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View Full Version : High side pressure fluctuates on new system.



maxwell800xp
08-17-2012, 07:20 PM
I just installed a new Goodman 13SEER 2.5Ton R410a (scroll) fixed orifice system with new air handler. Correct oriface was installed. Out side temp is 93F indoor is 73F. Low side pressue fluctuated 132-136psi. Low side temp is 58.6F giving me a superheat of 17.4. Calculated super heat is 14. Not far off. The high side is fluctuating from 450-650psi. I have not seen this before. I can hear the compressor labor at the higher pressure. My boss said not to worry about it unless the customer calls. I think the compressor may be damaged by this high pressure. Any thoughts out there?

martyinlincoln
08-17-2012, 07:47 PM
Shouldn't have anywhere near that high of head pressure with 93 ambient. If you weighed in the correct charge then check for non condensables.

energy star
08-17-2012, 08:16 PM
Might as well get some parts in stock now.

SBKold
08-17-2012, 09:00 PM
You have a 5mm coil unit. You need to remove some.

socotech
08-17-2012, 09:33 PM
Sounds like noncondensables to me. Did you pull deep vacuum? Microns?

cavitech
08-17-2012, 10:07 PM
Balance the charge, all I install is Goodman and I've seen this more times than I can count.

Snapperhead
08-18-2012, 07:07 AM
Remove some and tell us what happens ....

Saturatedpsi
08-18-2012, 09:18 AM
For that OD temp, the head pressure should be around 375 psi. Measure subcooling and see if it's not way high.

jtrammel
08-18-2012, 09:49 AM
Overcharged

LKJoel
08-18-2012, 10:24 AM
Sounds like noncondensables to me. Did you pull deep vacuum? Microns?

I agree, first glance sounds like noncondensables

kw10925
08-18-2012, 09:09 PM
Not to sound stupid but from what i read he has a new 410a system and a new air handler,Shouldnt that be a txv not a fixed orifice.
and did he change the filter drier as well

Crazecodyk
08-18-2012, 09:26 PM
They ship systems with orifices and txvs. If was new system why wasn't the factory charge adequate?

SoFlaDave
08-18-2012, 10:38 PM
If its a microchannel condenser the charge will be very light for even the shortest runs and in general will hold almost 20% less than a comparable tube/fin system when fully charged.

LibertyTree
08-19-2012, 04:35 AM
If its a microchannel condenser the charge will be very light for even the shortest runs and in general will hold almost 20% less than a comparable tube/fin system when fully charged.
Goodman doesn't use Microchannel, but on their AC's they use a 5mm coil. Both are critical charge units (I think the 5mm is a bit more forgiving.) I'm putting my money on overcharge with a side of non-condensables.

drife678
08-19-2012, 05:52 PM
Goodman doesn't use Microchannel, but on their AC's they use a 5mm coil. Both are critical charge units (I think the 5mm is a bit more forgiving.) I'm putting my money on overcharge with a side of non-condensables.

non condensibles.

dna
08-19-2012, 07:28 PM
Sounds like non-connies also.

Oldschoolmetal
08-19-2012, 08:42 PM
I would say overcharged..

Shylton05
08-19-2012, 11:53 PM
Sounds like noncondensables. Recover the system, pull a good vacuum, and recharge. Your boss should be smacked for telling to not do anything unless the customer says something about the noise!

heresjohnnyb
08-20-2012, 07:38 AM
You have nitrogen mixed in with the 410. May have happened at the factory or with your leak test if you did one. Pull the charge in the system and be careful not to kill your recovery machine doing it:whistle::whistle:. you may have to resort to some diminimus to not damage your equipment.

LibertyTree
08-21-2012, 12:37 AM
You have nitrogen mixed in with the 410. May have happened at the factory or with your leak test if you did one. Pull the charge in the system and be careful not to kill your recovery machine doing it:whistle::whistle:. you may have to resort to some diminimus to not damage your equipment.
I read your post and it made me cringe... I just had one of my guy's install a Goodman dry R22 unit. I told him about 8 times that there is no refrigerant in the damn thing and that he needs to let the nitrogen out then pull a vac then charge. This dullard went ahead and pulled a vac then cracked the valves releasing all the nitrogen into the system then turned the unit on... He sat there for 2 hours like a dope trying to figure out why the suction side gauge was pegged out at "retard". I told him that he's the reason why it says "retard"... I went out there and heard the compressor being tortured to death.

drife678
08-21-2012, 07:40 AM
Same thing at my company. After I wasted around 15 pounds from two different systems, they finally sent a memo out to all our installers.who cant read anyway. Big sticker right.next to service valves charged with nitrogen, remove and pull vacum then charge.. Lol dont.they get it dry unit....lol

mgenius33
08-21-2012, 11:28 AM
I can hear the compressor labor at the higher pressure. My boss said not to worry about it unless the customer calls. I think the compressor may be damaged by this high pressure. Any thoughts out there?

I hope there are plenty of homeowners reading this post!
This is that guy who came in $1000 lower on a full system quote!
Now you know what you're paying for!

I hope your boss goes out of business for ruining my industry! Sorry about your luck. I would suggest finding someone else to work for. You are on a sinking ship!

Rodney28334
08-21-2012, 04:12 PM
Make sure the piston isnt clogged, but if it were your sh and sc shouldnt be in line. If it warms up any it will be bouncing off high limit.

Sicofthis
08-21-2012, 05:39 PM
There's an easy check for noncondensables get post count up and apply for pro.