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Whole House Tankless Electric Water Heaters

by Stiebel Eltron

If you need a space-saving, reliable, whole-house tankless water heater, you've come to the right place.® is pleased to offer the Stiebel Eltron line of electric tankless water heaters - a proven line of dependable, technologically advanced heaters that are built to last. Tankless water heating is here to stay, and continues to gain popularity as more people learn of the great benefits of on demand water heating. We are your source for tankless water heaters and thousands of other plumbing-related products.

Tempra® Whole House Electric Tankless Water Heater

Tempra whole house electric tankless water heater

These whole house electric tankless water heaters feature:
  • Unlimited Supply of Hot Water - Keeps heating water instantly, as you require it. The Tempra® system completely replaces a conventional tank heater with no disruption to your comfort and hot water needs.
  • Saves Energy and Reduces Your Electric Bill - Electric tank type water heaters are subject to stand-by losses which amount to 15 - 20% of the kWH used. Changing to a tankless system results in savings of 15 - 20%.
  • Sleek Design Saves Space - The Tempra® takes up considerably less space than conventional tank type water tanks and saves valuable living space.
  • Control Temperature Simply by Setting a Dial - Set the knob on the front cover and enjoy water temperatures between 86°F (30°C) and 125°F (52°C). Change the desired temperature at anytime. Advanced microprocessor technology ensures that the water temperature never deviates from the set point.
  • Proven Reliability - Three years manufacturer's parts warranty
  • Seismic Proof Construction - The Tempra® is a tankless water heater system, and is thereby not subject to seismic code. There is no need for preventative construction, as required when using a tank type water heater.
  • Superior, Reliable Performance - The Tempra® has several temperature and flow sensors which feed their readings into the unit's proprietary microprocessor control. Heating elements are engaged in stages, achieving the temperature you desire. The Tempra® continually monitors the water temperature it produces.
  • Advanced Flow Control™ - The Tempra® Plus models include the Advanced Flow Control™ to help ensure a constant temperature output no matter how large of a demand. The Advanced Flow Control™ works by automatically adjusting the flow of water to make sure the required hot water output is always met while eliminating unpleasant temperature fluctuations.
  • Ideal for homes, condos, apartments, and various commercial uses.
  • Specifications - See below.

208/240V - Large Capacity Tankless Electric Water Heaters
w/ Digital Temperature Control

Model# Description Price & Quantity
Tempra® 12 Plus 9.0 kW, 208V or 12kW, 240V large capacity unit $529.49
Tempra® 15 Plus 10.8 kW, 208V or 14.4kW, 240V large capacity unit $642.85

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208/240V - Whole House Tankless Electric Water Heaters
w/ Digital Temperature Control

Model# Description Price & Quantity
Tempra® 20 Plus 14.4 kW, 208V or 19.2kW, 240V whole house unit $689.56
Tempra® 24 Plus 18.0 kW, 208V or 24kW, 240V whole house unit $739.14
Tempra® 29 Plus 21.6 kW, 208V or 28.8kW, 240V whole house unit $769.31
Tempra® 36 Plus 27.0 kW, 208V or 36kW, 240V whole house unit $809.88

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Ball Valves - click here for more ball valves

ball valve

These ball valves feature:
  • Keepalloy® lead-free alloy
  • Full port design keeps flow unrestricted
  • Meet or exceed Federal Safe Drinking Water Act standards
Description Price & Quantity
Valve - 3/4" FIPS
Order 10, 50, 100 or more for extra savings!
Valve - 3/4" Sweat
Order 10, 50, 100 or more for extra savings!
Stainless Steel Nipple - 3/4" IPS x 1-1/2" Long $3.80

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Water Connectors - click here for more flexible water supply lines

Ultraflow gas connectors

  • Stainless steel water ways inside
  • Great for tankless water heaters and more
  • UPC and ASME A112.18.6 compliant
  • IAPMO listed
  • Purchase 10 or more (of the same size) for additional savings

Description Price & Quantity
Flexible Corrugated Stainless Steel Water Connector - 3/4" FIP x 3/4" FIP - 18" Long $6.78
Flexible Corrugated Stainless Steel Water Connector - 3/4" FIP x 3/4" FIP - 24" Long $7.53
Flexible Corrugated Copper / Stainless Steel Water Connector - 3/4" FIP x 3/4" Nom Sweat - 18" Long $6.93
Flexible Corrugated Copper / Stainless Steel Water Connector - 3/4" FIP x 3/4" Nom Sweat - 24" Long $7.55

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Water Heater Scale Inhibitor System

image of complete scale inhibitor system
This scale inhibitor system features:
  • Highly effective in treating scale, corrosion and iron build-up for up to 6 months
  • Food-grade hexametaphosphate crystals dissolve slowly in water to prevent lime, scale and rust build-up
  • Forms a protective coating on all metal surfaces, safeguarding against acidity/alkalinity, hardness, chloride and other factors which effect the corrosion of water equipment and pipes
  • Maintains efficiently and extends life of system
  • Up to 5gpm
  • Recommended for use with water heaters, ice machines, vending machines, food service equipment, air conditioning and many other types of water processing applications
  • If using on a water heater, it needs to be installed on cold water line entering the water heater
  • Dimensions: 2 7/8" x 9 5/8"
  • Recommended time to change/replace this inhibitor cartridge is 4-6 months
  • It's a good idea to purchase a replacement cartridge to have on hand when needed!
  • For more information, go to our Scale Inhibitor Page

Description Price & Quantity
Scale Inhibitor System:
includes housing, cartridge and mounting bracket
Replacement Inhibitor Cartridge
Save on shipping by ordering replacement cartridge now!
Mounting Bracket:
included with Scale Inhibitor System

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FloodStop Systems for Water Heaters

water heater flood stop

Automatically shuts off the water supply to the water heater and sounds an alarm, leaving all other household fixtures and appliances operational. Powered by AC Adaptor/Transformer or Batteries. Output contacts available, which allow the Controller to connect with Alarm, Home Automation or Auto-Dialer systems if desired. Easily installed in fifteen minutes. 1-Year Manufacturer's Warranty.

Description Price & Quantity
FS 3/4-NPT-V4 - 3/4" Pipe threaded - full-port motorized ball valve
- Works with any 3/4" MIPT supply line - rated 0-180 psi
New Style Controller - uses 4 each AA batteries
FS 3/4-C-V4- 3/4" Compression - full-port motorized ball valve
- Works with any 3/4" copper applications - rated 0-180 psi
New Style Controller - uses 4 each AA batteries (not included) for back-up
Make sure to follow all of the manufacturer's instructions and directions by performing the proper maintenance and inspections to ensure that you are fully protected from flooding -this is ever-so-important with (man-made) safety devices as they will eventually fail.

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Related Items & Information

Technical Data

Tempra tankless water heater inside

Tempra Model 12 15 20 24 29 36
Phase 1 1 1 1 1 1
Voltage (V) 208 240 208 240 208 240 208 240 208 240 208 240
Wattage (kW) 9 12 10.8 14.4 14.4 19.2 18 24 21.6 28.8 27 36
Amperage (A) 44 50 52 60 70 80 88 100 105 120 132 150
Min. required circuit breaker size (A) 50 60 2 x 40 2 x 40 2 x 40 2 x 50 2 x 50 2 x 60 3 x 40 3 x 50 3 x 50 3 x 60
Recommended wire size (AWG COPPER) 8 8 2 x 8 2 x 8 2 x 8 2 x 8 2 x 8 2 x 8 3 x 8 3 x 8 3 x 8 3 x 8
Max. temp. increase above ambient water temp. @ 1.50 gpm 41 54 49 65 66 88 82 92 92 92 92 92
@ 2.25 gpm 27 36 37 43 44 58 54 73 66 87 82 92
@ 3.00 gpm 20 27 25 33 33 44 41 54 49 66 61 82
@ 4.50 gpm - - - - 22 29 27 37 33 44 41 55
Min. water flow to activate unit (gpm/Lpm) 0.29/1.1 0.58/2.2 0.58/2.2 0.58/2.2 0.87/3.3 0.87/3.3
Weight (lbs/kg) 15/6.8 18/8.1 18/8.1 18/8.1 24.25/11 24.25/11
Nominal water volume (gal/L) 0.13/0.5 0.26/1.0 0.26/1.0 0.26/1.0 0.39/1.5 0.39/1.5
Height x Width x Depth (inch) 14-1/2" x 14-9/16" x 4-5/8" 14-1/2" x 21-3/4" x 4-5/8"
Working pressure (PSI/bar) 150/10
Tested to pressure (PSI/bar) 300/20
Water connections 3/4" NPT

Tempra temperature rise chart

Note: If you're replacing multiple water heaters (old tank style), you may want to order a water heater drain pump to reduce labor by quickly/easily removing the water.

Frequently Asked Questions

Q. "Each unit shows two different kilowatt (kW) and voltage (V) settings, what does that mean?"
A. Each unit can be wired in two different ways, 208V or 240V which results in two different kW ratings.

Q. "Will an instantaneous water heater save me money on my utility bills?"
A. In many applications you can see a savings. There are some variables that could reduce the amount you save. One example is you will not run out of hot water, so longer showers could cut into your savings. Also, the cost of electricity, propane and natural gas in your area will affect the amount of money saved. The higher the cost for the energy type used to heat your water, the quicker you can recover the higher initial cost of installing a tankless versus tank style water heater.


  • You will never run out of hot water. "You want an hour long shower? No problem!"
  • Electric units can be installed at the point of use.
  • You're not paying energy costs to heat water 24 hours a day.
  • They're easy to install.
  • Our electric units don't require a T&P valve (no tank!) - if code allows
  • Installing a tankless water heater can indeed be a bonus to the environment (why should we choose wastefulness when we're talking about finite natural resources?)


  • They all need a minimum flow rate & pressure to turn on.
  • The faster water flows through them, the lower the temperature rise. So, if you expect to take a shower while the clothes washer is running, you will need to select a unit sized to your maximum hot water flow requirements. (Gas units generally handle this a little better than electric models)
  • Electric units need heavy gauge wire. Example: the 9.5kw must have 8ga wire and a 50amp breaker.
  • Gas units need a much larger, special flue pipe and larger gas supply than a conventional water heater.
  • At times they can produce very hot water. It's easier to get scalded.
  • Gas units are more complicated than a conventional water heater.
  • With some brands, parts are hard to find (not a negative if you originally purchase from us, as we like to carry parts for the units that we sell).

Tankless water heaters have their place. They're not "the answer" to every hot water need, but if they're used correctly they can be the solution to many of them.

Q. "I'm hearing a lot about lead-free these days. What does that have to do with plumbing products and how does the new lead-free legislation affect me?"
A. Basically, the laws implemented Jan. 1st, 2014 require plumbing products that come in contact with drinking water to be "essentially lead free" (less than 0.25% weighted average). For further information about how the law determines what is "lead free", rules regarding which plumbing products must be "lead free", and who these laws will affect, please click here.

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