Replysounds like over charge. let out a few ounces at a time and take it to 10* sc.
Professional Member
3 ton 10seer condenser with micro channel. The pressures were good. 13deg subcooling. Calls for 10 to 12. Has expansion valve. R410. Ten minutes later the head went to almost 600 psi. The suction dove way down. The comp. Didnot go off on hps. Lasted less than a minute then pressures went normal. Im going back with more time tomorrow.
Professional Member*
sounds like over charge. let out a few ounces at a time and take it to 10* sc.
Global Moderator
There are no 10 seer, 410A micro channel condensers.Originally Posted by dave sulz
I agree with gravity - probably overcharged, and a good place to start your troubleshooting.
Every one of these units I have seen are suppose to have 10 degrees of subcooling, and your 13 degrees is too much. Remove a few ounces as gravity said, and see what happens.
Is this a new install, or one that many techs have tampered with?
Instead of learning the tricks of the trade, learn the trade.
Professional Member
The owner said it worked fine for a year and a half
Professional Member*
I sold a 13 SEER LuxAire/York with a TXV about 3 years ago. It wouldn't stay running. We needed to add a start kit.
They told me the problem but I don't remember what it was now.
Professional Member
An over charge doesnt make the suction gauge plumit and high side blast to 550 at the same time
Professional Member*
Don't know why. But it seems like your TXV stop feeding and that's why you see 550 PSIG (because the coil is too small to hold all the charge. My guess is OIL. I don't know why but these 410A system has a lot of oil comparing to those with R-22.
Another thing, you rather have a little lower subcool than spec and not over the spec subcool.
Professional Member*
restriction or overcharge. thats all i can think. i have never seen a TXV close shut and open back up like you are describing.
the restriction could have cleared itself when the pressure got so high. condenser coil could have oil logged to. hows the piping look?
Regular Guest
Ok this is what I want to know you installed this new 410A Condensor, what about the coil inside? What age is the that coil? Did you add the TXV or did it have a Flow rater? Just asking to understand more why you may be having this problem? What size is your line sets?
Professional Member
Were you charging liquid when it did this? Reason I ask is I got distracted for a second when charging a new install the other day. Squirted a little too much liquid in and all of a sudden $hit hit the fan. HP went through the roof and suction dropped. I pushed some oil out of the compressor which I think acted like a temporary restriction. I know this because I had quite a bit of oil in my suction line(more than quite a bit actually). Almost swallowed my tongue. I didnt overcharge I just went too fast. Scared the crap out of me. I watched for a bit for the head to come back down(it was still abnormally high), made sure I had plenty of superheat, went and did a call and came back. Head was still elevated but had come back down considerably and my suction was looking much higher too. Let it run until quitting time and it was purring. Topped off the charge and all is well.
As far as the hard start kit. All of Yorks newer TXV's are non bleed. The outdoor units will not have factory start capacitors, they are an add on and if you dont add it you will be returning to do so.
Professional Member*
I have seen this same problem with the York RTU with Micro Channels. I even posted about it. York Tech support told me to remove 8OZ from the factory charge. It has been working ever since. This RTU was working for 2 Years before this problem. I say over charged. Ask York what they recomend the charge to be cause the labels are too much for the microchannel condensers
Global Moderator
Here is another thought if removing some charge doesn't solve the problem, and you are thinking now that it might be a restriction.
These units, if I'm not mistaken, come with a LLFD installed inside the unit, does this one have a second LLFD on the outside of the unit?
I'm still leaning toward the overcharge though.
Instead of learning the tricks of the trade, learn the trade.
Professional Member*
Over charged...do some research on York micro-channel technology. The burp in the system is literally like a vapor lock in the condenser coil. Acts like a restriction, but then all of a sudden the thing farts and pressures drop to normal. Here is a few good York articles explaining the issue:
http://yorkcentraltechtalk.wordpress...ndenser-coils/
http://yorkcentraltechtalk.wordpress...unit-charging/
Professional Member*
I am thoroughly un-impressed with these coils., when used in a Coastal Area at least. Haven't run across many of them but of the few we've seen the coils leak and when changed under warranty the old coil fell apart, that is the line and fins separated from corrosion.
Professional Member*
Yep they don't have to be at the coast to fall apart like that either.
Professional Member*
The unit is over charged. The unit is using a non bleed txv. When the unit starts the suction pressure change causes the txv to open. If before this can happen, the unit goes off on hi head then you are overcharged. If the unit uses a recip compressor, it must have a hard start added. Charge the unit to between 4-8* of subcooling with 6* being most ideal for avoiding call backs on these types of problems. A good way to differentiate between a bad TXV and an overchage is to manually depress the contactor for a few seconds to see if the TXV opens and the pressures go down. If they do then remove charge 2-4 oz at a time until you are around 6* subcool. I see guys constantly replacing TXVs on these systems when the problem is simply an overchagre. No confirmation but i think that some of the issue with these units running fne and then all of a sudden exibiting these issues is oil in the condenser. Also the coils will be more demanding when it comes to keeping them clean. Just water or a non acidic coil cleaner will do the trick.
Professional Member*
It actually can on this type of system, the TXV doesn't have time to react before the unit goes off on hi head.
Professional Member
I went back and the guy left it on all day.comp. off on overload. Very hot. The standing press. Was 150 low and 265 hi. Pressure never equalized. I stayed for 45 min. Has spp6. Condenser tcgd36s41s3a evap g2fd036h17a. Johnstone said mc43c3xhi would now be used. I quoted txv/drier and new coil w/txv/drier. He'll let me know. Thanks for all the responces lm not a newbie. 20 plus yrs. A friend of a friend installed cond. Not me. He stopped tacking his call. Typical.
Professional Member
The equalizer tube on txv is installed correctly
Professional Member*
The pressures won't equalize - that's the point of a non-bleed txv and that tube is not an equalization port it is a port through which the TXV refrences the suction pressure. actually if you want to save yourself a head ache you can just put a piston in that coil. you aren't getting any seer boost with a txv the tcgd is 13seer builder's grade i always recomend pistons on these units to avoid the very problem that you are having.
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