Indirect HW off steam- shaking circulator

hot_rod

While not a cheap date, this type of circulator, a B&G PL series, would keep the motor out of any dirty water. This is an air cooled motor as opposed to a wet rotor design., 225°f rated

The B&G series 100 is another option.

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EBEBRATT-Ed

If I am not mistaken the bypass loop Dan talks about is to keep a HW baseboard loop from overheating and to keep it at a reasonable temperature.

A hot water loop to an indirect probably does not need a bypass loop as the circulator starts and stops on the tank temperature sensor

ethicalpaul

Thanks @EBEBRATT-Ed and @STEAM DOCTOR I appreciate the correction!

WilliamME

I appreciate everyone's input here, the wealth of knowledge is amazing.

While not ideal, the company is going to start by returning Wednesday to re-pipe according to the diagram in the owner's manual. As all of you agree this will likely not correct the issue, it perhaps may even make it worse. Their plan is to consult the manufacturer if the prescribed installation remains problematic, then take instructions from them how to remedy from there. While this method is inconvenient for the company, and for me, I suppose it's not as bad as a scenario where they deny there is an issue. Perhaps, it may eventually result in them installing it in a fashion resembling the preferred method.

I'm not the most assertive when it comes to trying to influence the methods chosen by installers who admittedly know more than me, even if I have access to you all here who seem to know more than them. Furthermore, despite the headaches of this install, I do believe I was given a very fair contract price, and they have not issued any change orders throughout the process. I will be posting their progress on this issue as soon I can. I could see a point where I may just give up if its drags on too long without resolution, and try my own hand at it using the knowledge conveyed to me here.

@EdTheHeaterMan , thank you for suggestion about flipping the circulator and opening the flochek; however at this time I am hesitant to interfere with their installation until they are done attempting to fix it themselves.

@STEAM DOCTOR I will need to double check the model number on my indirect, but I believe it is a Crown MT040GBR 

As a fun aside, for my own work (I'm an electrician), the customer I have started working for has a massive 1-pipe steam boiler, I took a moment to quickly examine their setup for the indirect HW and noticed they have the heat exchanger and double circulator configuration from the document @ethicalpaul linked me to. Very cool to see! I was curious what this black sphere object was though. I can delete these images if they're not relevant enough to the thread.

EBEBRATT-Ed

McDonnell Miller Low water cut off and automatic water feeder. #42

WilliamME

https://forum.heatinghelp.com/discussion/comment/1840043#Comment_1840043

Thanks 😃

hot_rod

I think the two pumps is when you use a storage tank without a coil. The black pump moves flow through the external plate heat exchanger and the tank.

Hope he catches a mouse😉

WilliamME

Re-piped. Pulling water from the top of the boiler and pumping it down to the bottom as before, except this time the circulator is up high, and the water connections are all on the back of the boiler, instead of from back to front of boiler.

Rather faithful to the instruction manual diagram this time around, except the supply pipe is not going low to the floor first, it's going straight over to it. I asked about that and he said he can't do that because it would cause a sediment trap. He said my water tank would need to be lower than it is in order to pipe it precisely to the manual. I don't understand how the manual would expect this of a typical installation (because despite the fact that, yes- my water heater is on a raised platform) the bottom is still the same level as the boiler which is also on blocks. You would almost need to dig a pit to put the water heater in order to meet their design, but this also isn't the same indirect water heater referenced in the manual so that may be the problem.

It's been a week, I haven't noticed it knocking or making noise anymore, but keeping an eye on it. Incidentally, my re-pipe came with a strainer fitting.

ethicalpaul

This guy really likes to ignore the instruction manual. (I'm speaking of the height of the circulator). Oppositional Defiance Disorder perhaps.

How high is that port compared to the normal water line? It seems very high.

WilliamME

The tapping he used is the tapping specified by the manual to use. I skimmed the boiler several times myself after it was installed, as they only did it for 30 minutes and I didn't think that was sufficient. All told over 2 months it's probably been skimmed for 4 hours collectively. They have also fully drained the boiler twice in those two months. I guess I didn't tell them I've been skimming, because I didn't want them to get upset I was tinkering with their install, but I felt like it needed it.

During skimming I had the manual feed cracked just a hair to get a flow "no more than the size of a pencil" according to the manual. Once I was done skimming, I would turn off the manual feed and leave the skim port open until it stopped dripping. This corresponded with about 1/2 way up the gauge glass, and I estimate that to be about 4" above the tapping they use for the hot water. That being said, each time they come to service the boiler they set they water level lower than I do, about 1/4 up the gauge glass, which corresponds with about 2" above the hot water tapping.

The first time they left my boiler wasn't firing with a call for heat, and upon observation the red LED on the LWCO was flashing, so I added more water (slowly) to get it back where I had it before. I made the mistake of mentioning that to the installer upon their return, and he sort of snapped at me for not letting the LWCO feed on it's own. I suppose he had a point, but it had been about 15 minutes with it not firing or auto feeding, was that too soon to manually intervene? Anyways, I haven't skimmed or touched the water level again this time around, it's been set by them against to be at about a 1/4 up the glass.

Having said all this, I don't think either of us of have set the water level to manufacturer spec, I will have to look again, it's something like 27 1/2" off the floor or something (I really ought to check that spec, irresponsible, I know). I think both of us are guessing at the normal waterline.

WilliamME

So, with the pump up top, less gravity, the water is under the least amount of pressure it could be under while being pumped- but apparently this works better than it trying to pump down low from the top of the boiler while it was located far away from it's supply.

Without symptoms of things going wrong, I probably can't get them to change it anymore. If it's not cavitating do I need to worry? My only thought its where they like to leave the water level lower than I was putting it, problems may arise if the system loses water. Without the help of gravity, is the immediate implication the circulator works harder, uses more energy and wears out faster? Should I also expect the recovery time the water heater needs will now be longer (I haven't been able notice a difference so far)?

I will either fix it myself or pay someone to fix it in the future if you all think its daft to leave it this way long term, but right now I have some fatigue over this project since it's been ongoing since early November.

My plan would be to buy a nicer brass circulator, move it down low again, remove the flo-chek, but reverse the flow to pump from bottom of boiler. This- as I have come to understand, is the prevailing wisdom I have received.

ethicalpaul

I sure wouldn’t buy a brass one until this one fails. If you increase the ph your water will stay very clean.

WilliamME

https://forum.heatinghelp.com/discussion/comment/1842444#Comment_1842444

I saw in your video that you have a clear fitting in your piping, where I could see the water was pink/purple. Are you using the 8-way treatment for ph? That may in fact be something I would like to add in the near future. I'm assuming I would need to buy some litmus papers first. What is an ideal steam boiler ph?

Somewhat unrelated, and probably better asked in a separate thread- I was also thinking about raising the water level to the risers in the summer when the boiler is not making steam to lessen the chance of waterline rot. But I was worried that adding the make-up water in the summer would cause corrosion. The aqua stat for the water heater is only 185 degrees, is that high enough to drive oxygen out of the water? I am assuming it would not be. Other thoughts I had was trying to see if after I filled it if it was possible to let it try to boil the water with no steam chest left, but I feel like that would be bad for it, or would trigger the pressuretrol. What about skimming some boiler water now during the heating season, topping back off, then storing what I drained to use as summer top-off water?

ethicalpaul

Yes I use 8-way. You can get indicator strips from amazon for cheap, they have them that cover the target range for boilers which is 8-10 or so. But you don't really need them because 8-way is a pH buffer that pretty much puts your pH at the right place. It has an indicator color in it to show you the pH is OK. Just use less than they recommend and only add it to clean water. Then after that, work to minimize how much fresh water you add. Don't drain just for fun or periodically for no reason and the water will stay very clean.

Now, your other question. Here is where you will hear my very most current thinking on this that lots of people will probably disagree with, which is fine, skepticism is the basis of science.

I think you are smart to fear the addition of water for the off-season. And I think the temperature doesn't matter (although I do think 185 is hot enough to drive out the oxygen). But I think the idea of "driving out the oxygen" doesn't matter. Once you introduce fresh water, boiling out the oxygen does happen, but then the oxygen is inside the boiler cavity and it oxidizes the iron. This is why I think we always see boilers rotting out at the top of the castings. There is also corrosion at the water line, it's true, but I think the boilers that fail at the top far outnumber the ones that fail at the waterline, if any do.

I do think it's good to vary the waterline but I think the best way to do that is to let the waterline vary during the heating season, then leave the water wherever it is at the end of the season until spring. So during the winter let it get a little low, then refill it pretty high, and repeat so the level is moving during the heating season.

Don't let the auto-filler fill it for you, I think that lets the water level get too low. You want the water level higher than that so that the upper castings don't get overheated from being dry from low water line. And especially in your case you want a high waterline due to where your supply tapping is for your circulator.

Your plan to store the old boiler water isn't crazy. But I don't think you have to do that. If you want to really do the thing to make your boiler last, you can just add pre-boiled water to it. And if the water is distilled, all the better to eliminate dissolved solids and chemicals like chlorine. Then you'll be as over-the-top as I am.

If you don't want to do all that, you can use regular water for make-up water, just always work hard to minimize it.

WilliamME

Thank you @ethicalpaul for your continued helpful guidance. I like being over the top! I've subscribed to your YouTube channel, I'm interested in learning more from you.

I will plan on adding the 8-way in the near future. Maintaining this boiler is incredibly important to me because it's been a huge investment having it replaced. My previous boiler succumbed to a hole in a section, unfortunately it came that way when I bought my home and I didn't know it. The rust was so bad I couldn't tell if it was waterline or top of casting.

I like your idea of varying the waterline by starting the season with a high water level and letting it naturally go down (although so far my water level doesn't seem to budge much.) I'm probably overdoing it imagining filling it. In terms of that idea, my hope was that the oxygen would be pushed into the risers instead of staying in the boiler, and the risers would be sacrificial and offer less surface area for oxygen to be absorbed.

In terms of adding distilled water I didn't know I could do that, I imagined that might be problematic, but I had no real basis for this notion. I feel like I read once that if distilled water isn't stored properly it absorbs carbon dioxide from the air and creates carbonic acid, but I never looked up if it was bad or not to put it in a boiler. Would you need to boil distilled water or has distillation ensured no oxygen content? I wasn't sure if it gets re-oxygenated being bottled at the factory.

ethicalpaul

I don’t buy it from the factory, I collect it from my dehumidifier.

I’m sure it collects some gases in storage but it’s surely less oxygen (or no more) than what comes from the municipality where they often pump oxygen into it.

Over a winter you might have to add roughly a gallon a month. Any less than that and you’re doing great and should get a long service life from it

Forget carbonic acid, every time your boiler runs you are injecting distilled water into it, and what can you do about that?

Long Beach Ed

Mattmia's on target with this. You can't run 210-degree water through a pump. When the boiler is steaming, the water is that hot. It will flash to steam when it hits the reduced pressure in the pump. That's what you hear. It will destroy your pump.

You need a bypass with a globe valve so you can throttle the temperature by mixing in some recirculated water. By doing this, you lower the maximum water temperature.

Your aquastat only sets the minimum boiler temperature.

And good practice pipes that pump on a steel pipe.