Results 51 to 100 of 166
Thread: low high-side pressure, help
-
05-07-2009, 06:56 AM #51
Re: low high-side pressure, help
there is no other high side tap
-
05-07-2009, 07:00 AM #52
Re: low high-side pressure, help
there is no other tap in the high side
-
05-07-2009, 07:13 AM #53
Re: low high-side pressure, help
Ok... then we have no choice but to trust the high side pressure measurement at the shutoff tap.
-
05-07-2009, 07:18 AM #54
Re: low high-side pressure, help
-
05-07-2009, 07:58 PM #55
Re: low high-side pressure, help
hi
is the unit is enough for the area coverd more detail pls
size of both orifices &u fitted with o ring&right direction
did condensing unit match air handling
more detail pls
-
06-07-2009, 03:01 AM #56
Re: low high-side pressure, help
suction line= 56f
liquid line=93f
low side=85psi
high side=200psi
condensor air in=82f
condensor air out=94
evap air in=77f
evap air out=59f
-
06-07-2009, 03:05 AM #57
Re: low high-side pressure, help
its a 3 ton goodman heat pump with matching air handler (both brand new).
its in a 900sq ft mobile home (with a lot if insulation).
the indoor orfice is a .82 and the outdoor orfice is a .55
both are in correctly and workin correctly
-
06-07-2009, 03:48 AM #58
Re: low high-side pressure, help
The .082 orifice is too large and is overloading the system. You need to switch to the .078 and then take a new set of readings.
Last edited by Gary; 06-07-2009 at 03:58 AM.
-
06-07-2009, 03:55 AM #59
Re: low high-side pressure, help
i know the orfice is too large but when i put the .78 in, the vent temp rose 8f
-
06-07-2009, 04:00 AM #60
Re: low high-side pressure, help
We need to get everything in balance. And at this point the orifice is too large.
-
06-07-2009, 04:06 AM #61
Re: low high-side pressure, help
ok ill put it back in but how will i get the temp down
how cold can i make it get?
-
06-07-2009, 04:09 AM #62
Re: low high-side pressure, help
am i expecting too much from this unit? because i really expected to see temps in the 40's.
-
06-07-2009, 04:21 AM #63
Re: low high-side pressure, help
it would seem that my understanding of how the system works is wrong, so what directly determinds how cold the coil gets?
-
06-07-2009, 04:28 AM #64
Re: low high-side pressure, help
Planning on turning your mobile home into a refrigerator?
-
06-07-2009, 04:29 AM #65
Re: low high-side pressure, help
Once we get the system in balance the next step will be to reduce the blower speed.
-
06-07-2009, 04:36 AM #66
Re: low high-side pressure, help
well kinda, i just want it to cycle during the day instead of running all the time. i keep the stat set on 70f, during the day it get up to about 82 of 83. when night falls, it takes it until 2am to bring it back down to 70.
i would have said that it was an insulation problem, but i rebuilt the house last year and completely packed every wall with styrofoam and fiberglass insulation then sealed the outside with thermoply before putting the siding back on. also if it were an insulation problem, i would figure it would recover fast at night or during the rain but it dont. and im trying to reduce my light bill from $400.
-
06-07-2009, 04:46 AM #67
Re: low high-side pressure, help
-
06-07-2009, 04:52 AM #68
Re: low high-side pressure, help
i couldnt agree more. ive never had this much trouble. ive always just charged a system to 72psi on the low side and it worked but like i said i havent done a whole lot of it.
-
06-07-2009, 05:14 AM #69
Re: low high-side pressure, help
-
06-07-2009, 05:16 AM #70
Re: low high-side pressure, help
BTW, right now you have 6F superheat, which means the system is overcharged. I clearly remember saying charge it to 15F superheat.
-
06-07-2009, 05:19 AM #71
Re: low high-side pressure, help
well maybe before this is all said and done, ill know the correct way. its sure been a learning experiance.
-
06-07-2009, 05:30 AM #72
Re: low high-side pressure, help
You might want to read through this thread:
http://www.refrigeration-engineer.co...ad.php?t=19701
-
06-07-2009, 08:27 PM #73
Re: low high-side pressure, help
hi
ur orifice size should be 065 indoor&o70 outside
-
07-07-2009, 02:06 AM #74
Re: low high-side pressure, help
ok i put the .78 back in and reset it and set the evap blower to low(from medium)
suction line=62f
liquid line=88f
lowside=80psi
highside=190psi
condensor in=79f
condensor out=89f
evap in=76f
evap out=60f
-
07-07-2009, 02:13 AM #75
Re: low high-side pressure, help
the .78 came with the air handler and the .58 was factory installed in the condensor. from all the experiments ive tried, when i install a smaller orifice, the vent temp rises. my only explination is that when i install a smaller orifice, it restricts the refrigerant flow too much and cant keep up with the coil. but i could be wrong.
-
07-07-2009, 03:20 AM #76
Re: low high-side pressure, help
With suction pressure that high the discharge pressure should be much higher. I'm thinking you may have an inefficient compressor.
Close the suction line shutoff valve and see if the compressor will pump down into a vacuum.
-
07-07-2009, 03:25 AM #77
Re: low high-side pressure, help
what would cause the compressor to be inefficient? and what would cause two of them to be? like i said before, this is the second system and both of them act the exact same way. i have examined both refrigerant lines inside and out and both are fine and restriction free.
-
07-07-2009, 03:50 AM #78
Re: low high-side pressure, help
um not very well. it pulled it to a 8inhg vacuum. is that enough? or could it be the reversing valve leaking? i have questioned the reversing valve all along but i dont know how to check it.
it doesnt seem to have much efficientcy in heat mode either but that could be a compressor too, right?
-
07-07-2009, 03:59 AM #79
Re: low high-side pressure, help
I found a piston kit chart. Let's see if we can find the official right size:
http://site.famousparts.com/goodman/PDF/PKC-00U.pdf
-
07-07-2009, 04:15 AM #80
Re: low high-side pressure, help
the condensor is a model # gsh130361bb
the air handler is a model#
adpf304216ba
i couldnt find the exact app for this unit in the charts.
-
07-07-2009, 04:31 AM #81
Re: low high-side pressure, help
oh i dont know if it matters, but whan i closed the suction shut-off valve, the high side pressure DID NOT rise.
-
07-07-2009, 04:33 AM #82
Re: low high-side pressure, help
Is there a model# on the coil?
-
07-07-2009, 04:34 AM #83
Re: low high-side pressure, help
-
07-07-2009, 04:35 AM #84
Re: low high-side pressure, help
which coil? but probly not there is not alot of id numbers on it
-
07-07-2009, 04:36 AM #85
Re: low high-side pressure, help
not much of a vacuum, 8 inhg
-
07-07-2009, 04:49 AM #86
Re: low high-side pressure, help
-
07-07-2009, 05:18 AM #87
Re: low high-side pressure, help
-
07-07-2009, 05:24 AM #88
Re: low high-side pressure, help
i cant find any other numbers, so what do u think about the vacuum and pressure?
-
07-07-2009, 05:27 AM #89
Re: low high-side pressure, help
i was told that the air handler was built to range from a 2 1/2 ton -3 1/2 ton, making it a good candiate for my 3 ton condensor
-
07-07-2009, 05:42 PM #90
Re: low high-side pressure, help
I am not ready to blame the compressor just yet. We need to get the right orifice in there and see what the temps/pressures tell us.
The .078 is just too large, so we can assume that the coil is not 3 1/2 ton.
Unless you can find the btu rating for the coil we will just have to keep changing orifices.
I want to see that suction pressure down around 70 psi (or a little less) with about 15F coil outlet superheat.Last edited by Gary; 07-07-2009 at 05:47 PM.
-
07-07-2009, 11:41 PM #91
Re: low high-side pressure, help
well before i knew about the superheat method, i was setting the suction pressure at 70psi or little below, and when i put in smaller orifices(trying to raise the head pressure) i would loose a significant amont of efientcy. wich is how i ended up with the .82 orfice, the gave me the coldest vent temp.
it still really concerns me, that when i shut off the suction valve completly, the high side didnt change but the low side came down to a small vacuum. before i blamed the compressor, i would question the reversing valve, but i dont know how to check it.
-
08-07-2009, 12:09 AM #92
Re: low high-side pressure, help
You keerp mentioning the vent temp as if it were important.
-
08-07-2009, 12:43 AM #93
Re: low high-side pressure, help
if it dont blow cold then whats the point?
-
08-07-2009, 12:44 AM #94
Re: low high-side pressure, help
60f just isnt cold
-
08-07-2009, 01:33 AM #95
Re: low high-side pressure, help
-
08-07-2009, 02:29 AM #96
Re: low high-side pressure, help
call it whatever you like but the whole fact of the matter is that it cant transfer heat if it cant make heat, and with a head pressure of 180psi, it cant make heat. and when i close off the suction line and it still dont raise the head pressure, nothing will no matter how many orifices i throw at it.
-
08-07-2009, 03:02 AM #97
Re: low high-side pressure, help
-
08-07-2009, 03:12 AM #98
Re: low high-side pressure, help
Did you try another orifice today?
-
08-07-2009, 03:27 AM #99
Re: low high-side pressure, help
no i didnt have a chance, but i would expect the pressure to rise since the refrigerant has nowhere to go, it would be compressed in the coil, hense the pressure should skyrocket.
-
08-07-2009, 03:31 AM #100
Re: low high-side pressure, help
the only other orifice i have is a .73, but when i installed it before it acted like it had too much restriction to flood the coil with enough refrigerant to keep it cool.
Similar Threads
-
9 superheat & subcooling scenarios
By nike123 in forum FundamentalsReplies: 39Last Post: 19-07-2011, 03:16 AM -
High discharge temp
By paul_h in forum Air ConditioningReplies: 48Last Post: 06-05-2009, 11:10 AM -
Capillary Tube Characteristics
By Chef in forum FundamentalsReplies: 9Last Post: 10-03-2009, 01:03 PM -
High Pressure Freezing
By mattynige in forum New TechnologiesReplies: 9Last Post: 19-06-2008, 02:03 PM -
discharge pressure too high
By zahar in forum Trouble ShootingReplies: 7Last Post: 16-02-2008, 08:58 PM