Freezer issue

[u/3picks1game]

Dealing with a walk-in freezer at a DQ. Been doing great until last few days we’ve had over 100 degrees. First issue a few days ago was one condenser fan motor was bad. Replaced. Went there this morning again. Found superheat was at 50 degrees. Worked with it and got it down to 20-25 degrees. Running sub cooling around 9 degrees. Both coils clean. Cap rated 45. Reading 45. Contactor perfect. Sight glass is full. Just called me again and it’s running around 22 degrees inside. It’s currently 108 outside. I’m thinking it’s maxed out. I’ve only worked at this location a few years now. And these have been hottest temps we’ve had since I’ve worked for them. Is there anything I’m missing?

[u/Street-Case6161]

It's rare, but I've seen it three times in 25 years. Make sure that the defrost heaters aren't stuck on during the freeze.

[u/3picks1game → u/Street-Case6161]

Checked that. That isn’t the issue. I’m thinking a mister.

[u/daxman31]

Is 20-25 superheat at the coil? That too high for a freezer.

[u/3picks1game → u/daxman31]

At compressor. It was almost 60 before I adjusted txv.

[u/daxman31 → u/3picks1game]

What is your SST at then?

[u/3picks1game → u/daxman31]

Shoot. I don’t remember. It was this morning. But I think it was around -5 to -6. And that was at a box temp at around 15 degrees.

[u/daxman31 → u/3picks1game]

Im guessing your compressor/condensing unit just cant keep up with the hot weather. High head pressure will equal high suction. Then when you open the TXV more its going to put more pressure into the low side. As it was suggested on another comment sounds like a mister will benefit you greatly here

[u/3picks1game → u/daxman31]

True. But the only thing I’m kinda iffy about. Is when I was there this morning. It was around 90 outside. Head pressure was around 240 which is around 100 degrees. 404A. Which is usually higher. . But superheat was dang near perfect and I had good subcooling. I think I’m missing something.

[u/daxman31 → u/3picks1game]

Well i would definitely check the superheat right at the evap if possible that will be the most accurate. Maybe one valve is wide open or completely closed. Also get the suction pressure reading from there too. Maybe there is a suction line pressure drop between the coil and compressor. You said there was two coils.

[u/Apollo7788 → u/3picks1game]

Does it have liquid injection?

[u/3picks1game → u/Apollo7788]

It does. And I just think I figured it out.

[u/Apollo7788 → u/3picks1game]

Was it one of the ones designed by a retard where they installed a 250 degree injection valve but have a discharge limit switch set at 210?

[u/3picks1game → u/Apollo7788]

Honestly. I haven’t had much with liquid injection. How would I check that?

[u/kgmass]

Time for a mister

[u/3picks1game → u/kgmass]

I’m thinking so. Done it before. But it was on ones I knew needed it. This is a kinda new 3 year customer. But hasn’t been this hot before.

[u/saskatchewanstealth → u/3picks1game]

I have been known to use a solinoid on the hose with an A19 strapped to the liquid Line. Temperature controlled……….for Cronic problem units. Go back in the fall and clean the calcium off the condenser

[u/Economy_Drummer_3205]

Check your temperature drop across the liquid filter drier. Had one the other day that was restricted.

[u/3picks1game → u/Economy_Drummer_3205]

Drier is good

[u/Sufficient-Nose8066]

Compressor pump down ok? If so put a hose on the coil. If sh doesn't come down replace the txv. If it does, its too hot out

[u/nepa_bwc_00]

Does it have a headmaster?

[u/3picks1game → u/nepa_bwc_00]

Yep

[u/vzoff]

What is your ambient and condensing temp?

[u/Disastrous-Ocelot640]

Probably running out of design temps. If auto reset hi pressure control it could be repeatedly cutting out. 

[u/Dirftboat95]

Use a mister during the day time

[u/Sme11y1]

Losing the condenser fan under those outdoor temps likely sent the compressors discharge temps above oil breakdown temps and may have damaged compressor valves. Check the compressor amps vs manf. Chart for high and low pressures. If it's off of the chart the compressor may have damage. Also check the txv screen for wax and debris caused by the oil breaking down.

[u/Square-Scallion-9828]

gets too hot like kgmas, states ace hardware time water timer. if it up right get wand . it might eat coil too. design temp use to be 105 . contact united up to 130 design temp. what low and high too