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How good are mercury thermostats?

Fizz
Fizz Member Posts: 547
Getting impression that mercury t-stats are very good! The one I have when adjusted to proper heat anticipator setting is very accurate, and seems like it'll last forever, as it's already 40+ yrs.

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 23,168
    They're superb. Along with mercury pressuretrols and vapourstats. The contacts (mercury) do last forever, there are very few moving parts, etc. etc. If you have one, keep it! Far superior to the newer ones, either all electronic (for thermostats) or microswitches (for pressure controls).

    The only thing wrong with them is you don't want to smash the mercury bulb and drink the mercury. So who's going to do that?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Canucker
  • ratio
    ratio Member Posts: 3,615
    Yup. Mercury stats & roaches are a few of the things that will survive Armageddon. Couple one with a millivolt gas valve on a 1 pipe steam system & you'll be about as well set as possible for the coming grid collapse.
    But, you can't change the setpoint from your iPhone, so fail.
    </humor>
  • Fizz
    Fizz Member Posts: 547
    Hey, I used to play with Mercury when I was a kid, now 70, so I'm glad I didn't drink it. Like most other things that last forever or for what they were used were very good are now on forbidden list. Where have the roaches gone???
  • BobC
    BobC Member Posts: 5,476
    I have a mercury contactor I took out of an old wave solder machine. It's rated at 50A 240V, it has two capsules about 3" long that are about 1/3 full of mercury. When the coil energizes two slugs get pulled into the mercury pools.

    It was over 40 years old when I removed it and worked just fine thank you.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Canucker
    Canucker Member Posts: 722
    Very good?! You can have my mercury filled T87 when you pry it from my cold, dead hands ;)
    You can have it good, fast or cheap. Pick two
    ratio
  • BobC
    BobC Member Posts: 5,476
    I have 2 T87's (low temp version) sitting on the shelf downstairs, I never throw anything out.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge