I recently replaced my leaking water heater with a tankless model, specifically the Rheem rtex 13, but it hasn't really met my expectations. It struggles to heat enough water for more than one shower at a time! I'm planning to return it to Home Depot and opt for the 27kW version instead. Given that I installed the current unit using 6 gauge wire (220V, 60 amps), I'm curious if it's okay to run only two sets of 8 AWG wires for the new unit while keeping the existing 6 AWG. Will this configuration potentially cause any issues?
4 Answers
You're diving into electric tankless, huh? Good luck with that! Honestly, though, I’d suggest cutting your losses and maybe just switching back to a traditional tank. Also, heads up—if you're considering returning it to Lowe's, check their return policy because they can be pretty strict about water heater returns.
Just a heads-up, where do you live? Make sure you checked the temperature rise chart for the new heater. The 27kW will only raise water about 31 degrees at 6 gallons per minute. If you're in a place with cold water, you might end up disappointed.
Make sure to check whether the new unit can handle the 6 gauge wire. Most likely, it should be okay, since the breakers typically support up to 2 gauge. Just confirm that the breaker you have can handle 6 gauge as well.
That’s a lot of power usage! Have you thought about going with a heat pump water heater instead? You could significantly cut down on your hot water electricity use, maybe even by 60% or more.