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soft start

I have a ground source heat pump I installed in a rural area with bad power, and every time the compressor kicks in there is a serious voltage drop in the house and has actually burned out a couple of 24V track lighting transformers. It is a 5 ton unit about 8 ft. from the 200A panel with generously sized wire.  This scenario seems to be quite common with larger compressors such as this, never had one quite this bad though, and is usually cured by adding a kick-start kit which did not help here. It is a ClimateMaster, who said a  digital soft start  should fix it  and are working on getting one to market but I need one now. I searched the web but am not sure what would be appropriate for this size unit, I called our usual refrigeration supplier who had no idea what I was talking about.

Any suggestions?


  • Techman
    Techman Member Posts: 2,144
    edited October 2010

    What is the supply voltage supposed to be ?  With the H/P  off what voltage do you have at the C/B panel  main lugs , & on the load side of the H/P unit C/B ,which HAS TO BE a "HACR" rated breaker ,& at the compressor contactor line side,&then at the compressor electrical terminals  @ startup & w/the unit running( this reading is the most important  of all ).Was that 200A panel an upgrade ? Was the overhead lines and weaterhead and  drop feeders & meter pan & the C/B  feeders upgraded ? The electrical connections at the pole can be corroded and/or loose.Do the refrigerant pressurers equalize during the off cycle ? Why not a "hard start kit " ? Are there TXV's in this unit ? Is there "anti-short cycling" for the compressor? What voltage do you have on the low volt  circuit  w/o the unit running & then @ the comp contactor upon  start up of the comp .A KickStart has to be matched to the compressor, one size is not a "fits all" . 
  • Jeff Hammond
    Jeff Hammond Member Posts: 12
    Soft start

    Enertech Manufacturing (GeoComfort & Hydron Module) and WaterFurnace have the soft start available now for rural light dimming situations. It's a product provided through Emerson (Copeland) for scroll compressors.
  • Techman
    Techman Member Posts: 2,144
    Hay Jeff

    that soft start kit,does it require the pressurers to be equalized ?
  • Jeff Hammond
    Jeff Hammond Member Posts: 12
    Soft start pressures

    Techman -- They should be equalized before it tries to start. However, most geo equipment has an anti-short cycle timer built into the control board, so they should be equalized in the 5 min. that the compressor is off.  
  • Techman
    Techman Member Posts: 2,144

    Not all ,not all the time,hence the hardstart kit . A TXV w/ a bleed port will ,for sure.
  • zacmobile
    zacmobile Member Posts: 211

    After months of anticipation I finally received and installed an Emerson Securestart which seemed to do the trick: before installation it would pull over 120 amps on start-up after was about 51 and no lights dimming! installation was a bit of a trick, not exactly plug n' play (make sure you have a bit of whatever gauge wire your compressor uses & appropriate spade connectors on hand) but went in without a hitch. And the Supco hard-start I had installed previously a few months ago was blown up and had leaked fluid everywhere. (i've had two others do this that were of the appropriate size for the unit)

    Just thought i'd share.
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