Honeywell AM-1 Thermostatic Mixing Valves. ( water heater tempering )

Users who are viewing this thread

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,461
Points
113
Location
Bothell, Washington
Website
terrylove.com
Honeywell AM-1 Series Thermostatic Mixing Valves. ( water heater tempering )
Many plumbing codes require a tempering valve to prevent scalding if you have a tub that people bath in. A tempering valve takes the cold water and mixes it with hot water and dials it down to a suitable temperature.
Some adjust between 70 F and 120 F
And you can also get one that does 70 F to 145 F

Raising the water in the tank to 140 F helps to prevent the growth of Legionella bacteria.

honeywell_am_1_a.jpg


1

honeywell_am_1_b.jpg


2

honeywell_am_1_c.jpg


3

honeywell_am_1_d.jpg



• Allows homeowners to store water at 140 F and
higher to prevent legionella growth, but receive
safe, comfortable 120 F water at sinks, shower
or tub
• Designed to increase the amount of usable hot
water by up to 50 percent
 
Last edited:

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,461
Points
113
Location
Bothell, Washington
Website
terrylove.com
Installing the AM-1

honeywell_am_1_fig_1.jpg




honeywell_am_1_fig_2.jpg


2



honeywell_am_1_fig_3.jpg

3

With a recirc pump and a tempering valve, you will also need an aquastat to prevent the temperatures from climbing. Without an aquastat, the entire hot line, including the return line will climb in temperature to as high as what the water heater has been set to. With the aquastat, once the return line come back warm, it turns off the pump, preventing temperature overrun.

grundfos_aquastat.jpg


Grundfos makes this clip-on aquastat that fits onto the 1/2" return line.
 
Last edited:
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks