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New Installation Questions

corey_scorey_s Posts: 17Member
edited June 18 in THE MAIN WALL
I just had a new boiler installed. I have a couple of concerns I wanted to ask about on here before having the installer convince me everything was done correctly.

First, the electrician put conduit against the smoke pipe. I think this could melt the insulation on the wires inside? Next, the bypass is installed a little differently than what the manufacturer documents show. shouldn't there be another valve after the bypass and just before the return water enters the boiler? My last concern is that they crimped on the bigger diameter pipes from the new boiler to the smaller pipes from the old boiler just before it goes into the iron pipes from the old gravity system. Shouldn't the copper pipes from the new system be connected directly to the large iron pipes with out having three different size pipes?

I'm not sure how big an issue these things are, or hopefully there is no issue and I'm just worried for no reason because I don't completely understand all of this. After spending so much money I really want to be sure we have a good system that will reliably last for many years. I'd really appreciate opinions on this. Thanks so much.


  • STEVEusaPASTEVEusaPA Posts: 3,149Member
    edited June 18
    It's ok-ISH.

    Looks like the circulator is upside down, can't tell for sure. Also can't tell if your pumping away from expansion tank.
    Bypass valve is ok, but probably pricey. If I had to use a valve I would've a globe valve. But I almost always use a thermostatic mixing valve.

    As far as the piping, small to large, that's pretty standard when replacing a big gravity beast. Looks like they were already reduced based on the small piece of copper to the new crimp connection. Without knowing how many btu's are required for each run out, can't say for sure.

    Would've liked to see a Webstone Expansion Tank Valve on the expansion tank and the tank strapped/supported to the wall.

    Conduit shouldn't touch the smoke pipe. Don't think your flue temp will get hot enough, but why risk it. Installer could make a simple offset with an elbow on the flue, or an offset or move the conduit over a little.
  • JohnNYJohnNY Posts: 2,317Member
    You're going to have trouble balancing that system through the two different runs, even with the ball valves in place. Your pump is very small for all the water in those large-diameter pipes so I'm guessing you'll see some short cycling right away. It's basically what you'd expect from an HVAC company.
    A proper plumber/boiler tech would've created a primary secondary loop system and dealt with the two vastly different flow rates (through the boiler and piping system) individually.
    For installations, troubleshooting, and private consulting services, find John "JohnNY" Cataneo here at :
    "72°F Mechanical, LLC"
    Or email John at [email protected]
    John is a professional Master Plumber, licensed by The Department of Buildings of The City of New York, and works extensively in NYC while consulting for clients in and out of state.
  • Steve MinnichSteve Minnich Posts: 2,467Member
    @JohnNY "A proper plumber/boiler tech would've created". Plumbers are different in different parts of the country. I'm not sure I know a plumber in the entire metropolitan Chicago area who knows boilers well. I agree with most HVAC companies being clueless.
    Steve Minnich
    Tell me I can't, and I'll show you I can.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,948Member
    Plumbers, pipefitters, HVAC company, boiler tech. Doesn't matter who does it it's what they know that counts
  • corey_scorey_s Posts: 17Member
    edited June 19
    Thank you for the replies. The pump is a Alpha2 15-55F Variable Speed, 1/16 HP. Is that too small for this type of system? It was installed on the supply side after the expansion tank. JohnNY, when you say "balancing the system through the two different runs", do you mean getting the system to have high enough return temps because of the different diameter pipes and small size pump? Is the possibility of short cycling because the boiler would get to the high limit before the thermostat call for heat is satisfied? would this also be because of the large pipes and smaller size pump? The bypass is setup different from what the manufacturer shows. How is the bypass temp controlled? And how do you know when to adjust it? Do I throttle back the ball valves on the returns to limit the cold water coming into the boiler? The ball valves on the returns were left wide open. I'm guessing they would just leave them all the way open unless I complained or there were obvious signs that something is not working properly?
  • Steve MinnichSteve Minnich Posts: 2,467Member
    Those large pipes could almost run on gravity circulation. A huge pump isn't necessary.
    Steve Minnich
    Tell me I can't, and I'll show you I can.
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,644Member
    I assume you have large cast iron radiation?
    Serving Northern Maine HVAC, and Controls
  • corey_scorey_s Posts: 17Member

    Those large pipes could almost run on gravity circulation. A huge pump isn't necessary.

    I would agree, but don't the small pipes first going into the large ones restrict the flow more? And would this cause the balancing and possible short cycling issues @JohnNY described above?

    I assume you have large cast iron radiation?

    Yes, we have 10 cast iron radiators all roughly the same size as the one in the attached picture.

    The big question I'm having now is how to adjust the bypass and balance the system? Is this done by throttling back the ball valves they put on the returns? Thy left them wide open. How do I know if they need to be adjusted and how much to turn them?
  • Paul PolletsPaul Pollets Posts: 3,200Member
    A boiler bypass should have a thermometer located on the return below the bypass. It is adjusted so that the return is above 140 within 5 minutes of boiler firing so condensation is prevented. The radiators should have thermostatic radiator valves (TRV's) installed to easily balance the system and accurately control radiator temps.
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,644Member
    edited June 24
    Any reason that you didnt want a condensing boiler? Just out of complete curiosity.

    A system like yours is very well suited to them.
    Serving Northern Maine HVAC, and Controls
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