Unit Icing up

[Snow23]

I have a Goodman CPLE36-1 condenser(heat pump) paired with a AR36-1 air handler with coil. Unit started icing up. Another tech replaced the compressor, but the unit is running the same.

R22 System
Suction Pressure 65
Discharge Pressure 150
Suction Line Temp 68F
Discharge Line Temp 90F

I also found in cooling that the discharge line into the reversing valve is 112f and the outlet is 82F. The suction in is 63F and out is 63F. To me it seems to obviously to be a restriction in the reversing valve but I can not find any source confirming my suspicion.

[pecmsg]

What’s the CFM’s?
What’s your SH & SC?

How does a reversing valve get restricted?

[Bazooka Joe]

Believe Goodman put driers even in that model number years, if so did the Tech at least replace or removed it from the outdoor unit.

What was the justification for replacing a compressor if indoor coil was icing?

Indoor coil clean.

What where your pressure reading and temperature difference when in heat mode?

What was the OD temperature when you got the 150 PSI head pressure in cool mode, as that's certainly low.

Metering device at ID coil what piston/TXV

Odd that the temperature drop across the discharge side across RV has a big differential but suction is OK

[Snow23]

Haven't checked cfm, rookie move, but the indoor coil and fan blades are clean. SH 30F and SC 7F.

[BNME8EZ]

I am confused!

How does one condemn a compressor on a unit that is having freezing issues? My cheat sheet says freeze ups are caused be low air flow or low refrigerant flow, without going into much detail. Low refrigerant flow from a bad compressor would not typically freeze a coil.

[Snow23]

Driers are new

Compressor replaced because the tech believed in had weak/bad valves

Didnt check in heat, another rookie mistake

OD temp 75F

piston metering device. Previous tech checked both orifices ,one at evaporator and another at condenser, for restriction.

The temp drop across RV on the discharge but no change on the suction is why I think it has a restiction.

[Snow23]

Honestly dont know. I'll have to check the cfms and take measurements in heat mode and see if I can figure out why the tech condemned.

[BNME8EZ]

Weak valves will raise the suction pressure so it becomes very hard to have a freeze up with bad valves. Your 30 SH/7 SC is the clue you need to check into.

[CircusEnvy]

Do you have a temperature drop? What are the dimensions of the supply and return trunks? Piston size?

If you’re going back, take static pressure too.


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[shellkamp]

I am confused!

How does one condemn a compressor on a unit that is having freezing issues? My cheat sheet says freeze ups are caused be low air flow or low refrigerant flow, without going into much detail. Low refrigerant flow from a bad compressor would not typically freeze a coil.

You must not have the updated cheat sheet.

Sent from my Moto Z (2) using Tapatalk

[Bazooka Joe]

I have the CPLJ model, with a discharge muffler and looked up the CPLE model and it shows a discharge muffler also. When you checked the RV temperature difference where you approx. 4"-6" away from the RV body on both sides on the discharge side and downstream of the muffler ( if muffler is still there ) and 4"-6" away from the valve body on the suction side? I have issues with the wide temperature differential on the discharge side but the suction is OK. If at worst case it's not shifting 100% then your suction should have a bigger differential.

If that temperature of that discharge line downstream of the RV is only 82 degrees ( cooling mode ) and if it's 82 in heating ( reason why you need to check heat mode ) then the Heat side will not work.

You can also wire the RV to manually shift yourself from cool/heat and vise versa in front of you. You have the low voltage right there.

If you get back to the job site check in heat mode taking accurate temperature readings with accurate probe secured to the RV lines 4"-6" away from body. Run unit for at least 5+ minutes before taking reading. What are you using to take those readings?

Put in heat mode then touch vapor line by OD unit. At 75 degree OD temperature you shouldn't be able to touch line.

Lastly the 150 PSI head pressure is quite low at 75 degree OD temperature. May want to partially cover OD coil to see if pressures rise.

How did he charge it? Weight method, superheat?

[BNME8EZ]

You must not have the updated cheat sheet.

Sent from my Moto Z (2) using Tapatalk

Send me the new one and I will break out the decoder ring.

[beenthere]

What was the indoor wetbulb. How long is the line set.

Recover charge and see how much it has in it, and if it adds up to factory charge plus what the line set requires.

[garyed]

My guess is the guy who changed the compressor because the system was freezing up, doesn't know how to charge the system correctly either.

[pecmsg]

My guess is the guy who changed the compressor because the system was freezing up, doesn't know how to charge the system correctly either.

Or change s compressor!

[Snow23]

UPDATE

Static Pressure is .2inwc but duct work was clearly added on in the past and incorrectly
Actual charge is 6.5 lbs Factory Charge is 6.4
Line set is 30ft
Outdoor Ambient 85F

IN COOLING
Indoor delta T 20F
Suction Pressure 65psi=38F
Suction Line Temp 62F
Superheat 24F
Discharge Pressure 155psi=85F
Discharge Line Temp 84F
Subcool 1F

IN HEATING
Indoor delta T 35F
Suction Pressure n/a due to second service valve being removed for unknown reasons
Suction Line Temp 73F
Superheat n/a
Discharge Pressure 275psi=125F
Discharge Line Temp n/a
Subcool n/a

Reversing Valve In Heat
Discharge in 178F
Discharge out 148F
Suction in 72F
Suction out 73F

Muffler before the reversing valve also removed for unknown reasons

[Bazooka Joe]

The CPLE brochere ( readily available online ) says the data plate charge is correct for 15' of correctly sized lineset and a matching indoor coil. Being a old unit, the weight method IMO was a justified way of charging...with that in mind you have 30' of lineset so taking .60-.62 ounces of liquid line for each feet above the initial 15' gives you 9.15 ounces, so to me your 8 ounces under charged IMO...for starters.

Still way low on head pressure @85 degree OD temperature, should be at least 210-225 ( cool mode ) give or take...with a 10 SEER UNIT.

You sure there's a ID piston in that unit?

Seems like with a new compressor it would be pumping OK but there is no resistance ( metering device ) to slow the flow of refrigerant with that low a head pressure.

[heatingman]

UPDATE

Static Pressure is .2inwc but duct work was clearly added on in the past and incorrectly
Actual charge is 6.5 lbs Factory Charge is 6.4
Line set is 30ft
Outdoor Ambient 85F

IN COOLING
Indoor delta T 20F
Suction Pressure 65psi=38F
Suction Line Temp 62F
Superheat 24F
Discharge Pressure 155psi=85F
Discharge Line Temp 84F
Subcool 1F

IN HEATING
Indoor delta T 35F
Suction Pressure n/a due to second service valve being removed for unknown reasons
Suction Line Temp 73F
Superheat n/a
Discharge Pressure 275psi=125F
Discharge Line Temp n/a
Subcool n/a

Reversing Valve In Heat
Discharge in 178F
Discharge out 148F
Suction in 72F
Suction out 73F

Muffler before the reversing valve also removed for unknown reasons

Amperage will help tell you if there is a restriction or not at the RV.

Since its vapor at the RV - temp drop does not mean alot.

Seems to me, your just low on gas.

But you need to plot the Target SH to know for sure.




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[garyed]

UPDATE

Static Pressure is .2inwc but duct work was clearly added on in the past and incorrectly
Actual charge is 6.5 lbs Factory Charge is 6.4
Line set is 30ft
Outdoor Ambient 85F

IN COOLING
Indoor delta T 20F
Suction Pressure 65psi=38F
Suction Line Temp 62F
Superheat 24F
Discharge Pressure 155psi=85F
Discharge Line Temp 84F
Subcool 1F

IN HEATING
Indoor delta T 35F
Suction Pressure n/a due to second service valve being removed for unknown reasons
Suction Line Temp 73F
Superheat n/a
Discharge Pressure 275psi=125F
Discharge Line Temp n/a
Subcool n/a

Reversing Valve In Heat
Discharge in 178F
Discharge out 148F
Suction in 72F
Suction out 73F

Muffler before the reversing valve also removed for unknown reasons

It would be helpful if you gave us at least the indoor dry bulb. The wetbulb would be good too because it would give a better idea of
what superheat to expect. At this point though the numbers just look like you're a little low on gas. Your delta T looks fine & so does the static pressure. If you had any serious airflow problems you would have a lot higher discharge than 275psi. Even with good airflow I would expect around 350psi at 80* OA in heat mode which is another indication of low charge. There's also the possibility that the instruments where you're getting all the readings are not calibrated properly. Either way I don't see any serious problem at this point & no reason to be changing any more parts.

[pecmsg]

UPDATE

Static Pressure is .2inwc but duct work was clearly added on in the past and incorrectly
Actual charge is 6.5 lbs Factory Charge is 6.4
Line set is 30ft
Outdoor Ambient 85F

IN COOLING
Indoor delta T 20F
Suction Pressure 65psi=38F
Suction Line Temp 62F
Superheat 24F
Discharge Pressure 155psi=85F
Discharge Line Temp 84F
Subcool 1F

IN HEATING
Indoor delta T 35F
Suction Pressure n/a due to second service valve being removed for unknown reasons
Suction Line Temp 73F
Superheat n/a
Discharge Pressure 275psi=125F
Discharge Line Temp n/a
Subcool n/a

Reversing Valve In Heat
Discharge in 178F
Discharge out 148F
Suction in 72F
Suction out 73F

Muffler before the reversing valve also removed for unknown reasons

It ran long enough in heat with 85°F ambient to get readings?