SMAN4 and Charging Jacket video by Rich Mcfarland

[RussellHarju]

Here's a video on the SMAN4 of Rich, Fieldpiece's technical trainer, showing you the SMAN4 and charging jacket (S365)

[itsiceman]

So what was wrong with the unit?

[mark beiser]

With the indoor conditions shown in the video, there isn't enough load on the evaporator coil to accurately evaluate the refrigerant charge, or the performance of the system.

[FPTraining]

So what was wrong with the unit?

Actually there are a number of things wrong with this unit. It's dirty for one and the charge is off for another. However, the purpose of the video was to show you how to use the SMAN4 and the wireless capabilities, not how to fix or service an air conditioning unit. I also wanted to show how to use the Charging Jacket. You can only use the Charging Jacket with a TXV system so you must check by using the subcool method.
I want to point out that there is enough load to accurately evaluate the refrigerant charge and the performance of the system. The actual load can be thought out as "refrigeration 101". If we only think that it must be 70 degrees in the indoor unit then we would never be able to charge a refrigeration unit correctly. It's not certainly not 70 in my refrigerator nor is it warm in any refrigeration unit in any of the grocery stores that I visit. This system uses a TXV. So charging it according to the basics in "Subcooling" is easy done using the Charging Jacket.
Watch this video on the Charging Jacket



"Integrity - Doing the right thing when nobody is watching"

[hvac5646]

With the indoor conditions shown in the video, there isn't enough load on the evaporator coil to accurately evaluate the refrigerant charge, or the performance of the system.

HMMM...is that singed flesh I smell coming from your direction Mr.Beiser?

[jnsrose]

This is where I run into trouble when I do cold whether installations and start ups. If I were running that system in a low ambient condition for a data room wouldn't I worry about it freezing with such a low suction? Even with a low ambient kit the suction always seems to be low. Normally I weigh it in and check when it gets warmer but we all know sometimes we just do not get back. Would be nice to know that if I do not get back on time it will run ok.

[FPTraining]

This is where I run into trouble when I do cold whether installations and start ups. If I were running that system in a low ambient condition for a data room wouldn't I worry about it freezing with such a low suction? Even with a low ambient kit the suction always seems to be low. Normally I weigh it in and check when it gets warmer but we all know sometimes we just do not get back. Would be nice to know that if I do not get back on time it will run ok.

Hi jnsrose,
This is the beauty of the Charging Jacket. Since we are not blocking off the air going through the condenser, we are not starving it. We adjust the Charging Jacket to where the difference between the suction line and liquid line pressures are between 100 to 145 psig on R-22 and 160 to 220 psig on R-410a. Tightening the top of the Jacket causes the head pressure to rise and raises the higher liquid line temperature as well. This also affects the low side but only slightly. This keeps the suction line temperature above freezing. Because the pressures are higher, the vapor line and liquid line Saturated temperatures are also higher. Since the TXV controls the amount of refrigerant released into the coil the coil does not freeze up. The Charging Jacket works beautifully. It would be a valuable addition to your tool collection.

[hvac5646]

This is where I run into trouble when I do cold whether installations and start ups. If I were running that system in a low ambient condition for a data room wouldn't I worry about it freezing with such a low suction? Even with a low ambient kit the suction always seems to be low. Normally I weigh it in and check when it gets warmer but we all know sometimes we just do not get back. Would be nice to know that if I do not get back on time it will run ok.

How about a busy AC c/c schedule in mild spring weather?

Also there are plenty of occasions we have been slammed during hot summer months and we get a cold snap making system diagnosis difficult.

Refer techs have been doing variations of condenser blocking since air cooled application have existed.


Ever hear of a condenser fan cycling control on a refer system or motorized louvers that limit condenser airflow on cold days?

[FPTraining]

This is where I run into trouble when I do cold whether installations and start ups. If I were running that system in a low ambient condition for a data room wouldn't I worry about it freezing with such a low suction? Even with a low ambient kit the suction always seems to be low. Normally I weigh it in and check when it gets warmer but we all know sometimes we just do not get back. Would be nice to know that if I do not get back on time it will run ok.

jnsrose,
Also, a quick note. The system that I was using had a low ambient kit on it. Once I adjusted the Jacket I was able to keep the fan running on the unit. (raising the pressures). Also, it was 39 to 41 degrees outside!

[jnsrose]

Thanks for the quick reply. So the trick then is to get the separation between the high and low side? Are we still looking for the same subcool as warmer temps or are we looking for something a little lower?

[FPTraining]

Thanks for the quick reply. So the trick then is to get the separation between the high and low side? Are we still looking for the same subcool as warmer temps or are we looking for something a little lower?

Yes, The subcool would be the same target range.

[kangaroogod]

Waiting for that gently used sman3 trade in program

[itsiceman]

jnsrose,
Also, a quick note. The system that I was using had a low ambient kit on it. Once I adjusted the Jacket I was able to keep the fan running on the unit. (raising the pressures). Also, it was 39 to 41 degrees outside!

At that temp difference between liquid temp and ODA I would be suspect of the clamp reading you took Rich. Even testo recommends not using clamps in a situation like this. If you do it again you might be surprised to find your SC might be closer to what you were looking for