One of my customers had a problem with his Rheem Proterra heat pump water heater, it was tripping the breaker on a daily basis.
The Way It Works
The Proterra is a hybrid system, it utilizes a combination of a heat pump and electric resistive heating to ensure the domestic hot water stays at set point. It can be set up in a few different ways to achieve this. But we’re not here to discuss its operation, we’re here to find out why it was tripping.
The Problem And The Solution
After a quick visual everything looked okay, expect for signs of over heating on the upper resistive element.
The tank is rated for 240v but the incoming voltage was 255.4 volts, after an hour or two, the voltage had increased even more so. I informed the customer and he then contacted the utility, they showed up within an hour and corrected the situation. After the voltage reduction, the breaker did not trip again.
Check out this Instagram post and conversation on this topic.
Utility Over Voltage Is A Serious Problem
The utility company’s swift response demonstrates they take these voltage issues seriously, as excessive voltage can cause widespread issues beyond just one appliance. This case serves as an excellent reminder why taking multiple voltage readings over time, rather than a single snapshot measurement, can reveal developing problems that might otherwise go unnoticed.
Learn more in the following a short podcast where this call is described in detail.
Side Note: Don’t Jump To Conclusions – Measure First (And Often)!
Voltage in the 253v range can be a slow death for sensitive electronics. My suggestion: Don’t go staright to, “that unit is a piece of shit”. Be thorough, check your incoming voltage.
This where voltage monitoring can come in handy, it can be set up to shut down equipment if voltage becomes too high or too low (brown out) and can be paired with a surge device for added protection.
I recorded a podcast with this particular customer as to why he chose to go the electrification route for his heating, cooling and water heater.
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