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.

Dead band

Options
Dale
Dale Member Posts: 1,317
in THE MAIN WALL
Could you please give me a definition of "dead band" as it pertains to thermostats? My co workers like Hendrix and Joplin but I'd like to be able to explain the term from a HVAC viewpoint.

Comments

  • Bill_14
    Bill_14 Member Posts: 345
    Options
    Dead Band Capability.

    The dead band control consists of a 5° - 10°F "band" on the thermostat. It eliminates the possibility of simultaneous heating and cooling. When temperatures fall within the 5° - 10°F zone on the band, say 68° - 73°F, neither heating nor cooling can occur. A dead band might compromise comfort, and may be unacceptable in situations where there are elderly persons or invalids.

  • Bill NTSG
    Bill NTSG Member Posts: 321
    Options
    To Add

    to what Bill already said, some commercial application [residential too] have an auto-change over feature. The t-stat will automatically switch from heat to cool. This could drive the system nuts with out the "dead band" between heat and cool. Kinda' like a dog chasing it's tail.
  • BillW@honeywell
    BillW@honeywell Member Posts: 1,099
    Options
    Dead band

    The other two "Bill's" did a good job of explaining it. It was a control philosophy most common in the 1970's, and also was called "Zero Energy Band". Some pneumatic commercial stats were specifically designed to use it, so were some special T87's for use in government buildings during the oil crisis. The concept has been replaced by better controls with "adaptive intelligent recovery" from setback, and other energy-saving features.
  • Dave_13
    Dave_13 Member Posts: 110
    Options
    Deadband ......

    What I consider deadband is a range around a setpoint where nothing happens or a range that makes equipment not cycle on and off. If you have a thermostat set for 70- It may come on at 68 and heat to 72. That's a 4 degree deadband. If there wasn't one, it would cycle constantly. My 2 cents...
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928
    Options
    Potential Customer for you Bill

    Denver Sheraton West (where Wetstock was held).

    Rooms had t-stats that I hadn't seen before. Two slider adjustments--one for heat, one for cool. No other switches, etc.

    Being morbidly curious I set both at the same temp to see what would happen.

    Guess what--A/C, then heat, then A/C in a rapid sequence. Made the room quite uncomfortable. It can't do much for their energy consumption either...
  • bb
    bb Member Posts: 99
    Options
    dead band

    The dead band is the range of temperatures we are all aiming for, where the equipment is doing nothing. For example if the heating set point is 70 and the cooling set point is 75 there is a 5-degree dead band in which you are comfortable. Below 70 degrees you will be cooler than you wish, and the heat will come on. Above 75 degrees and you will be too warm so the AC will come on. If you are not comfortable when the temperature is in the dead band, (70 – 75) you need to reset the dead band to a more comfortable setting, i.e. 71 and 73 which is a 2 degree dead band.

    The biggest problem encountered with dead bands is when people are unable to adjust the dead band to meet their particular comfort level. So it is imperative that you buy a thermostat with an adjustable dead band.

    Another function of the dead band is, as some people have said, to prevent the heating and cooling from fighting against each other. The industry minimum dead band is generally 2 degrees; the maximum is adjustable to your particular comfort needs.

    Adaptive recover has nothing to do with dead band. The set back period has its own dead band.
This discussion has been closed.

Categories