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Parts compatibility

djc2232 Member Posts: 136
Weil-Mclain ECO 70 (Series 1). Looking to pick up a few extra parts to have on hand in case of any failures. I have a series 1 ECO boiler going into its second heating season. Runs great.

Looking through the owners manual Ive noticed that there are some part numbers that are different from the series 2 manual. In some instances there are only the series 2 boiler parts in stock online, havent tried my local HVAC supplier yet.

For example. The flue temp sensor on my boiler is only listed as that. In series 2 it has a different part number but also includes the rubber grommet. There are a few other parts as well I cant find for my series in my manual but I can find the part with a different number in series 2.

Does anybody have an idea if these series 2 parts will work or do I have to dig to find the ones listed in my manual.


  • GBart
    GBart Member Posts: 746

    Follow the service and maintenance procedures given throughout this manual and in component literature shipped
    with the boiler. Failure to perform the service and maintenance could result in damage to the boiler or system. Failure to
    follow the directions in this manual and component literature could result in severe personal injury, death or substantial
    property damage.

    The boiler should be inspected and
    started annually, at the beginning of
    the heating season, only by a qualified
    service technician. In addition, the
    maintenance and care of the boiler
    designated in Figure 89, page 83 and
    explained on the following pages must
    be performed to assure maximum
    boiler efficiency and reliability. Failure
    to service and maintain the boiler
    and system could result in equipment

  • djc2232
    djc2232 Member Posts: 136
    And I do! But when the part I need is a week out in the middle of the winter. Oh and it's a holiday weekend. Just a little insurance to have I'm case a part fails and I need to replace.
  • Fred
    Fred Member Posts: 8,542
    Does Weil have an on-line parts catalog? Most parts suppliers and on-line catalogs will tell you if the Series 1 part # has been superseded with the Series 2 part # or another part #. I believe Supplyhouse.com carries and sells Weil parts. If you go there and search on your Series 1 part number, it should give you a new part number if it has been superseded. I'm not sure if it will tell you if another part is compatible, if the Series 1 part # is still a current part.
  • djc2232
    djc2232 Member Posts: 136
    They do. There were a few sites where it automatically gave me the new part number or just listed it as backorder.

    There are only a few parts in my manual that in series 2 it lists a different part number. From what I've seen it's pretty much the same part.

    Even the WM customer support couldn't give me a straight answer whether or not they would work.
  • Fred
    Fred Member Posts: 8,542
    There aren't any manufacturers or Distributors in today's supply chain that will inventory the same part under different part numbers. I would say, even though the part may look the same, there is something different in the specs, maybe input/output capacity, orifice size, flow rates, voltage, temp ranges, something that may not be outwardly obvious but you can almost bet there is a difference. From a safety perspective, I'd be inclined to buy the recommended part. Having said that, there are manufacturers that will change a part number when they change a supply source, but even then, they will usually supersede the old number when the old source stock is depleted.