Mobile View HEATING SYSTEMS
PLUMBING TOPICS
HOT WATER HEATERS
AGE of WATER HEATERS
ALTERNATIVE HOT WATER SOURCES
Electric Shower Heaters
High Efficiency Water Heaters
Indirect-fired Water Heaters
Instantaneous Water Heaters
Multiple water heaters in parallel
Multiple water heaters in series
Range Boiler Water Heaters
Side Arm Coil Water Heaters
Solar Water Heaters
Tankless Coil for Hot Water
Tankless Water Heaters
Guide to Tankless Water Heaters
Operation & Characteristics
Problems & Defects
Hot Water Delivery Speedup
Installation Requirements & Costs
Should I Convert to a Tankless Heater?
Calculate Water Heater Requirements
Capacities of Tankless Water Heaters
Life Expectancy & Applications
ANODES & DIP TUBES on WATER HEATERS
ANTI SCALD VALVES
CARBON MONOXIDE/DIOXIDE
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CLOGGED PIPING & Hot Water Flow
ELECTRIC WATER HEATERS
GAS FIRED WATER HEATERS
DRAFT HOODS - gas fired
Gas BTUH & Cubic Feet
Gas Conversion LP Natural Gas
GAS PIPING, VALVES, CONTROLS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
HOT WATER IMPROVEMENTS
HOT WATER DELIVERY SPEED UP
HOT WATER QUANTITY IMPROVEMENT
Alternative Hot Water Sources & Methods
Anti-Scald Valves & Hot Water Quantity
CLOGGED PIPING & Hot Water Flow
Extra Tanks to Increase Hot Water
Insulate Hot Water Piping
Insulate Hot Water Tank?
Larger Diameter Water Supply Piping
Temperature of Hot Water is Too Low
INDIRECT FIRED WATER HEATERS
NO HEAT - NO HOT WATER: HEATER DIAGNOSIS
NOISES COMING FROM WATER HEATER
ODORS IN WATER
OIL FIRED WATER HEATERS
DRAFT REGULATORS - barometric dampers
OIL BURNERS
OIL BURNER NOISE SMOKE ODORS
OIL PIPING
OIL TANKS
MIXING VALVES
PLASTIC HEATER VENT
RANGE BOILERS
RELIEF VALVES - TP Valves on Boilers
Relief Valves - Water Heaters
SAFETY DURING HEATING INSPECTION
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
TANKLESS COILS
Clogged Piping / Tankless Coil & Hot Water Flow
Mixing Valves
Tankless Coil Leaks
Tankless Coil Hot Water Increase
TANKLESS WATER HEATERS
Temperature Pressure Relief Valves - Water Heaters
Water Heater Noises
WATER HEATER PROPERTIES
Electric, Gas, Oil Water Heater Efficiency
Water Heater Life Expectancy Comparisons
Water Heater Operating Cost Comparisons
Water Heater Purchase & Maintenance Costs
Water Heater Water Quantity Comparisons
Water Heater Recovery Speed Comparisons
Water Heater Safety Comparisons
Water Heater Scale - De-Liming Procedures
WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER QUANTITY IMPROVEMENT
WATER QUANTITY USAGE GUIDE
WATER SOFTENERS
More Information
InspectAPedia ® Home & Site Map InspectAPedia Blog - News Updates
Air Conditioning & Heat Pumps
Bookstore
Electrical
Environment
Exteriors
Heating
Home Inspection
Insulate Ventilate
Interiors
Mold Inspect/Test
Plumbing Water Septic
Roofing
Structure
Accuracy & Privacy Policies
Contact Us
|
Here we discuss the operating characteristics of electric shower heaters, also called instant water heaters or "on demand" water heaters for point of use at shower heads. Readers should also see Tankless Water Heaters. Photos of electric shower heaters are courtesy of Arlene Puentes.
© Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use the links at page left to navigate this document or to go to Other Website Topics. Green links at left show where you are in our document & website.
A Guide to Electric Shower Water Heaters
An instant hot water point of use system like the shower heaters we show here are a very different approach to making hot water for bathing than the tankless water heaters discussed above. These electric shower heads work where the incoming water temperature is pretty high to start and where the water flow rate is modest. Electric shower water heaters are typically used where a central hot water heater is not installed. The heater is installed directly on the shower water piping at the location where a conventional shower head would otherwise be found.
|
These electric point of use water heaters are typically installed in buildings where no water heater or hot water source has been provided. When a sensor in the shower head detects water flowing, the electical heating element turns on. An electrical element heats water as it enters and flows through the unit, drawing typically about 23 amps (when wired at 110V 2400 watts) or 13.5 amps (when wired at 220V 2900 watts). The temperature of the hot water received depends on the flow rate through the heater. Slower flow rate yields hotter water. Flow rates are limited, however, with a maximum water pressure of 2 gpm and a minimum water pressure (to activate the unit) of 0.83 gpm. The average water temperature increase across this range is 10-25 degF. |
|
That means that if the incoming water temperature is 42 deg.F. (northern U.S. and Canada) your hot shower might reach 67 deg.F. at the slowest flow rate of less than 1 gpm. Not a hot shower. These point of use electric showers are intended to work in areas where the incoming water is already not very cold, such as the more tropical climate of Puerto Rico, where Duro-Matic is based. The Mini Marey tankless shower heater (photo at left) is advertised for use in boats, cabins,campers, recreational vehicles (RV showers), mobile homes, apartments where no central water heater is provided. Puentes, who inspected a large number of electric shower installations in Puerto Rico in 2009 reported that perhaps because these devices were installed in homes of people of limited means, many of them were simply turned off entirely in an effort to reduce the occupant's electrical bill. We found the exposed electrical wiring at some of these point of use electric shower heaters disconcerting and a possible electrocution hazard, particularly where the wiring was not GFCI protected. Be sure that your electric shower heater is wired according to local and national electrical codes. |
Share this Article
...
Technical Reviewers & References
 Search InspectAPedia |
- Daniel Friedman - principal author/editor of the InspectAPedia® Website
- InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also include a list of recommended books for the specific article topic as well as other references, and information sources.
- Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
- Additional technical contributors & reference sources for this article are listed below.
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
ALTERNATIVE HOT WATER SOURCES
Electric Shower Heaters
High Efficiency Water Heaters
Indirect-fired Water Heaters
Instantaneous Water Heaters
Multiple water heaters in parallel
Multiple water heaters in series
Range Boiler Water Heaters
Side Arm Coil Water Heaters
Solar Water Heaters
Tankless Coil for Hot Water
Tankless Water Heaters
Guide to Tankless Water Heaters
Operation & Characteristics
Problems & Defects
Hot Water Delivery Speedup
Installation Requirements & Costs
Should I Convert to a Tankless Heater?
Calculate Water Heater Requirements
Capacities of Tankless Water Heaters
Life Expectancy & Applications
- Thanks to Arlene Puentes for photographs of a variety of electric shower heaters in use in Puerto Rico and for technical contribution to this article - 03/26/2009. Arlene Puentes is a licensed home inspector, past chapter president of the Hudson Valley chapter of the American Society of Home Inspectors, an educator, and building failures researcher in Kingston, NY who can be reached at ap@octoberhome.htm or at 845-339-7984. Ms. Puentes website www.octoberhome.com contains additional information.
- Dur-o-Matic point of use electric shower heaters - Duromatic of Puerto Rico Inc - Rio Piedras, Puerto Rico, 787-764-4490
- Marey electric point of use shower heaters: http://www.marey.com/english_/home.htm "Marey electric shower water heaters are installed directly on the shower water pipe. These heaters are commonly used where central hot water is not available."
- Marey electric point of use shower heaters (and also Marey propane gas tankless water heaters) are distributed in North America by Mark Brant at www.tanklesshq.com where you can view their Marey electric shower water heaters at http://tankless-water-heaters.ecrater.com/category.php?cid=292215
- Stiebel Eltron Tankless Water Heaters - http://www.stiebel-eltron-usa.com/
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
- Our recommended books about building design, inspection, and repair, and about indoor environment testing, diagnosis, and cleanup are at the InspectAPedia Bookstore.
- ...
More Information on Building Diagnostic Inspections and Repairs
-
...
 InspectAPedia® Home & Site Map - Building & Environmental Inspection, Testing, Diagnosis, Repair, & Problem Prevention Advice: In-depth research & advice on diagnosing, testing, correcting, & preventing building defects & indoor environmental hazards. Unbiased information, no conflicts of interest. |
 The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems |
 Use this simple, economical mold test kit by following our instructions on how to collect and mail mold samples to our lab |
|
Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.
|
 Building Inspection, Problem Diagnosis, Forensic Investigation & Testing, Repair Consulting |
|
|
