. We have some issues with "heat established" sensor not being correctly located, but I am completely mystified how my apt went from "cooking", to cold radiators, no matter what we did, as described above. NYC did suddenly warm up this weekend, and for ex today was 45-49 deg, (it was in the 20's when my place was overheating), so not expecting to get much heat - but as of now the folks above me are getting steam in their north side radiators, and I have nothing, their south side rads are well heated, I have 1 hot fin on one of them and nothing in the other (and these are normally the first to heat up). This anomaly happened before when we had shut things down for a few hours, but we were mid winter at that point, with very cold days and too high a set point and after a day and a half or so I had my steam back.

As of now, while everyone else is reasonably satisfied, it does not look like any steam intends coming into my apt. Any ideas what on earth it could be thinking?

Thanks.

Fred

How many radiators in your apartment? Based on what you are saying, it almost sounds like the vents on your radiators are either stuck closed or have some condensation in them. When the boiler is not running, take a vent off and hold it upright and see if you can blow through it. Also shake it out and see if water comes out of it. If you can blow through it and you have shaken the water out, put it back on and see if you get heat on the next cycle. If you do, you may need to soak those vents in vinegar to clean them or, if they are really old, it might be a good idea to replace them.

Coffeecup

Six radiators. I have taken off all the vents and one of them had some water which surprised me (never seen that before). I shook it out then blew through. All the others blew through fine.

Fred

Are all the supply valves open and are the radiators all pitched back towards the steam supply pipe? The only reason your radiators aren't getting hot, when all around you are is because something (air) can't be expelled through the vents or something (water) is causing the steam to condense before it can fill the radiator.

Coffeecup

Yes, this is why it's such a mystery - everything was all working perfectly, except for the excess heat. All supply valves are open (and new), radiators all pitched properly, double-checked. The only thing I haven't checked was to see if the super in basement apt, did anything in his apt that could affect us? When I wasn't getting steam, I pulled off one of the vents while cycle was on - air coming out did not seem steady, seemed to come in pulses?

Fred

Pulsing air may mean water being pushed to and fro by the steam which probably is condensing before it gets to the radiator. Of those six radiators, how many of them are tied into a common horizontal feed pipe? It would be highly unlikely that the pipe that feed all those radiators have settled but you might try a couple things, first, if you can determine which line, in the basement feeds your riser, check to see if it is pitched back towards the Main. if not, or if that pipe has a sag in it, that pipe may have water setting in it limiting the amount of steam that gets to the rads on that riser.
If it looks like it is pitched ok and has no sag, see if you can raise one of your radiators, at the supply end maybe a quarter to a half inch and then repitch the radiator. Sometimes a horizontal, under the floor will lose its pitch.

Coffeecup

The 2 radiators on south side are on one horizontal, then on the long supply line that runs south to north, the 2 rads in the middle of apt, branch off, then the 2 on the north side of apt are at the end of the main feed pipe. There is no noise from the system at all, I am seemingly the only one affected - the steam just seems to pass by the apt.

The radiators at north and south ends feed off the adjacent risers (few inches away), which get very hot. Floorplan attached.

We have checked the pitch on main lines and returns, recently had a section of sagging return replaced after it was checked out. (this was done at the time the system was vented properly). Yesterday, we discovered a leak in the return piping on the floor of the basement, where there is a shut-off. It seemed to be a new leak. Our super will replace the shut-off.

JUGHNE

In your picture with the leaky valve, what is the function of the check valve in the smaller pipe ?

Fred

The only other thing I can see happening is that other radiators on those risers, probably above you are vents with large vents and, as you know, steam takes the path of least resistance. They may be getting all the steam because they vent very quickly and the boiler timer times out before it runs long enough to finally get to yours. You need to see what the radiators in the apartment below you are doing.

Coffeecup

Jughne....that I'm afraid is above my pay grade. Perhaps you can tell from this picture - it's by the white pipe on the floor sort of near the middle of the picture.

Coffeecup

Fred, yes, I need to see below, will make those arrangements, unfortunately may take some time due to that owner's circumstances. Thank you. David.

JUGHNE

I think that is part of the cold water fill into the condensate return from the LWCO auto fill now that you posted that picture.

Fred

Coffeecup said:

Jughne....that I'm afraid is above my pay grade. Perhaps you can tell from this picture - it's by the white pipe on the floor sort of near the middle of the picture.

I'm not sure about this one but I have a similar one on the water supply that goes into my wet return. It actually is suppose to serve as an early backflow preventer. Has a one way swing gate inside it.

Coffeecup

Fred, thinking about what you said, about those above me venting too fast. I think it may be a factor. It wouldn't surprise me if folks above me have bigger vents on the higher floors. Now that the system is properly vented, that may no longer be appropriate.

Fred

Coffeecup said:

Fred, thinking about what you said, about those above me venting too fast. I think it may be a factor. It wouldn't surprise me if folks above me have bigger vents on the higher floors. Now that the system is properly vented, that may no longer be appropriate.

Yep, that's why it is so important to fix the main venting first and then move to the radiator vents. Most of those radiators probably have large vents on them to make up for the fact they had to move air from the mains as well. If they are adjustable vents, it may be a relatively easy adjustment. if not, new vents may be required or maybe you could try a large vent on a couple of your rads.

Coffeecup

I can blow some cash on larger vents and not bother anybody, or I can get the entire building to change all their vents, likely a protracted negotiation. At the moment I have Maid-o-Mist "Jacobus" 5's and 6's, would D's be overkill - how do you know if it's too big - any downside to a radiator vent that is too big, except I suppose to prevent my downstairs neighbor from getting any heat!

Abracadabra

What type radiator vents are on the "too hot" apartments?

Coffeecup

Not sure, have to find out what they have.

Fred

Coffeecup said:

I can blow some cash on larger vents and not bother anybody, or I can get the entire building to change all their vents, likely a protracted negotiation. At the moment I have Maid-o-Mist "Jacobus" 5's and 6's, would D's be overkill - how do you know if it's too big - any downside to a radiator vent that is too big, except I suppose to prevent my downstairs neighbor from getting any heat!

The correct way to vent is to vent Mains fast and radiators slow. There re issues with venting radiators to fast. Rooms, other than where a tstat might be located can get too hot, radiator vents can get condensation in them and not work, very fast venting radiators can rob others as steam will take the path of least resistance.
The right thing to do is balance each radiator based on radiator size and distance from boiler, assuming the mains have all the venting they need.
My suggestion to you is (since we don't know for sure that radiator venting is the underlying issue) put a large vent on 1 or 2 of your radiators to see if that gets steam to those radiators. If it does, then you know the other apartments are probably the path of least resistance and are over vented due to the history of the building not having adequate main venting until recently.

Coffeecup

Thank you Fred, I think now with proper venting a lot of the old set up needs to be reconsidered. Since it's warm outside, for now the risers alone are enough to heat the lower apts to a comfortable temp. However the top floor is still experiencing piping hot radiators - have not yet managed to discern what valves are on there - folks can be slow to relay info - but I know in the past when it was too hot up there they would close the valves to shut off radiators. Is this ok to do - is there a right and wrong way to go about it - eg only close the valve when the radiator has cooled down completely.

As a test before I buy new vents, am thinking of asking him to close his radiators completely and see what effect it has down below. I think our system is now vented so well that he would be happy to switch off a radiator or two, so wondering if that might solve the prob. Any thoughts on that approach. Thanks.

Fred

Actually the best way to shut a radiator off is to turn the vent upside down so that air can't escape. More often than not, with old valves, they don't always seal properly and steam still seeps into the radiator but condensation can't flow back out and you start getting some water hammer at the radiator.
It is best to do that when the boiler is not running, more for safety sake than anything else.
Are there any vents at the top of any common risers that feed all the floors? If there are, another option is to put smaller vents on those risers to the apartments that overheat .

Coffeecup

Ah, thank you that makes so much sense. There is only one vented riser in that top flr apt - I will touch base with the owner to find out exactly where it is, and will take things from there. Thanks again for all your help.

Don_197

CoOps can be so much fun (NOT!!) I took care of one here where the "super" would go and turn off heat to people he was mad at.......we eventually replaced the boiler.........had to go to several CoOp meetings to explain the process, benefits, etc. Then coordianting to get into each apartment was REALLY fun.......CoOps......a never ending adventure. One thing is though......most of the ones I have been exposed to were absolutely beautiful turn of the century buildings.....with the historical heating systems that we would never get to see otherwise.

Coffeecup

Hi Don, yeah it's a beautiful old building and the apts are great but the coordination can be tricky. Reason and logic seem to disappear at critical moments. But there are a few of us who are determined to get things ship-shape. We're in it for the long haul so it's ok. Never dreamed I would become so fascinated with steam, but there's definite satisfaction in learning how it works.