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I have 2 1960's vintage thermostats in my house. Are thermostats available that let the room temp dr

Are there modern-day thermostats that allow the room temperature to drop a few degrees before sending the "fire up the boiler" message to the boiler? I would be replacing 1960's era thermostats. Thanks for any helpful info, I appreciate your time!

Comments

  • ratio
    ratio Member Posts: 2,918
    Look for one that says 'adjustable differential'. That's the difference between the cut-out temperature and the cut-in temperature.

    Why do you want to let the temp droop? To keep the sew system operation as close as possible to it's current operation?

  • Jamie Hall
    Jamie Hall Member Posts: 17,032
    And what, besides age, is the matter with the old thermostats?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • NY_Rob
    NY_Rob Member Posts: 1,370
    edited December 2018
    Most people consider a differential drop of more than 2deg uncomfortable.
    Your old t-stat may have an "anticipator" that you can adjust to a different setting to make your boiler run longer to create longer off periods.

    https://inspectapedia.com/heat/Heat_Anticipator_Adustment.php
    SuperJdelta T
  • SuperJ
    SuperJ Member Posts: 605
    The anticipator is a hugely un-appreciated piece of mechanical control. It's so much more elegant than a simple dead-band.
    Modern dead-band based thermostats will often feel less comfortable than a anticipator based thermostat due to steady state error.
    The anticipator essentially actively adjusts the dead-band, so that the longer the heat has been off the tighter the dead-band is, and then same thing when it's on, the longer the heat runs the less overshoot it will allow. A dead-band based thermostat may let the space temp sit 1.5 degrees under the set point for hours making you feel chilly when all you need to feel comfortable is a few minutes worth of heat each hour.
    This is all much more noticeable in shoulder seasons where you don't need much heat.
    NY_RobCanuckerdelta T
  • nibs
    nibs Member Posts: 462
    @MrRogers
    If they are Mercury switch thermostats & you remove them I would like to buy them.
    Am looking for one to run my newly built radiant floor.
    PM me if you like.
  • NY_Rob
    NY_Rob Member Posts: 1,370
    ^ Plenty of unused NOS Honeywell T87F Round mercury t-stats available on ebay. Just search for "T87F".
  • nibs
    nibs Member Posts: 462
    @NY_Rob ............... Thank you, had looked there, but did not have the number.
  • NY_Rob
    NY_Rob Member Posts: 1,370
    I just bought two NOS T87F's a couple of days ago off ebay... one for $29 and another for $39. Looking forward to using them with my mod-con.
  • MrRogers
    MrRogers Member Posts: 4
    My boiler keeps trying to fire back up too soon, then it just turns itself back off. It does that over and over, till it finally actually needs to start up, then it starts and stays running. I'm trying to save the gas valve needless cycling.
  • Fred
    Fred Member Posts: 8,518
    MrRogers said:

    My boiler keeps trying to fire back up too soon, then it just turns itself back off. It does that over and over, till it finally actually needs to start up, then it starts and stays running. I'm trying to save the gas valve needless cycling.

    Are you using a programmable thermostat? Do you have it programmed for 1 cycle per hour? They come with a factory default for forced air, which is 5 cycles per hour.
  • ratio
    ratio Member Posts: 2,918
    Does the boiler make your hot water as well? Something's not right, but there are a number of other things it could be aside from the stat.

    Is this a new thing that started recently?

  • Mike Cascio
    Mike Cascio Member Posts: 140
    1960’s thermostat. You guys and your new fangled technology. You need to use a series 10 thermostat from the 20’s with bimetallic strip only.
    ratio