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Desperate for Help Troubleshooting

ItsFixableItsFixable Member Posts: 5
Hello All,

I am a homeowner, trying to educate myself on my system to find someone to help me fix an issue with my heating system. I have a Weil-McLain boiler that is about 24-25 years old, on a monoflo heating system. I had an additional heating loop installed just over 3 years ago to heat an addition that is on piers. At the time, I had 3 plumbers tell me that I could mix fin convectors with baseboard heating, 1 had one older plumber tell me not to do it. I went with one of the three, against my better judgment. Since then, I have been having a lot of air get into the system. I have been reading on and off since then, trying to educate myself, and at one point someone said it took them a good year to get all the air out of their system after some work they had done. I became very diligent with bleeding the convectors last year and only found the first convector closest to the boiler had air in it. In addition, since having all this done, one convector sounds rather noisy, at the far end of the house, but no air, maybe it is just the pipes moving at this point, I don't know. Anyway, I thought I had all the air of the system and now we start all over again. As I have been paying more attention to it, I noticed that it doesn't always happen. And I don't necessarily get any air out of that one convector, but I will either hear gurgling in the boiler or a slushing noise in the area. Again, this does not happen all the time but it happens. The heating system is working, everything gets warm but the noises are beginning to drive me crazy. In addition, I have learned enough to know that continuous bleeding is not a good thing and one should not hear the gurgling or slushing noises. Today I have decided to pay attention and make a log and see if it is more obvious on colder days or if there is any pattern to it. This morning after the system ran for a while since it was a colder morning when it shut down it made the gurgling sound.
Also, there is a swetcheck valve that has been chattering for the longest time, I was told that was okay, but it has since stopped in the past few days for whatever reason. I am not sure what that means or if it is even related.

One thing I was wondering is that I noticed the water coming back into the system, when the heat turns on, from the slab area is very cold compared to the water from the rest of the house. The other thing that I have learned is that the amount of baseboard I have in the addition is really too little, underheated, and thus the room gets very cold very quickly and thus the reason for the water in those pipes to get very cold. I am wondering if this could be a source of a problem for the system since very cold water meets warm/hot water and could cause air in the system.

Lastly, I am not sure what to make of it, but the pressure appears to be okay, I have the local gas company service it but they don't deal with my kind of slushing issue, because according to them it is working and I have been told to just bleed the air out. The pressure when heating is 20 psi.

I know this is very long but I am kind of at my wit's end with the noise and I really want to know what I am talking about when I have someone come out and have a look at the system.

I have attached some images of the system. I do have a second zone on the system, the second picture, that I don't use. It is for the finished basement but I don't heat down there. The last image is showing where the new heating loop was installed.

I know this is very long, but the noise is really driving me insane and at least from what I have read, it is not healthy for the heating system.

Thank you so much for your help and patience with this posting.


  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,994
    All you need is a service tech with a brain. Without seeing the job it's hard to tell what is wrong but it sure sounds like an air issue.

    I would suggest trying "find a contractor" on this site.

    Where are you located?

    If no one on this site is in your area someone may be able to make a recomedation.
  • ItsFixableItsFixable Member Posts: 5
    Thanks so much for getting back to me. I am in the Hartford area of Connecticut. There doesn't seem to be anyone from Connecticut in this forum. Any suggestions would be welcome.
  • Jamie HallJamie Hall Member Posts: 14,797
    Try @Charlie from wmass or @dobro23 . Charles is in Springfield, but works in Connecticut, and Dobro is in Danbury. Both good -- and both very busy.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.
    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • ItsFixableItsFixable Member Posts: 5
    Thank you so much!!
  • IronmanIronman Member Posts: 6,142
    edited January 10
    One of the problems is that the new loop should not have been tapped of the monoflo loop. That needs to be redone with its own loop, circulator and thermostat.

    Another issue appears to be that the circulators are pumping in the return and probably towards the Point Of No Pressure Change, which is the point where the expansion tank connects to the system. They should be "pumping away" from the PONPC. A lot of systems are set up like yours and get by with it, but it's not correct and can cause issues. The pressure at the farthest part of your system will be about 10 psi less with the way it now is. That can account for air in the system since it's not easily removed at low pressures.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • ItsFixableItsFixable Member Posts: 5
    Wow, thanks so much for your input. Can you explain why it should not be tapped off the monoflo loop?
    Also, yes, I have heard about the set up from one of the gas guys that came out, but he said it would be $$ to fix it at this point and better to do so when the system gets replaced based on the age of it.
  • IronmanIronman Member Posts: 6,142
    The monoflo loop has a different "head" (resistance to flow) than a series baseboard loop.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • HomerJSmithHomerJSmith Member Posts: 1,073
    edited January 11
    I'm not sure what you mean by "fin convectors". Are we talking about toe kick convectors with a fan?

    I had a job where there was a baseboard loop and on the remodel I put in 2 Runtel flat plate wall radiators, 2 under cabinet toe kick heaters, and a small injection pex loop, all in an existing baseboard loop. I used real monoflo tees for the Runtels and toe kick heaters. I don't use cheap diverter tees. I also put coin vents on the toe kick heaters because the supply was from under floor. Worked just fine. I also had to put a booster pump on that loop, the longest loop in a 3 story house, because the ECM pump didn't have enough poop to give me the 3 gal/min that I wanted.

    It's all in how you do it.

    Pics of the "fin convectors" and the monoflo tees would be helpful.
  • HomerJSmithHomerJSmith Member Posts: 1,073
    edited January 11
    I'm not a fan of baseboard monoflo sys. Ya, they can work and again it can be marginal.

    I replaced an oil boiler with a nat gas unit in a monoflo sys. The owner told me for the last 9 years he was freezing. The drapes on his window were a 1/2" thick. I removed all the monoflo tees and re-piped the baseboard loops in series. The owner said that he was so warm that he had to open the windows, well almost. I suspect that he had a flow problem. Flow is the conveyor belt that moves heat energy. Perhaps, a higher head pump would have solved the problem. Do you think a higher head pump would solve your problem, as Ironman says?
  • ItsFixableItsFixable Member Posts: 5
    Thanks so much for your input. I apologize in advance if I don't supply the proper images as I am not sure of the correct terminology and what you might be looking for. One of the images above shows the connection going to the newer baseboard loop. The first t-connector is the supply side and the second is the return. Below see an original example of a t-valve going to a convector. I have convectors through the house with, a monoflo system. It is only the addition that has a baseboard. The house is small, only 1000 square ft and over 60 years. My heat has been fine until this loop was put in.

    Thanks again!

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