In need of CE

[Robert Jones]

I am not familiar with this setup on this new water heater. What is the pipe connected to both water lines?

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[AHI in AR]

I've not seen that setup before but is it some sort of thermal expansion device?

[Robert Jones]

I am not sure Kevin. It did have a thermal expansion tank installed.

[inspector57]

I have not seen that particular setup but it reminds me of a tempering valve on one of the high capacity units that is designed to replace a larger or dual tank with one smaller tank. The water is heated and held at a much higher temperature and is mixed with cold water at the tank outlet to provide a safer temperature.

[hausdok]

Hi Rob,

It is a tempering valve. It mixes cold water with the hot to deliver water to the house at the temperature chosen by the user with that little temp control. On the water heater it controls temp of all water going to the house. Around here, there are one or two plumbers installing them on the master bedroom pipes only.

The bigger builders here use them as a way to make folks think they are getting a great water heater. They are able to crank even a 40-gallon water heater up to full temperature so that it cycles more quickly and deliver a lot more hot water to the house at a safe temperature.

The problem with installing them under the sink in the master bath like so many do around here, is that when you crank the temp way up to deliver what seems like unlimited hot water to the master bath, the water delivered to the powder room is at 145 - 150 degrees.

Imagine that you have one of those and your best friend comes over with his wife and four year old son for dinner. Before dinner, your friend tells his son to go and wash his hands for dinner like Dad taught him. The kid dutifully complies and a minute later they hear a gawd awful shriek coming from the powder room. When they go to investigate they discover the 4-year old with severe third degree burns on both hands because he'd been scalded by the hot water. There goes your friendship.

When you see those, make sure you explain to the customer that he or she must test the temperature of the water at the powder room when taking possession of the house and ensure it is never more than 120 degrees. Once they understand the device's purpose and how dangerous they can be when the temps are run at higher-than-normal temps to make the tank recover more quickly, they often ask me to show them how to adjust the temp to 120 and set the tempering valve to neutral.

ONE TEAM - ONE FIGHT!!!

Mike

[Tom Raymond]

I never thought of flooring the tank to increase recovery rate. Maybe... never mind, my 11 year old would never get out of the shower.

[kurt]

I never thought of flooring the tank to increase recovery rate. Maybe... never mind, my 11 year old would never get out of the shower.

One of the problems of *on demand* water heaters. Showers stretch to days.