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Low ambient disable for split system

Sorry if this post is crude I'm on my phone. Does any thermostat support disabling the compressor below a set outdoor temp?
Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment

Comments

  • IronmanIronman Member Posts: 5,573
    Honeywell TH8300 series with an outdoor sensor.
    Bob Boan


    You can choose to do what you want, but you cannot choose the consequences.
    ChrisJ
  • njtommynjtommy Member Posts: 1,105
    Vision pro 8k or higher will do it. Most heat pump t-stats that have out door air temp sensor capabilities will do it no problem. Getting ready for you heat pump?
    ChrisJ
  • ratioratio Member Posts: 2,351
    Look for a stat labeled as "dual fuel", that should almost assure you a low ambient lockout.

    Also, another vote for the Honeywell 8000 series, which can use a wireless or wired outdoor sensor. I'm a little leery of using wireless for that kind of control.

    njtommyChrisJ
  • njtommynjtommy Member Posts: 1,105
    edited September 2016
    For the new vision pro 8000 you can do it from what they call the cloud aka the Internet
    ChrisJ
  • ChrisJChrisJ Member Posts: 10,870
    So wait,
    My current 8000 series would do it if I connect an outdoor sensor?

    It could be set for, say 55F and it would lock it out?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • njtommynjtommy Member Posts: 1,105
    Is your current 8000 t-stat heat pump compatible?
  • ChrisJChrisJ Member Posts: 10,870
    njtommy said:

    Is your current 8000 t-stat heat pump compatible?

    Yes,
    But it looks like I need a TH8320/TH8321 for the lockout option but even then, it only allows up to 40F. I'd want 50-55F.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNEJUGHNE Member Posts: 6,797
    Are you getting a heat pump or simple AC. The above references are, I believe, to lock out a heat pump for maybe a dual fuel set up.

    My guess it that you want a LACO for your AC to keep it from running when below 55. I have seen simple close on rise button t-stats inside a Carrier unit.....maybe 55-60 degree to close.
    ChrisJ
  • ChrisJChrisJ Member Posts: 10,870
    JUGHNE said:

    Are you getting a heat pump or simple AC. The above references are, I believe, to lock out a heat pump for maybe a dual fuel set up.

    My guess it that you want a LACO for your AC to keep it from running when below 55. I have seen simple close on rise button t-stats inside a Carrier unit.....maybe 55-60 degree to close.

    Yes, just as a safety device for cool only.
    Do you have a link for what you're using? My dad also wants such a thing on his system.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Harvey RamerHarvey Ramer Member Posts: 2,214
    Install a Nema 3-r mechanical thermostat in the outdoor unit that breaks the wire to the y terminal.
    Ramer Mechanical
    ramermechanical.com
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • njtommynjtommy Member Posts: 1,105
    You could probably do it with a $20 Klixson if you can track down the right part number.
    SWEI
  • ChrisJChrisJ Member Posts: 10,870
    This may come across as silly but, why don't the outdoor units come with such protection?

    Wouldn't it help on warranty repairs?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNEJUGHNE Member Posts: 6,797
    edited September 2016
    The one I saw was in a 5 ton unit at a church that I service.
    It is a simple button hanging on control wires connected with 1/4" push on terms.
    Some Carrier/Bryant tech here may know a part number.
    It was NEMA 1 device sheltered from the rain.

    It is one of those 5 dollar items that you can buy for maybe 20 bucks.
    ChrisJ
  • njtommynjtommy Member Posts: 1,105
    Good find @ratio
  • ChrisJChrisJ Member Posts: 10,870
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNEJUGHNE Member Posts: 6,797
    That is similar to what I saw.

    Did you notice the ICM site specs 55 degrees +/- 9*
    Supply house site specs +/- 5*

    These could save many compressors where many hands are on the T-stat. (Public places....churches etc.)
    It is one thing the layman public person can not over ride ;)
  • ChrisJChrisJ Member Posts: 10,870
    JUGHNE said:

    That is similar to what I saw.

    Did you notice the ICM site specs 55 degrees +/- 9*
    Supply house site specs +/- 5*

    These could save many compressors where many hands are on the T-stat. (Public places....churches etc.)
    It is one thing the layman public person can not over ride ;)

    That's why I want one.
    Even with only my hands on the thermostat, accident's happen and with something so easy and cheap to protect it I don't see how you couldn't.

    I really don't understand why manufacturers aren't including these in the product.

    The downside is the airhandler will still run and the indoor thermostat won't say anything. I guess, unless you looped the indoor t-stat run outside to the sensor somewhere. That would take both the air handler \ furnace and the condensing unit out.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNEJUGHNE Member Posts: 6,797
    2 Amps max.

    Fan only running will tell you someone is playing with T-stat.
    The placebo effect of fan running will "cool" some people off.
    That is why Placebo T-stats are popular. >:)
  • ChrisJChrisJ Member Posts: 10,870
    JUGHNE said:

    2 Amps max.

    Fan only running will tell you someone is playing with T-stat.
    The placebo effect of fan running will "cool" some people off.
    That is why Placebo T-stats are popular. >:)

    I certainly hope that contactor doesn't exceed 2 amps. If it does I really oversized the system. :)

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ChrisJChrisJ Member Posts: 10,870
    Looks like a delay is recommended when using the ICM SC055 for this as well. Going to order both a 5 minute delay and 55° thermostat.

    Here's the delay.

    http://www.supplyhouse.com/ICM-Controls-ICM201F-ICM201F-Delay-on-Break-Timer-6-Wire-Leads-5-Minute-Delay

    And the thermostat
    http://www.supplyhouse.com/ICM-Controls-SC055-SC055-Dryout-Thermostat-Low-Ambient-Cutoff-Switch-55-F?gclid=CJmd18uwkc8CFU5bhgodixoLuQ


    Seems like extremely cheap insurance to me.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • SWEISWEI Member Posts: 7,356
    JUGHNE said:

    Did you notice the ICM site specs 55 degrees +/- 9*
    Supply house site specs +/- 5*

    Fahrenheit versus Celsius?
  • ChrisJChrisJ Member Posts: 10,870
    SWEI said:

    JUGHNE said:

    Did you notice the ICM site specs 55 degrees +/- 9*
    Supply house site specs +/- 5*

    Fahrenheit versus Celsius?
    I don't know, I'd assume a typo.
    I just emailed ICM for clarification as my dad isn't liking the +9 possibility. He's been known to fire the system up when it's in the low 60s and humid out.



    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • SWEISWEI Member Posts: 7,356
    I'm somewhat unclear whether it represents setpoint tolerance or deadband.
  • JUGHNEJUGHNE Member Posts: 6,797
    Both sites said F* I believe.

    Many control transformers have a 3 amp fuse in the 24 VAC secondary.......only open with a problem in system. The 2 amp for the contactor should be good.

    Most T-stats have a programmable time delay (up to 5 minutes) for compressor, the "cool" flashes while you wait. That has been enough usually.

    For cooling below 65 or so ambient, many use the ICM head pressure control for the AC. It varies the cond fan motor speed based on the liquid temp in the unit.

  • ratioratio Member Posts: 2,351
    If there anything fancy (zoning, etc.) going on, or I think there's any chance it'll need to operate when it's cool out, she gets low ambient kit. Head pressure, cch, freezestat, the works.
  • ChrisJChrisJ Member Posts: 10,870
    edited September 2016
    ratio said:

    If there anything fancy (zoning, etc.) going on, or I think there's any chance it'll need to operate when it's cool out, she gets low ambient kit. Head pressure, cch, freezestat, the works.

    I was looking into this for my setup, but Trane / AS claim it's safe down to 55F stock, and down to something like 40F with defrost control, but I could never find out what "defrost control" is or if the TAM7 airhandler comes with it. It's certainly not listed as an accessory.

    Is a low ambient kit still beneficial to these units at cooler temps and can the ICM control vary a single speed fan motor? I thought most setups simply cycled the condenser fan on head pressure?


    With a low ambient setup I wouldn't be concerned about low temp protection, the unit would be fine at 40-50F should it end up on some how.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ratioratio Member Posts: 2,351
    There're pressure switches that will cycle the fan on & off, & a number of devices to vary the speed of the condenser fan. I've used these with good success. ICM also offers a selection. In fact, I almost bought one this morning for a unit that I'm expecting to kit up for a long dehumidification season. Then there's the Big Boy stuff, flooded condensers, head pressure control valves, accumulators, receivers, all sorts of neat stuff, but not perhaps cost effective for residential work.

    And I still haven't looked up those manuals yet, but I will.

    ChrisJ
  • ChrisJChrisJ Member Posts: 10,870
    ratio said:

    There're pressure switches that will cycle the fan on & off, & a number of devices to vary the speed of the condenser fan. I've used these with good success. ICM also offers a selection. In fact, I almost bought one this morning for a unit that I'm expecting to kit up for a long dehumidification season. Then there's the Big Boy stuff, flooded condensers, head pressure control valves, accumulators, receivers, all sorts of neat stuff, but not perhaps cost effective for residential work.

    And I still haven't looked up those manuals yet, but I will.

    Do you typically do a crank case heater with one of these controls or no?

    It looks like all you do is strap a sensor onto the condenser, wire the badboy in and tweak two settings on the ICM controller and you're up and running when it's chilly out.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ratioratio Member Posts: 2,351
    You should. If it's going to operate in cold weather, then for sure, but if you think you're just going to go a little further into the swing season then I might not.
  • JUGHNEJUGHNE Member Posts: 6,797
    I have seen/installed the ICM variable speed controller on AC units for commercial kitchens, flower shop with reach in self contained compressor which overheated the building on cooler days, and movie theater which requires cooling dependent upon occupancy count.
    You probably don't need it if you don't run AC below 55* amb. IMO.
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