Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Indirect water heater coils

Docfletcher
Docfletcher Member Posts: 487
Will a indirect water heater coil work in reverse? That is to say extract heat from the tank the coil is in for a special application?

Comments

  • HVACNUT
    HVACNUT Member Posts: 5,803
    ?
    What are you trying to do?
  • Tinman
    Tinman Member Posts: 2,808
    Water and water on each side? What’s the application? Trying to avoid the appropriate heat exchanger?
    Steve Minnich
  • GroundUp
    GroundUp Member Posts: 1,888
    Yes, but how does the heat get into the tank in order to be extracted? I've been around a handful of combi-cor type units that are basically a powervent water heater with an indirect type coil in them intended for space heating, presumably similar to what you're looking to achieve.
  • Tinman
    Tinman Member Posts: 2,808
    But we don’t know what he’s trying to achieve yet.
    Steve Minnich
  • GroundUp
    GroundUp Member Posts: 1,888
    He's trying to extract heat from an indirect coil- exactly what a combi-cor is designed to do. Why though, no we do not.
  • Docfletcher
    Docfletcher Member Posts: 487
    Well I had the thought that if the indirect circulator came on every time a zone called for heat the boiler when cold started would always have at least 130F water so then no condensation. That would mean the heating zone and indirect zone would need function at the same time. For me it would be a way to salvage a old boiler that may not be worth spending allot of money on. Is it possible for the boiler to do both zone heat and the indirect the same time ?
  • Docfletcher
    Docfletcher Member Posts: 487
    edited October 2018
    I didn't want to scare up old memories but some of you may recall my old Weil Mclaine GV 4 Series 2 and the discussions of failed thermostatic devices on these boilers.
  • HVACNUT
    HVACNUT Member Posts: 5,803
    If I understand it, your first post was a little misleading.

    You absolutely need a limit control on the indirect, so no, it cant just run away with every space heat cycle.

    What boiler and boiler aquastat is there now?

    You state the boiler is old and you want to salvage it. If it wont be too long before replacement then I wouldn't worry much about condensation.

    If its an oil fired boiler, I would recommend a brush and vac of the boiler, base, and smoke pipe at the end of the heating season so it will be dry and clean come autumn.
  • Docfletcher
    Docfletcher Member Posts: 487
    edited October 2018
    This a Weil McLain NG boiler GV4 Series 2. The aquastat is whatever is mounted in the HTP indirect.

    I noticed this morning when the indirect aquastat calls for heat it's circulator (circuit) works even if any of the heat zone circulator (circuits) are on and working. So, that would suggest to me that this boiler has enough nut to do both at the same time. If the indirect came on whenever a zone called for heat It would only need to stay on long enough for the boiler water to reach 130 degrees or so. Maybe a timer/relay setup could be placed to kill power to the indirect circulater after 90 seconds or so. The idea is to commingle the heat of the indirect tank water with the cold start water of the the heating zone.

    It's just an idea, Maybe tenable maybe not.

    Thermostatic parts for this boiler are un-obtanium. Weil McLain work around (Service Bulletin SB0401R1) is not really an option but Caleffe makes several thermostatic valves which might be an option. I'm not sure though. Maybe the 280 could be fitted in.