Page 1 of 3 123 LastLast
Results 1 to 13 of 31

Thread: Economizer Help

  1. #1
    Join Date
    Apr 2014
    Location
    St Louis
    Posts
    64
    Post Likes

    Economizer Help

    OK so i get the basics about economizers. . .i know its got the enthalpy sensor and air mix sensor A B C D settings for climate regions and min position settings that they revert to. . my question is. . .is anyone really familiar with the wiring on these guys such as in diagnosing whether or not your actuator motor is bad or if its not receiving voltage. .The reason why i ask is today i had one acting goofy everything responded as normal i had the green light (FREE COOL) but the dampers never opened. would really like some literature on these too. . .
    going back tomorrow to diagnose it and dont feel like calling tech support

    HONEYWELL

    MOD# W7212A1025

  2. #2
    Join Date
    Apr 2012
    Location
    Cape Coral Fl
    Posts
    186
    Post Likes
    Should of had power to operate the motor (with green light). Sometime you need to disconnect motor from the damper and make sure the damper is not jammed up (Econ doesn't gets used that often, pending local) . If you can get the green light and the damper arm won't move and you have voltage, time to replace. GL

  3. Likes Lasher627 liked this post.
    Dislikes Lasher627 disliked this post.
  4. #3
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    5,445
    Post Likes

  5. Likes Lasher627 liked this post.
  6. #4
    Join Date
    Apr 2012
    Location
    Cape Coral Fl
    Posts
    186
    Post Likes
    Beat me to it slctech, Just downloaded W7212 info. Was looking for an email address. WTG. Love Google on the job when there are no schematics or info on what your looking at.

  7. #5
    Join Date
    Apr 2014
    Location
    St Louis
    Posts
    64
    Post Likes
    Thread Starter
    damn thanks man that is some very useful stuff gonna print some of that stuff off. . .especially the HW cust support book with formulas thanks. . .

  8. #6
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    5,445
    Post Likes
    Most basic and conventional actuators for Honeywell will have a constant 24v AC feeding them across the TR and TR1 terminals. To drive the actuator open or closed is based on a DC volt output from the module's "+" and "-" terminals to the actuators VDC IN terminals. 0-1 vDC is closed and 9-10vDC is open. The module will drive the actuator open or closed in increments based on the DC voltage out put. So at 5vDC your about mid way. You may have 3.3vDC or 6.4vDC for example, would have to interpolate that to figure your percentage of open or closed.
    So troubleshooting is nothing more than checking for 24v AC at actuator.....then with voltage feeding the internal guts, you are now looking for DC voltage to the actuator...if you have, for example, 5vDC to the actuator, and your actuator is just setting there clicking, popping, or doing nothing at all...well you get the jist of it.

    With the modules that attach directly to the actuator, one can make a test kit. You can remove the module from the actuator and using a set of female spade on one end and male spade on another jumper wires about 10" long...can check that way.

    Read through the troubleshooting guides, stop by RadioShack and grab a few of the resistors (meaty ones- wattage doesn not matter) reason is to make them durable as you can add wire and spade connectors to them and they become a solid member of your diagnostic tools family. A good potentiometer is good to, to simulate the ohm vs temperature chart off of many of your NTC sensors. Can use a sharpie to mark on the potentiometer the min and max ohms. A 50k potentiometer is suffice for the job.

    The VDC output on actuators is nothing more than a good testing point for what the module is inputting to the actuator. The OUT terminals are used in building automation and also for high end rooftop equipment to feedback to the main controller and allow it to convert it to percentage open. Thus in many cases you can check on an economizer from a Lennox Prodigy board or be in a computer room checking out all the equipment and can see if the position of the economizer. But in most basic equipment these terminals are unused.

    Many times the actuator is operational, but does not have enough motor torque to overcome snagged or jammed damper assemblies. Good to make sure that dampers are smooth and glide open and shut with little effort.

    A secret device that will only tell you that the actuator will drive open and when removed, spring shut.......is a fresh 9v battery. That's all it will do though. May get 5 t o10 runs on the battery, but think about it....food for thought.

    I hope your seeing that basic economization is really not that hard and proud that your taking this on and attempting to do it right.

    So many guys are intimidated by it, and once I set down and teach them about it, that light bulb comes on and they realize that it is actually one of the easiest things to troubleshoot and understand. I will say that when you get into commercial, especially large buildings with pneumatics, and massive dampers that are 20 foot high and 30 feet wide operating on monster actuators and crazy mixed air controls and solid state staging controls, there is a lot of head scratching.

    I will admit and I am sure all others who play with economization will admit, too. The most frustrating and tough thing is tinkering with the damper rods, rod set screws, actuator drive arm position, etc to try and get the full open and full close swings of the actuator to match perfectly with the full open and full close of the dampers Not bad when your dealing with a factory economizer kit, but you will understand someday.

  9. #7
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    5,445
    Post Likes
    The Mods may deem this too much info and move it to the Pro forum, but I tried to keep it borderline, helpful.

    The thing with honestly understanding economization is that it is a VERY important means of generating more revenue for you or your company. Being able to properly educate the property or building owner on the dire importance and HUGE money saving benefits, one can sell economizer kits on units that do not have it or sell the repairs. Most RTU units even old ones, you can still get kits for. I have yet to ever have issues getting one, manufactures had them built by third party companies like MicroMetl and others, and though a few weeks out, they can still be custom ordered. Your distributor may say no and it is obsolete...sure some older styles like the Carrier jack screw and accompanying controls may be, but the newer versions that will still pop into place can be custom ordered...just need to be smarter than the counter guy using nothing but the keyboard and his monitor to say YES or NO. And the new JADE can be bought as a kit with a module, actuator, and at least two sensors for basic rebuilds of most of not all light commercial units.

    I hear a lot of techs telling me how this time of the year is dead, but for me, this is when economization is the most important. Your not beating the heck out of compressors and spinning the meter wildly on mechanical cooling. You are offering the owner to take advantage of what Mother Nature is offering free of charge. I have churches, malls, movie theatres, etc. that may be cooling year round due to high latent loads....a lot of people and electronic equipment all mingled...could up-sell low-ambient and crank case heaters or could set down and plot the kilowatt usage with the owners and actually, for once, show them how to make their money back in MONTHS on an initial investment, than in many YEARS.

    Your friend in the industry, SLCTECH

  10. Likes Scott Kline, buford liked this post.
  11. #8
    Join Date
    Apr 2014
    Location
    St Louis
    Posts
    64
    Post Likes
    Thread Starter
    well Micro Metl commonly used by carrier utilizes honeywell controls right ?

    nearly every customer we have, their units have econo's on them so im always checking them and making sure they are working setting min pos and stuff like that once and a while i run across one thats not working but i want to generate more revenue and work so i want to be able to thoroughly troubleshoot them and get more repair work.

    thanks again for the reply it helped tremendously and if you have any information on the TRANE econo's that'd be great! some good pdf's i can DL

    i saved alot of the ones you posted and have them transferred to the ipad already

  12. #9
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    5,445
    Post Likes
    Get your pro status and we can get more indepth. But your going to find that a majority of your economization packages if not using proprietary factory main control modules, will be utilizing a module of some sort (Honeywell, Johnson Controls, Belimo), sensors, and an actuator of some sort. All the same concepts.

  13. #10
    Join Date
    May 2013
    Location
    Edmonton, Alberta
    Posts
    19
    Post Likes
    Wicked links. Much obliged.

  14. #11
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    5,445
    Post Likes
    Another great link....
    http://hvac.amickracing.com/Controls...ol%20Guide.pdf

    This manual is what I have been using in my classes. It deals with not only the new but the old controls and retrofitting applications.......takes the mystery out of the older stuff!

  15. #12
    Join Date
    Jul 2014
    Location
    Apache Junction, Arizona
    Posts
    1,132
    Post Likes
    excellent information...

  16. #13
    Join Date
    Nov 2006
    Location
    Southeastern Pa
    Posts
    32,183
    Post Likes
    Bear in mind...

    the economizer section only receives power when the fan runs. I recall this from an experience I had on a Carrier RTU.

    Since the manufacturers are using someone else's design (Honeywell's) I believe you will find this to be the case on other units as well..

    The Lennox L series uses an accessory board mounted on the IMC, in place of the Honeywell logic module.

    Note that the enthalpy sensors and logic modules have a very high failure rate. Honeywell has changed the system to the new Jade design, which can replace the logic module in the Carrier RTU's, as the actuator motor can be driven by the Jade.

    Strangely, Carrier does not yet provide its own retrofit kit for existing RTU's. You have to order generic Jade parts and configure them yourself.

    HTH.
    [Avatar photo from a Florida training accident. Everyone walked away.]
    2 Tim 3:16-17

    RSES CMS, HVAC Electrical Specialist
    Member, IAEI

    AOP Forum Rules:







Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Contracting Business
HPAC Engineering
EC&M
CONTRACTOR