Walk-In HELP!!!

[platinumfreeze]

I did a ****ty job explaining this the last time so here it is. I have a walk-in refrigerator that freezes intermittently. I've changed the t-stat and still does the same thing. I'm wondering if it the way the t-stat bulb is placed.
PLEASE HELP!!

[Gary]

I have a walk-in refrigerator that freezes intermittently.

I'm visualizing a walk-in refrigerator that has transformed the entire box into a huge block of ice. Or perhaps you are saying that the coil is frozen. Or maybe the lines are frozen. Or maybe there is frost on the ceiling... or maybe on the floor... or maybe something I haven't thought of is frozen?

[platinumfreeze]

It freezes the food intermittently.

[Gary]

Where is the thermostat bulb placed?

[platinumfreeze]

The original t-stat control was mounted inside the the walk-in and the bulb was not mounted, just hanging. When I replaced the t-stat I mounted the control on the outside about 10" right of the door and ran the cap tube through the walk-in wall and around the edge of the evap box. The bulb is mounted to the evap box but not touching the evaporator, its not in direct air flow from the 2 evaporator fans. I hope that describes it enough, I'll go to the restaurant and take a picture if you want. Thanx

[Gary]

The bulb should be sensing the air flowing into the coil... but not too close to the coil... kinda hanging in the air.

What are the settings on the thermostat... both setpoint and differential?

[platinumfreeze]

It's set at 52-44 F differential of 8 degrees. The owner says when he gets there in the morning all the vege's and meat are frozen and sometimes a few beers have busted.

[Gary]

Also, the cap tube must be above the sensing bulb. Mounting it upside down drives the liquid portion of the charge out of the bulb, into the cap tube, possibly even back into the control.

[platinumfreeze]

Is the control damaged permanently if that occurs? I'm going to relocate it tomorrow. Thanx

[Gary]

No, there is no permanent damage. Once the bulb is right side up and in a cool area the liquid will migrate back to the bulb.

[Gary]

Hopefully this will solve the problem, but if not you may need to move the control inside the walk-in.

[abet_meneses]

platinum freeze,
is the walk in chiller space has a walk in freezer door or has a partition panel for freezer?

regards,

[platinumfreeze]

No, just a 10'x10' walk-in refrigerator.

[nike123]

How are the goods arranged inside?

Does the air from the evaporator blows directly in to the frozen goods?

Does the goods who are not in direct path of the air also frozen?

What is TD of evaporator? What is the temperature of the air in and out of the evaporator. In the same time, what is the temperature near the termostat bulb?

Did you checked with thermometer correct function of the thermostat regardless of being new?

[Andy W]

I have had a few sticking contactors over the years causing the unit to run continiously.

[Toolman]

I have had a few sticking contactors over the years causing the unit to run continiously.

Yes that is a good point Andy makes .

Have you ever seen the unit cycle off via the Thermostat ?

Get rid of the old mechanical stat and fit a Danfoss EKC , Carel IR33 or Dixell and make sure you run these through
a mini contactor so the load doesnt go through control. They sya they can handle the amperage but they never do
in the long run .

[platinumfreeze]

Thanx for all the input!!! I used a number of suggestions. I repositioned the T-stat bulb, redirected the air flow and also changed the wiring around so the load from the compressor was not gong Through the T-stat.

I remember thinking about the contacts sticking in the T-stat, but I ruled it out because it was new and figured it was bulb placement. Anyway it's been working great and the temp is consistent all around the box. THANX AGAIN!!!!!

[The MG Pony]

Thank YOU for giving us an update! So few give the apretiation to say how the advice turned out. We love to hear of success