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Also check that indoor fan is on high speed

Dirty air filter equals low condenser air flow in heat mode

Originally Posted by jeffrey43

Well some of you were right it was over charged and had a filthy filter.

I haven't seen all there is to see, but I've never seen high head with residential systems caused by anything other than, too much refrigerant or too little condenser air. One or the other (or both) is always a safe bet.

Well some of you were right it was over charged and had a filthy filter. The HO didnt even know there was a filter to be changed. I showed it to them when I did the install but no recollection of it from them.

Thanks for all your help

I am pretty sure any good service technician knows that you charge a TXV system by suBcooling... And you charge a fixed orifice system by superheat..if you don't charge by that rule you will always have problems

hvacvegas the reason you are not having problems because you are installing them properly.. It is crucial that every unit is properly charged upon installation especially on heat pumps. All heat pumps should and must always use a TXV metering device and be charged by suBcooling method. R410A does not "lie" to your gauges for the first two hours, I don't know who came up with such a thing.. You must however allow the unit to run for at least 15 min before you begin making adjustmens on the charge... We are going to see more and more companies having problems with R410A systems because they are not like the old R22 units where you could charge them to beer can cold and it will work...

Originally Posted by philjafo

Goodman and this is the answer their technical advisor gave us. It is with txvs also. I have seen it with my own two eyes and yes I did check to make sure indoor conditions were the same. At install sh correct, two weeks later severely overcharged, not just a little. Maybe its not the refrigerant, maybe its something else that changes, all I know is that once we started weighing the charge in at install the problem went away. Just like goodmans rep said, so I had no reason to doubt him or research it further. I absolutely hate the idea that the direct measurements are inaccurate, but that's what works. I know a lot of guys on here install Goodman equipment, we can't be the only company that's had this problem

I've installed only (practically) goodman equitment for 8 years, and have never had this problem.

Originally Posted by philjafo

Goodman and this is the answer their technical advisor gave us. It is with txvs also. I have seen it with my own two eyes and yes I did check to make sure indoor conditions were the same. At install sh correct, two weeks later severely overcharged, not just a little. Maybe its not the refrigerant, maybe its something else that changes, all I know is that once we started weighing the charge in at install the problem went away. Just like goodmans rep said, so I had no reason to doubt him or research it further. I absolutely hate the idea that the direct measurements are inaccurate, but that's what works. I know a lot of guys on here install Goodman equipment, we can't be the only company that's had this problem

I've used Goodman(R410A) on swap outs and not changed the line set and had no idea of the line set length. Just did it by SH and SC. Haven't had to go back to any and adjust charge.

Originally Posted by philjafo

Goodman and this is the answer their technical advisor gave us. It is with txvs also. I have seen it with my own two eyes and yes I did check to make sure indoor conditions were the same. At install sh correct, two weeks later severely overcharged, not just a little. Maybe its not the refrigerant, maybe its something else that changes, all I know is that once we started weighing the charge in at install the problem went away. Just like goodmans rep said, so I had no reason to doubt him or research it further. I absolutely hate the idea that the direct measurements are inaccurate, but that's what works. I know a lot of guys on here install Goodman equipment, we can't be the only company that's had this problem

Never had this happen to me before, I weigh in the additional charge for line sets and let er rip. Haven't had a call back on a new install for charge. Have change many leaky Evaps pump Down, change coil, vacuum,open up, top off and havn't been back for charge. SC and SH works fine for me with 410. You do have to wait 15-20 min for it to stabilize but not 2hrs

Goodman and this is the answer their technical advisor gave us. It is with txvs also. I have seen it with my own two eyes and yes I did check to make sure indoor conditions were the same. At install sh correct, two weeks later severely overcharged, not just a little. Maybe its not the refrigerant, maybe its something else that changes, all I know is that once we started weighing the charge in at install the problem went away. Just like goodmans rep said, so I had no reason to doubt him or research it further. I absolutely hate the idea that the direct measurements are inaccurate, but that's what works. I know a lot of guys on here install Goodman equipment, we can't be the only company that's had this problem

Originally Posted by philjafo

I've never had a problem topping off a system like you say beenthere, even on evaporator coil replacements, only on New system installs, it was explained to me that 410a is a mixture of two refrigerants and something happens to it after the first few hours of runtime. I can't explain it any better but with new installs if they are set to sh sc we always end up going back, weighed in it works so I will continue to set them up the way that avoids callbacks. I would really appreciate it if someone could explain it but I'm not too worried about it

You were LIED to.

If it was true, then it would also happen on TXV systems.

What brand unit are you installing.

I've never had a problem topping off a system like you say beenthere, even on evaporator coil replacements, only on New system installs, it was explained to me that 410a is a mixture of two refrigerants and something happens to it after the first few hours of runtime. I can't explain it any better but with new installs if they are set to sh sc we always end up going back, weighed in it works so I will continue to set them up the way that avoids callbacks. I would really appreciate it if someone could explain it but I'm not too worried about it

Originally Posted by jeffrey43

I appriciate everyones input on this. I think its high head pressure possibly the charge is off and the filter has not been changed.

I'm going to take a stab in the dark, and say that you weighed this goodman in on startup.
Which would mean it's overcharged. Goodman is STILL overcharging their condensers from the factory. Unless I'm getting older stock. Who knows.
If you pull all your refrigerant out (or do a dry system), you can be on the money by weight. If you rely on the factory's 15' rule, your screwed.
Check your normal stuff. 2 month run time could be a filter.

I'm with beenthere on the gauges thing. Only time I've heard of that, is with microchannel package units. I think it was york that realeased that bulletin about their scrolls "losening up" after a few months of run time or something along those lines. If I'm confused, please enlighten me.

Still the idea 410a lying to you is confounded.

I appriciate everyones input on this. I think its high head pressure possibly the charge is off and the filter has not been changed.

Originally Posted by philjafo

Not trying to start an argument beenthere, it was just the easiest way to put what I was trying to say. When a 410 a unit fixed orifice is installed and charged according to sh, it will be correct and something happens to the refrigerant that changes the pressures and temperatures. Weighing the charge according to the manufacturer specs eliminates that problem.

You or the other techs were you work are doing something wrong then.

By what your saying. We can't go and find that a schrader was leaking, replace and and then top off charge by SH.

Which I and many other members of this board have done with no problem.

I have to agree, 410 can be touchier on charging. Last summer I had a trane with EEV, new system start up. Let it run 15-20min to stablize, both SC & SH were off, LIke 3SC, 35 SH. Added and waited, press, SC & SH got closer but still off, added more, waited, better but still not right. Houra & 45 min later we looked good. Left the job a little after 5 PM. got a call around 9PM no cooling. Went back out, grossly overcharged. Adjusted it down into a recovery tank to where it would run and told them I would come back the next moring to finish adjusting. Had that happen to one of my techs also.

The refrigerant does not change. Maybe your indoor conditions change.

Not trying to start an argument beenthere, it was just the easiest way to put what I was trying to say. When a 410 a unit fixed orifice is installed and charged according to sh, it will be correct and something happens to the refrigerant that changes the pressures and temperatures. Weighing the charge according to the manufacturer specs eliminates that problem.

Originally Posted by codgy

agree that weighing charge is the best option. never a callback.

Weighing in is best. But R410A doesn't "Lie" to your gauges for the first few hours.

agree that weighing charge is the best option. never a callback.