Stop guessing.
Diagnose smarter.

That symptom set — compressor running, suction line barely cold — points to one of three things. Here's how to narrow it down fast:

1. Check your pressures first.
On 410A you'd expect suction around 115–125 PSI and discharge around 375–400 PSI at typical load. If suction is low (under 90) and discharge is also low, you're looking at a low charge or a restriction. If suction is low but discharge is normal or high, suspect a bad compressor valve.

2. Feel the liquid line temperature.
Should be warm — close to outdoor ambient. If it's cold or room temp, you've got a restriction upstream (TXV, filter drier, or king valve partially closed).

3. Check superheat at the suction.
If superheat is high (over 20°F), you're either low on charge or starving the metering device. If superheat is near zero and the line is still barely cold, bad compressor is likely.

What are your pressures reading?

That's a classic low charge profile. Both suction and discharge are depressed together — compressor is working but there's not enough refrigerant mass to build head pressure.

Before you add refrigerant: check for an obvious leak first. With 410A systems this low, something let go. Common spots on this kind of reading:

• Schrader valve cores (check both)
• Flare connections at the linesets
• Evaporator coil (especially if it's older)
• Service valve packing

Leak check, repair, then recover/recharge to manufacturer spec. Don't just top it off.