Pigtail Clogged?

Fred

As Jamie said Wiring look good. A lot of us use the 0-3 PSI gauge:
http://www.valworx.com/product/low-pressure-gauge-25-0-3-psi

Ransomed_Chicago

Do you use the KC25-3# off Amazon?

JUGHNE

It would be better for all if you referred to the outside numbers on the gauge, the 0-15 ounces, we are mostly old school here and that would put all of us on the same page.

It looks like your gauge has been "punched" by high pressure caused by lack of the vaporstat shutting down the boiler before pegging out the 0-15 oz gauge.
There is a zeroing screw under the plastic cover of the gauge. The cover pops off, you can see some notches under the cover to remove it. This gauge may be beyond resetting to zero as it may be stretched beyond adjustment. I would try it when the boiler pressure is down (cool).

Have you noticed the original 0-30 gauge move during operation? It is on the side of the boiler.

The person who put the vaporstat and low pressure ounces gauge must have know that your system would run on ounces. They believed that your heat would be best operating between 4 & 8 ounces without severe short cycling. They knew something other wise this would have been several hundred dollars wasted.

You may have some venting issues for your returns in addition to the vaporstat and gauge issue.

More pictures of piping might help out.

MilanD

> @Ransomed_Chicago said:
> Do you use the KC25-3# off Amazon?

Yes. Same thing, different manufacturer.

Ransomed_Chicago

Yes, I'll refer to the outside numbers on the gauge from now on (0-15 oz). I tried to reset the gauge to zero tonight; 3 was the best I could do, so I assume I should install a new gauge. I noticed this morning that the gauge still pegged (or possibly just shy of pegging) after the boiler had run pretty much continuously for 30+ minutes.

I found an identical gauge on Amazon for about $45. Unless someone advises otherwise, I'll order the new gauge tomorrow and have it installed by the weekend. Then I would really appreciate some help in fine-tuning the two controls.

In answer to a couple of questions about the piping, etc.:
Yes, there is a gauge that goes directly into the boiler chamber; I never notice any movement on that gauge.
And, yes, there is a temperature set-back during the night (62 degrees down from 68 degrees in the daytime). This accounts for the boiler running for an extended time occasionally in the mornings.
As far as piping, I'm not exactly sure how to describe the configuration, but will give it a shot:
House is 125 year old historic "row house" (meaning it is narrow from the street view, but deep. Two floors (each 1000 square feet) plus a basement (where the boiler is located roughly in the center). There are two piping runs--one goes toward the street about 33 feet. That run serves one radiator on the first floor and two on the second. The other run (about 22 feet) goes from the boiler toward the rear of the house. That run serves one radiator almost directly over the boiler (radiator is on the first floor) plus three radiators on the second floor. There are vents in the basement at the ends of the returns (vents are located very close to the boiler--see photos). I am posting two pix of the two vents on the returns--hope this is helpful to see.

Hope this additional info is helpful. Again, sure have appreciated all the great info!

Abracadabra

I don't see a skim port. I doubt the boiler was skimmed when installed. Might want to think about that.

Ransomed_Chicago

There is a skim port (valve) on the side of the boiler. I do a hot skim and drain off/replace about five gallons of water each weekend, followed by firing the boiler up for at least 10 minutes or so to get O2 out of the new water.

JUGHNE

I would recommend a brass 1/4" ball valve under the new gauge to protect (you would need a 1/4" X 2" long brass nipple also) it if the vaporstat is not operating correctly. Just open it to check operating pressure when you are in the room.

Skimming and also the vents could maybe stand to be increased if those 75's are the only ones on the system.

Abracadabra

Ransomed_Chicago said:

There is a skim port (valve) on the side of the boiler. I do a hot skim and drain off/replace about five gallons of water each weekend, followed by firing the boiler up for at least 10 minutes or so to get O2 out of the new water.

A skim port is different than a drain.
A skim skims water off the surface of the water.
What you are describing is a drain off the bottom of the boiler.
The only thing I see in your pictures that would skim off the top of the water is the relief valve on the left of the boiler. The size of this pipe is not sufficient to properly skim oils off the top of the water.

Also, there is no need to drain 5 gallons. That's too much imho.
If you have a float type LWCO I'd flush maybe 1/2-1 gallon a week.

Ransomed_Chicago

JUGHNE: thanks for the advice on the ball valve--I'll do that.

And Abracadabra: Thanks...I'm pretty sure what I'm calling a skimmer is a skimmer (but, then again, I'm still learning...). Here are two pix: One is what I'm calling the skimmer--comes out of the back side of the boiler, nearer the top. I open the valve when the boiler is up to temp and it flows off a little water (and occasionally I'll see some oily film). The second picture is of the drain (which comes out of the side of the boiler, nearer the bottom), which I open once a week to draw off water (and perhaps, as you note, I'm drawing off too much). Please correct me if I'm wrong about the "skimmer." Thanks.

ChrisJ

Another option to a new gauge is a Dwyer Magnehelic.

Model 2030 goes to 30 inches of water, which is just above 1 pound.

You can often get them on ebay for $20-50 depending on condition etc. Used is often fine.

http://www.ebay.com/itm/Dwyer-Magnehelic-Pressure-Gage-2030-Vintage-gage-is-new-in-the-box-/152051986115?hash=item2367012ec3:g:NPsAAOSwAvJXDVfg


The reason I like the Magnehelic, is not only are they incredibly accurate, they're also robust. The 2030 won't be damaged by anything up to 15 PSI. Even my 2002, which only goes up to 2 inches of water, or 1 ounce can handle 15 PSI without damage. They use a diaphragm who's motion is limited, not a bourdon tube.

The downsides will be it's a 4" gauge, so it's large, which is a good thing but you may have trouble fitting it. Also, you'll need to pickup an 1/8" to 1/4" adapter because the magnehelic is an 1/8" connection.

My 0 - 2" is always on, no protection and no ball valve.

john walsh_2

Maybe I'm missing something here, but why is a vaporstat even needed on this boiler? It seems to me that the pressuretrol on it's lowest setting should have operated this boiler just fine. I'm thinking that the reason that the pressuretrol was causing the guage to peg is because it's a very sensitive guage made for a vaporstat. The only thing that I would add, is that if two pressure control devices are going to be used, they each should have their own pigtail. Because if the pigtail clogs, neither one will work.

Fred

john walsh said:

Maybe I'm missing something here, but why is a vaporstat even needed on this boiler? It seems to me that the pressuretrol on it's lowest setting should have operated this boiler just fine. I'm thinking that the reason that the pressuretrol was causing the guage to peg is because it's a very sensitive guage made for a vaporstat. The only thing that I would add, is that if two pressure control devices are going to be used, they each should have their own pigtail. Because if the pigtail clogs, neither one will work.

He already had the Vaporstat on his system and no reason to take it off, if it works. I don't think anyone said the Pressuretrol wouldn't have worked. I think most of us suggested a 0-3 PSI gauge so he could actually see the system pressure.

john walsh_2

@Fred Got it.Changing the gauge makes a lot of sense.

Ransomed_Chicago

Received the new gauge (0-15 oz scale), cut-off valve, etc. today and installed them. I'll post a full report a bit later, but first a question: I installed the gauge (and cut-off valve)--no issues. When I installed it, I carefully adjusted the needle to zero. I then ran the boiler for most of an hour (full report on that later). After the boiler cooled down, I noticed that the needle on the gauge is no longer at zero, but rather below the zero mark by an ounce or so. I'm guessing there is a vacuum of some sort (maybe created by the pigtail cooling down??). So should I re-zero the gauge now that it is installed OR just leave it alone (thus relying on the zero adjustment I made when I took it out of the box). Hope this makes sense.

ChrisJ

Yep, that's caused by the pigtail.
That's why I stopped using a pigtail on my low pressure stuff. Just an 18" vertical length of pipe to make an air trap.

I still have my code required Pressuretrol and 30 PSIG gauge on a pigtail of course.


DO NOT keep re-zeroing the gauge, it will keep happening and at one point you'll damage the gauge.

Fred

You will find that it will zero itself out again before the next heat cycle. It measures pressure and when there is a little negative pressure, be it system wide or as Chris suggests, maybe between the water in the pigtail loop and the gauge, it will show on the gauge but it zero's as the vacuum breaks/system pressure normalizes.

Ransomed_Chicago

OK...good to know; happy I asked.

So, here's the update on the system after installing the new gauge. I turned the thermostat up to 75 degrees so it would be calling for heat continuously; I started timing cycles. The boiler went through three cycles of running for about 14 minutes continuously with a one minute break between cycles. During that entire 45 minutes or so, the pressure was between zero and .5 oz. Then the fourth cycle started and the pressure gauge started rising steadily over the next eight minutes; the boiler cut off at 13.5 oz after running continuously during that time. During the following one minute break, the pressure went down to about 6 oz. The boiler cut on again and within about three minutes, the pressure was back up to 13.5 oz at which time the boiler shut off again. I let it run thru three more such cycles (all about three minutes each---running up to 13.5 oz, shutting down for a minute at about 6 oz and then cutting on again). Here is a picture of the Pressuretrol, the v-stat and the gauge (there is a ball cut-off valve under the gauge; the vertical handle is hidden in the camera angle).

So is what I described above what I should expect? Or do you recommend adjustments to the Pressuretrol and/or v-stat settings? I realize that the "test" I did would be more like the initial start up on a cold morning after the thermostat had set-back for the night.

Thanks again for all the good advice!

Fred

Do you have a Cyclegard Low water cut-off on that boiler? It sounds like the first 14 minute cycles were cut off on maybe a low water check. The cycles that were 3 minutes each were what is known as short cycles that occur when the boiler is run for an extended heating cycle and is too large for the connected radiation or possibly a lack of adequate main venting. In any case, the cut-in and Cut-out pressures are good and I wouldn't try to adjust either the Pressuretrol or the Vaporstat any. Actually, the Vaporstat is controlling the pressure, which is as it should be. The Pressuretrol is a back-up at this point and won't do anything unless the Vaporstat fails.

Ransomed_Chicago

Yes, there is a Cyclegard LWCO. So sounds like the system is running as should be expected. The Wall is a great resource for DIY types like me; you guys have been very forthcoming with good advice. Much appreciated!

Fred

It is running as it should. If you ever decide to change that Cyclegard out, use a Safegard Low water cut off. It does not stop the boiler to check the water level. It uses the same probe as the Cyclegard so the probe doesn't have to be changed.