How to remove water heater
Always protect flooring
Advantages and disadvantages of mixing valve
How to save Hot water using a mixing valve

Search 
sitemap button
Search using google with ads

 Tweet button  
replace anode rod
Inspect anode each 2-5 years
Anode rod prevents tank from rusting
Buy:
Anode rods at Amazon

Resources:
Replace anode rod
How to maintain water heater
Water pressure gauge

Pressure gauge/ attach to water heater drain valve
Pressure over 80 psi can damage water heater and household plumbing
Buy:
Water pressure gauge
Temperature-pressure gauge

Resources:
Identify water heater valves
Troubleshoot water pressure
89T thermostat kit
Electric water heater thermostats
Thermostats stick, melt and come out of calibration... replace thermostat
Symptoms: Cold water, uneven temperatures, reset tripping, TP releasing water

Resources:
How to replace electric water heater thermostat
Add another thermostat to water heater
How to wire thermostats
Marathon water heater thermostats
Two water heaters
Troubleshoot electric water heater
Icon gas valve   
Gas water heater thermostats
If tank is overheating or not heating correctly, replace thermostat
Symptoms: Cold water, uneven temperatures, TP releasing water

Resources:
How to replace gas water heater thermostat
Add another thermostat to water heater
Troubleshoot gas water heater

Honeywell mixing device

Mixing valve
Mixing device/ valve only
Simple mixing device can be added at water heater or under sink
This can solve problem of uneven hot water arriving at tap
Children can be protected from scalding at their bath or faucet
Solder all pipes, then attach pipes to water heater last, so high temperature cannot damage heater.
Honeywell mixing device    

Buy:
Water heater mixing valves
Honeywell mixing valves
Watts mixing valve
Taco mixing valve
Mixing valve 1/2 NPT
Mixing valve 3/4" national pipe thread
Resource:
How to solder pipes
Advantage
Every water heater manual suggests mixing valve Why?
More hot water and safety from scald

First hour delivery means the amount of usable hot water from a single continuous draw.
You can increase first hour delivery of water heater by setting the thermostat higher.

The risk of high temperature water coming from tank can be solved by using a mixing valve.
For example the tank is set to 145°F, but mixing valve is set to 120°F...
... then the mixing valve adds cold water to the line...
... and maximum water temperature at any tap is safe 120°F

This means more hot water is stored inside tank so you get higher first hour ...
... without risk of scald.
Advantage
Save energy  How? Less water cold enters tank so tank runs less

Each faucet; bath, kitchen, shower and tub faucet is a mixing valve... where you manually adjust water temperature by adding cold.

Each time hot tap is turned on, new cold water immediately enters bottom of water heater as hot water leaves top of tank going to shower..

Sometimes it takes a minute for hot water to arrive.

Because the tank is storing very hot water, and the mixing valve is adding cold water, then less cold water is entering bottom of tank.

So there is less cold water entering tank, which means less energy is needed to re-heat tank after every draw.

You can save more by only turning on the cold side if no hot is needed.
Remember, a single handle faucet lifted in the middle will draw hot from tank, and new cold enters bottom of heater.
Advantage
Save water  How?

A mixing valve is exactly what you do during shower ... you add cold water to hot.
When you use mixing valve located at water heater instead of mixing valve located at shower, then you save the amount of hot water that travels down the pipe going to shower.
How much hot water is saved?
Every 10 feet of 1/2 pipe holds .12 gallons of water.
If bathroom is 20 feet away. 3 showers per day .72 gallons per day x 365 days = 262 gallons of cold water that does not enter tank.
That means 262 gallons of cold water is not heated to thermostat set point.
The math can be more complex than this 2-D example. But a mixing valve keeps more cold water out of tank, and water heater stays hotter
Adding mixing valve is required for solar water heater. Because sipping Hot is important strategy for preserving the solar heat stored inside water heater.

Water heater is energy battery. Don't drain the battery.
Advantage
Easy water temperature adjustment  How?

A mixing valve is easy way to adjust temperature right at top of heater without bending over

Advantage
Better than buying a larger heater  What are you talking about?

After 2015/04, electric residential water heaters bigger than 55 gallons will have to be heat pump. Gas heaters will be condensing.

Adding a mixing valve will help fill that garden tub without the hassle and expense of buying a heat pump or condensing heater.
Resources
Which is best heat pump
Ways to increase amount of hot water
Two water heaters
Review Polaris condensing heater
Disadvantage
Disadvantages of Mixing Valve:

1) Running water heater at increased water temperatures may cause increased amount of calcification to precipitate out of the water requiring more frequent cleaning and shorter element life.
Depends a lot on water quality, hardness, temperature settings, etc.

2) Increased water temperature in tank will mean more stand-by loss.  However, it may not be as bad as a larger equivalent size tank which has greater surface area to lose heat through.

3) Increased installation space.  The Honeywell kit installs right on top of the tank hot and cold connections increasing installation height by several inches.

4) Cost and installation ... not everybody wants a DIY project
Mixing valve
Mixing valve adds cold water to hot line so water temperature remains constant.

1) This lets you heat tank full of very hot water during good solar days if you use solar heating.
2) This lets you heat full tank of hot water during low peak pricing periods overnight.
3) This lets you send very hot water to washing machine on separate water line, and send tempered hot water to other water line going to faucets and kids bathroom.

Mixing device kit
Kit has more features/ scroll down for mixing valve without kit
I run my water heater upper and lower thermostats at max (150F they are NOT heavy duty 170F thermostats). See thermostats
I have my mixing valve set so I get 112F water (my preference) on the hot side at the kitchen tap.    

Without a mixing valve I would have to set my thermos at 110F instead of 150F.  Because I have a higher setting on my thermostats I can store the excess energy from a sunny day (solar heat), or store excess heat from low electric price.
The water heater stores energy. .. basically the extra BTU it takes to heat the water from 112F -> 150F).  
I think my calculations are that my 105 gallon water heater can store the equivalent of 150 (or more) gallon water heater depending on the incoming cold temp (time of year related). 

With the mixing valve my water heater stores about 20-25KWh of energy.

Do you have a mixing valve in your setup?

Buy:
AMX302T Mixing valve kit

Resource:
Mixing valve .pdf
di-electric nipples Use di-electric nipples for connections at top of water heater
Di-electric nipples help prevent corrosion at water pipe connections
Di-electric nipples are good replacement for factory-installed heat trap nipple that might cause clogs and noise
Buy:
Di-electric nipples
Resources:
Low hot water pressure
New water heater making noise
How to remove short water heater nipple
Mixing valve kit
Larger image
Mixing valve kit installed on top of tank
This installation shows standard gas or electric water heater
Mixing valve kit installed on top of tank
5 total ports for connections

Laundry/ washing machine / receives very hot water
Sinks and bathtubs receive tempered water at lower temperature

Mixing valve has a thermostatic setting knob
Mixing valve automatically releases cold water into the water going to sink
The cold water reduces temperature of water that travels to sink
Buy:
AMX302T Mixing valve kit
Water heater mixing valves

Resource:
Mixing valve .pdf
mixing valve
temperature gauge
Temperature gauge<
Permanent install on hot pipe leaving water heater.
Use brass adapter... stainless can deteriorate if water is softened
Buy:
Winters Temperature gauge
Temperature-pressure gauge for boiler
1/2" to 1/4" brass adapter
Pocket thermometer
Mixing valve Mixing valve installed with pipes
This installation shows example gas water heater
Mixing valve installed to side of tank

Laundry/ washing machine / receives very hot water
Sinks and bathtubs receive tempered water at lower temperature

Mixing valve has a thermostatic setting knob
Mixing valve automatically releases cold water into the water going to sink
The cold water reduces temperature of water that travels to sink
Larger image
Super high volume system
Storage tank and heat pump/ DIY
Purpose to increase storage capacity to meet high volume demand.
Typically, a gas water heater is used for high volume systems, and not heat pump. Storage tanks are available in 150-200 gallon etc and rated for high temperature applications.

Tankless will stall and quit heating when demand exceeds parameters of unit. Even 3 tankless heaters can stall.

Heat pump supplies hot water that circulates into the storage tank.
Storage tank thermostat controls circulating pump, so when water drops below set point inside storage tank, the heat pump replenishes the hot water.
Storage tank can contain super-dangerous 140+°F water. The mixing valve located on top of storage tank, adds cold water to the line, so end user receives 115°F water.
This strategy increases the amount of hot water available to meet high volume demand. Typical bath-shower is 104-110°F.
Buy:
AO Smith Storage tank
Rheem thermal storage tank
Resources:
Advantages disadvantages mixing valve
Plumbing for 2 water heaters and Storage tank pdf
Advantages of Mixing Valve:

1) Increased hot water storage capacity.  Instead of replacing a good working water heater with a bigger one that costs more and takes up more space, add a mixing valve and turn up the thermostats.  Works with Gas or Electric water heaters.

2) After 2015/04, electric residential water heaters bigger than 55 gallons will no longer be inexpensive and easy to install.  A mixing valve will help you fill that garden tub without the hassle and expense of an electric heat pump water heater.

3) Perfect for thermal or photovoltaic solar hot water heating because of increase in storage capacity.  More capacity is always better.  Instead of just throwing away the excess energy, store it in the tank for a cloudy day.

4) Bacteria that causes legionnaires disease can grow in a water heater at a temperature between 68 and 122F.  Inhaling the bacteria laden hot water steam in a shower is the worst thing you can do with it.  Bathing and hand washing dishes is less of a hazard.  Very hot water will kill this bacteria.   The length of time it takes depends on the temperature of the water in the water heater.  

* 70 to 80 °C (158 to 176 °F): Disinfection range
* At 66 °C (151 °F): Legionellae die within 2 minutes
* At 60 °C (140 °F): Legionellae die within 32 minutes
* At 55 °C (131 °F): Legionellae die within 5 to 6 hours
* Above 50 °C (122 °F): They can survive but do not multiply
* 35 to 46 °C (95 to 115 °F): Ideal growth range
* 20 to 50 °C (68 to 122 °F): Legionellae growth range
* Below 20 °C (68 °F): Legionellae can survive but are dormant

5) Very hot water can also quickly scald skin.  Children and the elderly can have reduced reaction times, delicate skin and can get very badly scalded by hot tap water.   65% of all hospitalized burn-related injuries in children under 4 years old are directly related to dangerously hot tap water in residences.  
A mixing valve can make tap temperatures safe even when running a water heater at maximum temperatures.

6) Convert electric water heater from 240 volts to 120 volts so the elements run at 1/4 wattage and last forever.  Use mixing valve to increase storage capacity so you do not notice the massive decrease in hot water recovery rate.

7) Some mixing valves like the Honeywell kit have bonus connections for hot water recirculation kits and untempered hot water for cloths washer and dishwasher.

8) The dial that moderates the temperature of the tempered hot water on a mixing valve is much easier to adjust than the thermostats on an electric water heater.   This makes fine tuning temperature at the tap simple and easy.  Possible to temporarily increase water temperature for a short task and then put it back back down when done.

9) The dial the moderates the temperature of the tempered hot water on a mixing valve INSTANTLY changes the temperature coming out of the water heater.   Changing thermostat settings requires time for the water heater to heat the water up to the new setting or lose enough heat with water usage or stand-by loss to reduce temperature.

10) Mixing valves *may* be better regulation of the temperature of the hot water at the tap compared to thermostats that kick water heating on and off.  Depends on quality of mixing valve and thermostats.





Buy
Tools
DEWALT
Black and Decker
Stanley
SKIL
Makita
Porter-Cable
Bosch

Irwin Hand tools
Klein hand tools
Fluke electrical testing
Dremel hobby tools

Campbell Hausfeld air powered
Tekton automotive

Powerbuilt automotive
Saws and saw blades

Buy from my affiliate links every time/ thanks:
Amazon
''As an Amazon Associate I earn from qualifying purchases''
Enter Amazon from any link on my site, fill cart with any item ... purchases pay small commission

E-mail: geno03245w@gmail.com
My response might end up in spam folder, check email folders
Waterheatertimer on Twitter
Message thru facebook