Williams Bar Fridge Not Working in Sydney — Temperature Board Relay Failure Diagnosed and Fixed on the Same Visit

A bar fridge that stops working is not something a hospitality venue can leave for days. The stock inside is needed for service, and waiting for a manufacturer part to arrive means downtime, lost product, and disruption to the business.

This Williams bar fridge had stopped completely. No cooling, no response at all. We diagnosed the fault, repaired it with compatible parts, and had the unit back in operation — all in a single visit.

What We Found When We Arrived

The unit was completely non-operational when we arrived on site. No cooling, no response from the control system. Nothing.

The first step in a situation like this is to determine whether the fault is electrical or mechanical. This matters because the repair pathway is very different depending on the cause. A refrigerant or compressor fault is handled differently from an electrical board fault.

Testing pointed clearly to the control board. Specifically, the main relay on the temperature control board had failed.

What Is a Relay and Why Does It Fail?

A relay is an electromechanical switch on the control board. Its job is to send power to the compressor when the thermostat calls for cooling, and to cut that power when the set temperature is reached.

Every time the fridge calls for cooling, the relay closes. Every time the temperature is reached, the relay opens. Over the life of a commercial refrigeration unit, this happens thousands of times. The contact surfaces inside the relay gradually develop damage from repeated switching, and eventually the relay loses its ability to make reliable contact.

When a relay fails completely, it usually does one of two things. It either fails open — meaning the compressor can never be switched on — or it fails closed — meaning the compressor runs continuously without stopping.

In this case, the relay had failed open. The control board could not send power to the compressor. The result was a unit that appeared completely dead, with no obvious external sign to separate this from a more serious mechanical failure.

Why This Did Not Require a Full Board Replacement

When a control board fault is identified, there are two options. Replace the relay, or replace the entire board.

A full board replacement for a commercial refrigeration unit often means sourcing a proprietary part directly from the manufacturer. That takes time and costs significantly more than replacing the individual component that actually failed.

The relay itself is an industry-standard electronic part. Compatible replacement relays are available across multiple suppliers and can be carried on a well-stocked service van. In this case, the board itself was in good condition. Only the relay had failed. Replacing the board would have been unnecessary and more expensive for the client.

Replacing a compatible relay is not a workaround. It is the correct repair when the failed component matches the original specification and the rest of the board is functional.

What We Did to Fix It

Here is exactly what the repair involved:

Identified and removed the failed relay from the temperature control board
Fitted a compatible replacement relay that matched the original electrical specifications
Inspected and rewired the connections at the repair point to make sure everything was correctly connected to the new component
Reset and calibrated the control board to the correct operating parameters for the unit
Ran the fridge through a full operating cycle to confirm the compressor was responding correctly and temperatures were stabilising as expected

The unit was fully operational by the end of the visit.

What This Means for Venues With Commercial Bar Fridges

A bar fridge or undercounter fridge that appears to have stopped completely is not automatically a unit that needs to be replaced. In many cases, the fault is a single component — a relay, a thermostat, a sensor — that can be diagnosed and replaced on the same visit.

The key is getting the right diagnosis first. Assuming a unit needs a full board replacement, or worse a full unit replacement, without testing the individual components can lead to unnecessary costs.

A component-level diagnosis is always the right starting point.

Williams Commercial Refrigeration Repairs in Sydney

BM Refrigeration services and repairs Williams commercial refrigeration equipment and all other commercial refrigeration brands across Sydney CBD and the greater Sydney area.

We diagnose and repair electrical and control board faults — including relay failures, thermostat faults, and sensor failures — on site with the correct testing equipment and parts.

If your bar fridge, undercounter fridge, or display refrigeration unit has stopped working, is not holding temperature, or is cycling incorrectly, get in touch with our team.

Call Brendan on 0419 149 758 or email info@bmrs.com.au.

Frequently Asked Questions — Bar Fridge Control Board and Relay Repairs

A relay is an electromechanical switch on the temperature control board. It receives a signal from the thermostat and uses that signal to switch power to the compressor on and off. When the relay fails, the control board cannot operate the compressor regardless of whether the compressor itself is in good condition.

Testing the control board and its components separately from the compressor and refrigerant system is the way to make this distinction. A relay failure produces a specific set of test results that confirm the board is not sending power to the compressor. A compressor fault produces different results. Getting this diagnosis right at the start determines the correct repair pathway and avoids unnecessary parts replacements.

Yes, provided the replacement relay matches the original component’s electrical specifications — switching capacity, voltage rating, and physical footprint. A correctly specified compatible relay performs the same function as the original and fully restores the board to its intended operating condition. This is standard practice in commercial electronics repair.

In most cases this type of repair can be completed in a single visit. The diagnosis, component replacement, board reset, and operational test were all completed in one visit on this job. The exact time depends on the unit and what testing is needed to confirm the fault.

Not necessarily. A unit that appears completely non-operational can have a fault as simple as a failed relay on the control board. Before assuming a unit needs to be replaced, a component-level diagnosis should always be carried out. In many cases the repair is straightforward and can be completed on the same visit.

Yes. BM Refrigeration repairs Williams bar fridges and all types of commercial refrigeration equipment across Sydney CBD and the greater Sydney area. Get in touch to arrange a diagnostic visit.