Our Rating
Summary:
4.9
If you need an energy efficient water heater that can be used outdoors, in the past the options available to you would be rather limited. Add in the low nitrous oxide requirements that some jurisdictions have and the task would be virtually impossible. Thanks to the Rheem 64XLN outdoor tankless water heater, however, that search for a perfect unit can finally come to an end.
Why choose this water heater? Not only can it be placed outdoor, but it uses natural gas and meets low nox laws so that virtually everyone can use it. At 6.4 gallons per minute, its maximum capacity, this water heater will provide a 35F temperature change. It also has an industry best 0.26 GPM minimum flow rate to begin producing hot water.
Could this be the perfect tankless option for you? Here are a few of things we noticed when taking a look at this water heater.
#1. A 5.3 GPM flow rate maximizes what this water heater can do. If users can reduce the amount of hot water they need to use, then the temperature of that water will be hotter and more consistent. We found a flow rate just above 5 GPM was the best result. Keep in mind that some older showers can use 5 GPM on their own.
#2. The burner technology in this water heater is fantastic. The Rheem 64XLN takes burner technology to a new level. The results are more consistent, especially with low level water needs, so that hot water can run continuously at 2 GPM levels. You really can keep using a faucet continuously and not run out of hot water with this unit.
#3. There is less of the on/off hot water problems with this unit. Many minimum flow rates are 0.4 or even higher to get the hot water to be used. Some low flow faucets are designed to conserve so much water that they can be fully on and not use enough water to trigger the tankless unit. Rheem hasn’t fully solved this problem with the 64XLN, but it is a lot better with the 0.26 minimum GPM rate.
#4. It needs a 0.75 inch gas line. You don’t have to worry about venting with this particular unit since it has to be mounted outside. It’s relatively quiet, so the neighbors aren’t going to be bothered by extra sounds. What most users find, however, is that their gas lines aren’t the right size for this unit.
#5. Don’t try to start this unit until everything is hooked up to it. This water heater will not start unless you have water, gas, and electricity hooked up to it. If you do try to start it, then you may need to reset the thermostat to get it to work after you do have everything hooked up.
#6. Invest in a valve servicing kit. This outdoor water heater will need regular servicing. Some homeowners may need to service this unit once per quarter or even more frequently. The kit will make this chore a lot easier.
Do not try to install this water heater inside, even if you have a lot of ventilation. It is an outdoor unit only. We found the Rheem 64XLN outdoor water heater to be an excellent unit that performed very well. It may work best for smaller homes and applications, but it will get the job done if you stay below the GPM maximums. That’s why we’re recommending this water heater today.