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New Install Having Compressor Issues See Video

Hello to all
I installed a new air handler and condensing unit at beginning of the summer. Flushed lines, pulled vacuum and charged. The customer would sometimes hear a noise from the condensing unit, sometimes the temp went up in the house and sometimes it was ok. I went to the house 4-5 times. One time the compressor was overheated, but usually when I got there 20-25 minutes later it was running. Not sure if it overheated and reset or just started to work again. I left a single gauge on the high side of the unit so he could take a look when it happens and finally after one month of working fine it happened twice yesterday. The unit makes a very loud rumbling noise and one time it was stuck at 200 PSI (410A system) and one time it was at 250 PSI and fluctuating a little. Thats less then standing pressure as its 90 degrees. Any suggestions?
I tried to attach a video but it does not seem to work. Can a video be added to this forum? I think it would be good to see the video.
Thanks, Michael.

Comments

  • mattmia2mattmia2 Member Posts: 1,438
    Oil slugging and preventing vapor or refrigerant from flowing somewhere?

    What is the refrigerant control?
  • ChrisJChrisJ Member Posts: 11,073
    edited July 23
    I would upload the video to youtube and post a link.

    If the compressor is overheating, and that low highside pressure makes me think it's undercharged or something is funky with the metering device. Can you share pictures of the install? Does it have a TXV? Where's the bulb located etc?

    For R410A I'd expect to see a high side of 275-325 PSI.

    What's the SH and SC?
    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
  • IronmanIronman Member Posts: 5,683
    Have you checked that everything electrical is correct? Wiring, Voltage, amp draw, capacitors?
    Bob Boan


    You can choose to do what you want, but you cannot choose the consequences.
  • clammyclammy Member Posts: 2,505
    Sounds like your under charged , what is the metering device on the indoor evap ? Did you take a sub cooling and super heat measurements, if the compressor is shutting off on temp then u have no superheat and are under charged . If you have a expansion valve on the coil you can start off w 10 degreee sub cooling or better yet look on the condensers tag , they will usually give you a recommended sub cooling . Usually on 410 where running 300 and upwards depending on the load and how hot it is outside . Re check your charge Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • pecmsgpecmsg Member Posts: 1,450
    Are there high and low pressure safety’s on the condensing unit?

    Could be a pressure relief letting go.
  • charliechicagocharliechicago Member Posts: 109
    I am posting a video of the compressor. Make sure the sound is on to hear the noise. The system is charged properly, 12 sub cool. Runs great when it works. Voltage and amperage are good when it runs properly. You will see in the video I left my amp meter on and it shows 5.6 amps or so, but Im not sure it was reading properly because it shows microamps in the bottom corner. Thanks.
    https://drive.google.com/file/d/1kWT7C-q1VhFfvzWRlRpFTv8aqfksXd5H/view?usp=sharinghttps://drive.google.com/file/d/1dTRXBfYS1QgKfKtxHQZsCrkb6FCZ9XbV/view?usp=sharing
  • unclejohnunclejohn Member Posts: 1,572
    Maybe it's running the wrong way. Meaning the compressor is spinning backwards.
  • charliechicagocharliechicago Member Posts: 109
    Can a single phase compressor run backwards?
  • mattmia2mattmia2 Member Posts: 1,438
    It is reading milivolts according to the display. i have had the contacts i the mode switch of cheap multimeters get dirty and make intermittent contact and had them read the wrong function or some combination of functions so that current reading is a bit suspect. What is the ratings plate current? ~1500 w seems low for any condenser.

    Look at about the 4th from the last post here from @EdTheHeaterMan for the formula to measure the capacitance of the motor capacitor using the voltage and current through the capacitor and compare to the marked value, perhaps it is weak:

    https://forum.heatinghelp.com/discussion/180290/capacitor-testing#latest
  • ChrisJChrisJ Member Posts: 11,073
    edited July 26
    Can't help you if you don't answer the questions ....

    Does it have a TXV and if so where is the bulb installed?


    What's the lowside doing? What's the superheat?
    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
  • subcooler_65subcooler_65 Member Posts: 17
    You're not moving refrigerant. You are flooding the condenser and the compressor is bypassing. You have a restriction in the system, most likely the metering device.
  • charliechicagocharliechicago Member Posts: 109
    Valid point Chris J
    It’s a txv, like I said 12 Degree sub cool. It’s a heil, txv comes strapped inside, it is still right where is was originally. Don’t know the low side or sh. I know, how can you troubleshoot without info. The problem is it happens when I’m not there and then corrects itself before I can get there. I only attached, to the high side, one of those single gauges that you can leave on the unit for pressure testing. That’s all I had.
    It seems to not be pumping or very little, at 250 psi and 90 out. I’m thinking closed txv or something with the compressor. I had checked the capacitor and was fine. Could change it.
    But what’s with the noise? Closed txv I don’t think would do that. Maybe a chattering contactor?
  • charliechicagocharliechicago Member Posts: 109
    I hear you subcooler65
  • IronmanIronman Member Posts: 5,683
    edited July 26

    Can a single phase compressor run backwards?

    Yes, if the start and run windings are wired in reverse.

    Bob Boan


    You can choose to do what you want, but you cannot choose the consequences.
  • ChrisJChrisJ Member Posts: 11,073
    Need to know what they lowside is doing and need to know tht bulb location. If the bulb was installed for vertical and it's installed horizontal etc it could be wrong. Was it ragged off when brazing?

    Is it even strapped to the pipe?

    Did your flow nitrogen while brazing?
    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
  • pecmsgpecmsg Member Posts: 1,450
    > @Ironman said:
    > (Quote)
    > Yes, if the start and run windings are wired in reverse.

    Won’t happen
    Start and run are the same phase
  • ratioratio Member Posts: 2,496
    Would try to run backwards, but likely burn out the start windings pretty quickly. Unless it's a Bristol, then it'd run at IIRC 50% capacity.
  • mattmia2mattmia2 Member Posts: 1,438
    Does it do it only from the beginning of a cycle or can it start during a cycle with the compressor already running??
  • charliechicagocharliechicago Member Posts: 109
    Mattmia2
    That’s a good question. I have a feeling it happens at the beginning of the cycle, although I can’t be sure. One time the customer called me and five minutes later when I called him back he said the noise went away already and was running fine which might mean it only happens on startup.
  • mattmia2mattmia2 Member Posts: 1,438
    Ok. Does it sometimes start working properly in the middle of a cycle?
  • charliechicagocharliechicago Member Posts: 109
    I don’t know.
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,098
    By now the compressor is probably toast. Shut it down check everything and start from scratch
  • IronmanIronman Member Posts: 5,683
    edited July 27
    pecmsg said:

    > @Ironman said:

    > (Quote)

    > Yes, if the start and run windings are wired in reverse.



    Won’t happen

    Start and run are the same phase

    Paul,
    Yes it will. The run capacitor alters (shifts) the phase of the winding it's connected to causing it to act like another phase.
    If you have, or had, an Annie compressor tester this is what it would do (reverse the rotation) to free a stuck compressor.
    Bob Boan


    You can choose to do what you want, but you cannot choose the consequences.
    ChrisJmattmia2
  • mattmia2mattmia2 Member Posts: 1,438
    Ironman said:

    pecmsg said:

    > @Ironman said:

    > (Quote)

    > Yes, if the start and run windings are wired in reverse.



    Won’t happen

    Start and run are the same phase

    Paul,
    Yes it will. The run capacitor alters (shifts) the phase of the winding it's connected to causing it to act like another phase.
    If you have, or had, an Annie compressor tester this is what it would do (reverse the rotation) to free a stuck compressor.
    I recall somewhere in "Modern Refrigeration and Air Conditioning" it saying to wire the compressor like this to unstick it.
  • unclejohnunclejohn Member Posts: 1,572
    This can happen.
    A less likely possibility for reverse running is one that occurs for single-phase motors. In this instance, the
    rotor must have a certain amount of rotational speed in the reverse direction before power is applied. This can occur
    during a momentary loss of power to the compressor motor (e.g. power flickers during thunderstorms). Since the
    pressure differential across the scrolls can quickly drive the crankshaft in reverse, when power is reapplied the
    compressor may continue to run backwards. When this occurs, the motor will only run for a short amount of time
    before the motor protector will stop the motor. Since the compressor will restart in the forward direction, the
    potential for damage is less significant.
    Ironman
  • unclejohnunclejohn Member Posts: 1,572
    So did you get to the bottom of it?
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