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T87 NOS

GW
GW Member Posts: 4,829
Taking bids, hit me if you really need an old mercury😀
Gary Wilson
Wilson Services, Inc
Northampton, MA
gary@wilsonph.com
dave1234

Comments

  • PC7060
    PC7060 Member Posts: 1,442
    Nice.  Where did you run across those?
  • neilc
    neilc Member Posts: 2,852
    known to beat dead horses
  • Jamie Hall
    Jamie Hall Member Posts: 24,804
    !!!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Mad Dog_2
  • GW
    GW Member Posts: 4,829
    PC they have been sitting on my shelf for 20 years or so
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    PC7060kcoppethicalpaul
  • PC7060
    PC7060 Member Posts: 1,442
    edited November 2021
    Classic NOS with a Hazmat twist!

    I’ve got a couple units I pulled when I update the boiler and HVAC Systems. Not new but still worked fine after 40 years. 
  • GW
    GW Member Posts: 4,829
    PC, I’ve got a couple hundred sitting in a plastic tote. Those are considered new though, lol
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    PC7060
  • PC7060
    PC7060 Member Posts: 1,442
    So what’s the limitations on reselling?  Disclosure not the let kids play with em?  I have to say as kids we pretty routinely plays with mercury whenever we could find it. I think we were protected by all the lead paint that had gotten in our system first!
    mel57Rich_49
  • mattmia2
    mattmia2 Member Posts: 10,884
    seems like shipping could be an issue
  • retiredguy
    retiredguy Member Posts: 976
    The mercury inside the hermetically sealer bulb in a typical T87F thermostat will oxidize after a period of time rendering the thermostat useless. I do not know their life expectancy but they do normally last a long, long time.
  • ChrisJ
    ChrisJ Member Posts: 16,301

    The mercury inside the hermetically sealer bulb in a typical T87F thermostat will oxidize after a period of time rendering the thermostat useless. I do not know their life expectancy but they do normally last a long, long time.

    I always assumed mercury switches were vacuumed out or filled with an inert gas along with the mercury?

    Single pipe 392sqft system with an EG-40 rated for 325sqft and it's silent and balanced at all times.

    PC7060
  • HVACNUT
    HVACNUT Member Posts: 6,322
    Unless the mercury interacts with something else that can break it down, its forever.
    Some supply houses have bins to collect mercury thermostats so they can be properly disposed of. That's the best place for them IMO.
    Besides, now we have the Nest.🤮

    Rich_49Solid_Fuel_Man
  • Jamie Hall
    Jamie Hall Member Posts: 24,804
    No surpsise -- Gary's sending me one. The mercury switch should be forever, for all practical purposes -- they were vacuumed out and refilled with nitrogen, so unless the little bulb gets cracked... and oxidation of the terminals isn't a problem, as mercury aggressively wets them every time they operate. What does fail sometimes is the wire connections outside the bulb, from fatigue, or rarely the anticipator can burn out.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • GW
    GW Member Posts: 4,829
    Jamie If you were me, dragging many thousands of dollars out of homeowners pockets, would you leave a T 87 on the wall? A pro and a con everything I guess.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    PC7060
  • pecmsg
    pecmsg Member Posts: 5,288
    Depending on the situation, I would advise the client that its proven and has an extremely low failure rate. If they want to change it fine, if not better.
    GW
  • Jamie Hall
    Jamie Hall Member Posts: 24,804
    GW said:

    Jamie If you were me, dragging many thousands of dollars out of homeowners pockets, would you leave a T 87 on the wall? A pro and a con everything I guess.

    Depends on whether they want programming or remote sensing or control -- or might. If they do, out the T87 goes. I suspect that in many if not most situations I would pull brand new 5 or 6 wire thermostat wire and at least hook it up at the boiler end so that they really did have a common at the thermostat, so that when Joe Sixpack decides to put in a Nest or something they can hook it up... !
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    GWMad Dog_2
  • arad500
    arad500 Member Posts: 4

    Hi GW, Do you still have these? I'm looking for a millivolt Tradeline round thermostat (TS86A?). Gold, if possible!

    Really, I'm looking for any vintage millivolt options. Thanks!

    Mad Dog_2
  • mattmia2
    mattmia2 Member Posts: 10,884

    You can probably find one good used on ebay for next to nothing from someone that didn't know they need to change the thermopile every couple decades.

    Mad Dog_2
  • dko
    dko Member Posts: 668

    This is before my time, but does anyone have an idea why a plumbing supply house would have a drawer full of mercury vials? All the old-timers are gone, so I never had a chance to ask anyone. They are in ~2 dram sized plastic vials. Were they used for something that they would sell it in vials?

    Mad Dog_2
  • mattmia2
    mattmia2 Member Posts: 10,884

    some old gas regulators used a column of mercury but i don't know how much or if it was field serviced.

  • unclejohn
    unclejohn Member Posts: 1,833

    contraband

    arad500
  • arad500
    arad500 Member Posts: 4

    This is the only one I could find… Not cheap but exactly what I am looking for.

  • arad500
    arad500 Member Posts: 4

    & maybe these. Am I right to assume that anything with "A" is millivolt?

    TS86A or T855A ?
    https://www.ebay.com/itm/134480736955

  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,517

    At 55, I"m beginning the "old timer" era...and I relish it. You get instant "street cred" with the youngsters....hee hee..you can have ALOT of fun with that..I DO! I used Mercury Column Gas pressure test units up until atleast 2001 or so. You'd keep them in a 5 gallon bucket, so they wouldn't tip over and spill all over your truck or worse yet,the Homeowners basement. Inevitably, they'd fall over in the truck once in awhile, and you'd need more Quick-Silver as we called it. I had an lovely Old Timer named Joe Greenfield from "Matzo-Pizza 🍕 " (Massapequa Long Island, NY) who I bought my Ridgid 300 Pipe Threader off of...practically new. $125!!!! Along with that, we hit it off, I he gave me ALL HIS stuff..whether I liked it or not!!! Ha ha. A Hellmans Mayo Jar full of Mercury (Do the Mathl) this Bio-Hazardous Fragile jar weighed A TON.....He threw in 2 ancient rusty green Mercury Test Columns too! A Had them carefully stored for years. I saw 5 Honeywell T-87s in the original Plastic for sale at a neat Church ⛪ antique sale about 8 years ago. 20 bucks... I savor them and use very rarely to dial-in a quirky steam or Vapor system. I still have found NO SUBSTITUTE for control of a Steam system! Magic! Gary, I met you about 2000 at a Jim Davis Seminar in Penna? Met Mark Hunt and Darin Cooke there too! You can't be too far from me? Mass? Connecticut? PENNA? MAD Dog

  • GW
    GW Member Posts: 4,829

    (hand raised) not sure what the legal limits are if there is such a legal thing, I have stuff

    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • GW
    GW Member Posts: 4,829

    Matt yes that was a good long time ago!

    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • GW
    GW Member Posts: 4,829

    Yes i have some but seems like they can't be shipped

    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • arad500
    arad500 Member Posts: 4

    Thanks everyone—I'm having trouble with my 2-wire millivolt system. It controls an (ancient) gas wall heater in our rental unit.

    No thermostat has worked properly… but the unit starts up when I touch the 2 wires together. Any suggestions??

  • Jamie Hall
    Jamie Hall Member Posts: 24,804

    Not all thermostats are compatible with millivolt systems — in particular, it is unlikely that any digital thermostat will be, unless it is specifically designed for the purpose.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mattmia2
    mattmia2 Member Posts: 10,884

    If the thermopile is getting weak it may produce enough current to open the valve with the wires touched together but not through a thermostat, especially if it has an anticipator. Measure the voltage from the thrmopile open circuit and with the wires shorted together.

  • 109A_5
    109A_5 Member Posts: 1,639

    Hello @arad500,

    You probally can use any thermostat you want with a milivolt system. To do so you would have to add a 24 VAC transformer for the non-milivolt thermostat and a relay. The non-milivolt thermostat controls the relay and the relay contacts control the milivolt system. Keep in mind you probably would loose the functionality of having heat during a power failure.

    Milivolt system thermostats did not have (or use) the heat anticipator resistor.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • mattmia2
    mattmia2 Member Posts: 10,884

    oh and @Mad Dog_2 has the answer about the vials of mercury, they were for filling/topping off manometers.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,453

    @arad500

    could be the thermostat or the wiring to the stat. Millivolt circuits need low resistance. You could also use a relay near the boiler to reduce the circuit length

  • Jamie Hall
    Jamie Hall Member Posts: 24,804

    This is a good suggestion. The problem with modern thermostats and millivotl isn't so much the anticipator, as it is that the "switch" which most of them use is actually a triac — and the millivolt system simply doesn't have enough voltage to see that as a closed circuit and worse, most triac circuits only work properly on AC.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • ChrisJ
    ChrisJ Member Posts: 16,301

    I think all of the modern ones I've had all seemed to use mechanical relays.

    The VisionPro 8000 green screen thermostats and now the Prestige with the remote EIM all seem to use mechanical relays. Omron brand, I think.

    Single pipe 392sqft system with an EG-40 rated for 325sqft and it's silent and balanced at all times.

  • 109A_5
    109A_5 Member Posts: 1,639

    Lots of variety out there, dry contacts, Mercury, Thyristors, Relays and MOSFETs

    T87F 👍️

    Repairing a Nest Thermostat!
    https://youtu.be/avoJiqOE9ec

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • Jamie Hall
    Jamie Hall Member Posts: 24,804

    If they are sealed relays, they may or may not work. If they are battery or otherwise externally powered, they should be OK, provided they don't have an anticipator — but if not, not, as the millivolt generators have nowhere near the power needed.

    Open relays may work for a time, but unless they are contacts designed for very low resistance they may fail after a time.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    ChrisJ
  • 109A_5
    109A_5 Member Posts: 1,639

    Yes, even Mcdonnell & Miller has special LWCO switches for milivolt systems.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System