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bad compressor?

i had a two ton r22 split ac on a basement gas furnace not cooling today.30# suction readind 90 to 100# head. had high super heat and was acting low on chge. tried putting some freon in and no changes. shut high side service valve and wouldnt pump down. closed low and no changes to speak of. compressor sounded bad. didnt act like restriction, indoor fan going and not low super heat anyway. super heat high except a little frost showing at compressor inlet and near suction shu off valve but evaporator and coil was not icing and warm. very strange situation. stuff is older and wants new complete ac system with 410a after seeing this go on and we have hot weather coming. i thought maybe compressor was just not doing anything at all.compressor wasnt building pressures when shutting service valves and freon seemed not to do any thing at all it was just going in and no results. i thought usually suction would be high and head low when compressor junk. it had all the sighns of under cge but wouldnt build up.also one other thing was when i shut it off the system was about 60 # on low and high rather than pin gauges into 120 or more like on normal systems. i am sure system is not low either. two weeks ago i put a little in and noticed superheat and suction was high but had high load inside home and it just didnt seem to be cooling all that well and was 95 degrees outside and was happy to get some relief and then this other situation popped up...a real head scratcher and would like to know what was going on for knowledge even though he wants upgrade on unit!!!   thx


  • Empire_2Empire_2 Member Posts: 2,343

    How much ref. did you put in?  First statement sounded exactly lo on charge.  Need more info in list form.  Check sub-cooling if any and S/H.  Since you think bad compressor (I don't) Use scale and add 1 to 2 lbs.  Monitor your gauge pressure and S/H and Sub  cool.  Yes a compressor with bad valve will give you hi suction and lo head.  I know you think you are sure on this unit, but when you add ref. temps will tell it all so if you can run a test and document everything so we may help. 

    Mike T.
  • EddieGEddieG Member Posts: 150
    Need more info.....

    What type of metering device? Try unplugging outdoor fan, see if head pressure rises. How about indoor air flow? Your standing pressures when system off sound to low. What was compressor amp draws? Pumpdown test can't always be trusted, leaking service valve or reversing valve. Let system run for 10 min. place temperature clamp right on suction line at compressor and monitor. Kill power, if temp. reading spikes up immediately, valve is shot.
  • meplumbermeplumber Member Posts: 678
    Indoor air flow.

    Sounds like low indoor air flow to me. Eddie is right as is Mike. Unplug the condenser fan and watch your head pressure. I seriously doubt a bad compressor at the moment.

    Give us your readings and lets see if we can figure this out.
  • Paul_69Paul_69 Member Posts: 247

    i didnt get exact temps. recorded, but how can it be low indoor flow with high super heat, if it was low on chge would have high super heat, with both with low suction readings right? next time having troubles to share i will write all readings down. this customer wants new equipment anyways. he said he doesnt want to play and convert to 410a with new coil, line set, and condenser. air flow was moving good inside and as i said superheat was high not low, air was warm as was inside coil. couldnt compressor valves just be bad eneogh where it isnt pumping and thats why high and low pressures are low?
  • Paul_69Paul_69 Member Posts: 247
    guess what

    i went back to this job andguess what? the other unit at house was doing same thing as previous unit. now i said wait a minute cant be two with same symptoms right? wrong!! after racking my head thinking there might be wrong freon in unit, blockage bad or defective compressor etc.i found first floor condenser was controlled by 2nd floor tstat,and 2nd floor condenser was controlled by ist floor tstat. so when both were on at same time no problems. but if one was on when other was off the inside blower wasnt going!!that was giving me the previous readings posted.a electrician had run new low volt wires to each condenser and thats why it was screwing up because it was going to airhandlers that were not blowing unless the other one came on. make sense? holy cow. i was running inside and saying wow the blower is going good what is going on with these was **** backwards . today i said no way is two the same siuation without a common problem. so i went on a mission and had the blower going on on 2nd floor and turned on ist floor tstat and saw what i thought was ist floor condenser running nice and great performance outside, super heat, split etc. now i go into ist floor air handler and no performance. warm coil, no drop. i said to my son the heat is coming from somewhere to have good readings etc. on outside i said oh my god i run up to attic and its running superb at airhandler coil, swaeting etc, but  i only had ist floor tstat on! mystery solved. reverse wires on low vot at condensers and they ran like a top!even one at a time.condensers were not marked,freon piping was hidden in walls,and when i turned on the thermostats and saw compressors run i assumbed they were correct .but i was honest and got to the bottom of problems and was never satisfied with the other readings and was hesatint about replacing equipment without firm proof. thx for all the posts.i did two times say i think blower isnt going but when i ran in it was going. the problem is it was reversed and really screwed me up!!!!!!!!!!
  • don_9don_9 Member Posts: 395

    That was a pickle.funny how those hot attic add enough heat to the ducts and airhandler to keep the system from freezing with no airflow.I do find it odd tho you had  high superheat with low suction.Good job Paul at least you hung in there and found the problem.

    Did you troubleshoot yourself out of a new sale?

    I had a guy call me last night on some ductless split system that in his words are 25 years old.he said he done had four tech out from the home warranty company.They said the comp could be bad or its has a leak and could be low on freon.And the system is old and need replacing.

    I'm like ok and asked why are you wanting to pay me to come out and tell you the same-thing? i am like its 25 years old do yourself a favor and replace them.You will get a warranty the equipment will be more efficient and even better you don't have to put your life on hold waiting on the ac men all the time.

    I asked would you like me to come out and give you an estimate on new equipment?He like no i want to have it repair.I was like OK thanks but no thanks stick with the warranty company.

  • Paul_69Paul_69 Member Posts: 247
    no sale

    ya don, looks like he doesnt need stuff from what i saw yesterday with both running great.units are 12 to 13 years old but if they were not dead and he didnt want to upgrade unless it neededto be done. i will see how they work for a week and follow up with him. these are older people and he is battling cancer and they were so happy i found out they were able to be fixed.i easily could have sold them new unit. it is hot and they know nothing about how the equipment works.i really could use the money also but i wont do this to people. now if i didnt try again to solve problem i would have changed unit and if both were running again at same time it would have hid problem and i still would have problems after installing new units when one was running, how would i look!! i would have been in a jam for sure.lesson learned for sure.every so often you get these wacky calls that are not normal every day service calls that you troubleshoot find problem and fix.
  • meplumbermeplumber Member Posts: 678
    Great find Paul

    It cost you a sell, but Karma will come back to you. I guarantee it.

    I have had a few of the multi minisplits lately where my guys have crossed up the wires when they got them back to the condenser. Takes a few minutes to find it. They are now instructed to test them one at a time.

    Great find.
  • Empire_2Empire_2 Member Posts: 2,343
    Not related, but when the bell tolls....?

    This was a while ago.  Went on a service call, introduced myself, asked what the problem was.  She stated that the A/C was not working, was 3 years old and should be under warranty.  I wander down to the basement, yell for her to turn on the A/C.... Nothing happens.  Started taking a few tools out and Boom the A/C went on....Then off.  I asked her to turn it back on, she said she didn't touch the t-stat.  Quickly it does the same thing.  Come to find out someone had installed a new door bell and switch and when was in front of the furnace, someone rang the doorbell and the A/C came on...then off.  Now I've seen everything.  He tapped into the stat line for his power to the door bell.

    Mike T.
  • Paul_69Paul_69 Member Posts: 247
    ding dong

    very funny mike,just when you think you seen it all!
  • don_9don_9 Member Posts: 395

    Sorry guys I meant to say I found it odd that he had a high superheat reading with no airflow.In my earlier post i said  i found it odd he had a high superheat with a low suction.duh.

    Thought i should make that right before someone called me on it or i confused someone.Sorry gentlemen i will not let it happen
  • meplumbermeplumber Member Posts: 678
    We will let it slide this time Don.

    Mike, I had a tech with a similar occurrence several years ago. When the carpenters had installed the new front door, they picked up the tstat wire for the door bell. The door was installed in the summer. Call was for the boiler coming on and off irradically in the summer.

    Took him several hours to figure it out.
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