Cooler Weather and Warm Walk-In!

Walk in cooler with a daily temperature document
By Pat Finley – Master Certified Lead Technician

Tech Tip – As colder temps happen, your commercial cooler/freezer may struggle to keep up.

Have you noticed your commercial walk-in cooler/freezer temperature is warm in the morning but as it heats up outside, it begins to preform normally? This is due to the headmaster valve in your condensing unit outside. The headmaster valve’s job is to keep a certain pressure of refrigerant in your system. This ensures it operates properly in colder ambient conditions.

When it gets colder, your commercial walk-in freezer requires more refrigerant to maintain proper operation. The excess refrigerant “stacks up” or is in the condensing unit outside. This happens due to colder temperatures and the refrigerant condenses back into a liquid easier. The downside, you must maintain a certain pressure to ensure system efficiency. You must have a proper pressure drop across the thermal expansion valve, or TEV, in your evaporator. The headmaster valve helps maintain the pressure by allowing hot gas to bypass the condenser coil and keep the system pressure up to proper operating ranges. This allows your system to operate normally.

The downside is, this takes more refrigerant. The excess refrigerant backs up as a liquid in your condensing coil. If your system is low, this is when it will show. Your first sign that you may have an issue with the proper refrigerant charge is warm temperatures in the morning, but once it starts to warm up outside, you cooler/freezer begin to act normally.

If you start to notice this, it may be an indication or a precursor to a bigger problem in the future. The most likely indication is that your system may in fact be low on refrigerant. This could be due to a leak, or the system wasn’t properly charged to begin with. If this is left unchecked the unit simply will not be able to keep up and there will be a risk of food spoilage.

If you have any doubts your commercial cooler or freezer may need repair, please schedule your local service company out to verify for you. You never know, it could save you thousands of dollars in both repair and food costs.

To schedule commercial freezer/cooler repair with your nearest General Parts Group branch please call (888) 498-1238 or book on-line here.

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