STIEBEL ELTRON DHC-E 20 User manual

DHC-E 20, DHC-E 30
DHC-E TANKLESS ELECTRIC WATER
HEATERS INSTALLATION INSTRUCTIONS
FOR THE LICENSED PLUMBER AND
ELECTRICIAN
Table of contents
Temperature increase above ambient water temperature….. 2
General…………………………………………………………… 6
Mounting the unit …………………………………………………6
Water connections……………………………………………….. 6
Electrical connections…………………………………………… 7
Putting the water heater into operation……………………….. 7
Normal maintenance……………………………………………..7
Technical Data……………………………………………………7
Troubleshooting…………………………………………………..8
Spare parts………………………………………………………..8
Warranty…………………………………………………………...8

Maximum temperature increase above ambient water
temperature

Legend to figures
1 Temperature adjustment knob
2 Temperature display
3 "Power" light
4 Hot water connection
5 Cold water connection
6 Wiring block
7 Electronic control unit
8 Safety thermal cut out
9 Heating system
10 Knock-outs for wires
11 Water supply line for faucet
installation
12 Sink
13 Cold valve (right)
14 Hot valve (left)
15 Screws and plastic wall
anchors
General
The DHC-E 20 and DHC-E 30 are
designed to supply hot water for a
house or apartment. Unlike a
conventional storage type water
heater the DHC-E tankless water
heater does not store hot water.
Instead, water is heated
instantaneously as it flows
through the unit. Due to the
absence of stand-by losses, the
DHC-E offers greater energy
efficiency than storage type water
heaters.
The input of heat into the water is
controlled electronically. The
DHC-E will deliver any water
temperature between 86 ºF (30
ºC) and 125 ºF (52 ºC). Please
set the desired temperature using
the knob on the front cover. The
LED displays the temperature
that the unit will produce in °C.
Please use the conversion table
on the unit in order to obtain
degree Fahrenheit. The maximum
temperature is electronically
limited to 125 °F (52 °C).
In case the “Power” light is
flashing while the unit operates,
the water flow rate exceeds
the heating capacity of the unit.
Reduce the hot water flow rate in
order to let the unit achieve the
set point temperature. In case you
have questions regarding the way
you plan to use the DHC-E,
please call our technical service
line at 800-582-8423 (USA
and Canada). For service outside
the U.S. and Canada, please call
us at USA 413-538-7850. You
can also e-mail us at
[email protected] or
fax us at USA 413-538-8555.
One DHC-E can be used for the
following applications.
(C)1 Typical residential
installation
(C)2 Typical commercial
installation
Mounting the unit
UNIT MUST BE INSTALLED IN
A VERTICAL POSITION WITH
THE WATER FITTINGS
POINTING DOWNWARD.
DO NOT INSTALL UNIT
WHERE IT WOULD ROUTINELY
BE SPLASHED WITH WATER.
ELECTRIC SHOCK MAY
RESULT.
1. Install DHC-E as close as
possible to the main hot water
draw-off points.
2. Install DHC-E in a frost free
area. If frost may occur, remove
unit before freezing temperatures
set in.
3. Leave a minimum of 5" of
clearance on all sides for
servicing.
4. Remove the cover (D) .
5. Mount unit securely to wall by
putting four screws through
mounting holes (E) .
Screws and plastic wall anchors
for mounting on masonry or wood
are provided.
Water connections
1. All plumbing work must comply
with national and applicable state
and local plumbing codes.
2. A pressure reducing valve must
be installed if the cold water
supply pressure exceeds
150 PSI (10 bar).
3. Make certain that the cold
water supply line has been
flushed to remove any scale
and dirt.
4. An isolating valve is an integral
part of the cold water inlet. This
valve allows the unit to be isolated
for maintenance purposes.
5. The cold water connection
(inlet) is on the right side of the
unit, and the hot water
connection (outlet) is on the left
side of the unit.
NOTE: EXCESSIVE HEAT
FROM SOLDERING ON
COPPER PIPES NEAR THE
DHC-E MAY CAUSE DAMAGE.
6. Tankless water heaters such as
the DHC-E are not required to be
equipped with a Pressure and
Temperature Relief Valve
(P&T). If the local inspector will
not pass the installation without a
P&T, it should be installed on the
hot water outlet side of the unit.
7. The DHC-E is designed for
connection to copper tubing, PEX
tubing or a braided stainless steel
hose with a 3/4. NPT female
tapered thread. If soldering near
the unit is necessary, please
direct the flame away from the
housing of the unit in order to
avoid damage.
8. When all plumbing work is
completed, check for leaks and
take corrective action before
proceeding.

Electrical
connection
WARNING: BEFORE
BEGINNING ANY WORK ON
THE ELECTRIC INSTALLATION,
BE SURE THAT MAIN
BREAKER PANEL SWITCHES
ARE “OFF” TO AVOID ANY
DANGER OF ELECTRIC
SHOCK. ALL MOUNTING AND
PLUMBING MUST BE
COMPLETED BEFORE
PROCEEDING WITH
ELECTRICAL HOOK-UP.
WHERE REQUIRED BY LOCAL,
STATE OR
NATIONAL ELECTRICAL
CODES THE CIRCUITS
SHOULD BE EQUIPPED WITH
A “GROUND FAULT
INTERRUPTER”.
1. All electrical work must comply
with national and applicable state
and local electrical codes.
2. The DHC-E should be
connected to properly grounded
dedicated branch circuits of
proper voltage rating. Ground
must be brought to the .Ground.
at the circuit breaker panel. The
DHC-E 20 and DHC-E 30 must
have multiple power sources G .
A DHC-E 20 requires two
independent circuits. Use two
AGW # 8 supply cables
protected by two separate double
pole 50 Amp. breakers (see (1).)
A DHC-E 30 requires three
independent circuits. Use three
AGW # 8 supply cables
protected by three separate
double pole 50 Amp. breakers.
In both cases, make sure that the
unit is properly grounded
(see (2).) Please refer to the
technical data table for the correct
wire and circuit breaker size.
3. The wire must be fed through
the knockouts located between
the hot and cold water
connections F . The “live” wires
must be connected to the slots on
the terminal block marked Land
L. The ground wire must be
connected to slot marked
with the ground symbol.
4. Reinstall the cover with screws.
WARNING: AS WITH ANY
ELECTRIC APPLIANCE,
FAILURE TO ELECTRICALLY
GROUND UNIT MAY
RESULT IN SERIOUS INJURY
OR DEATH.
Putting the water
heater into
operation
WARNING: OPEN HOT WATER
FAUCET FOR A FEW MINUTES
UNTIL WATER FLOW IS
CONTINUOUS AND ALL AIR IS
PURGED FROM WATER
PIPES. THE UNIT’S COVER
MUST BE INSTALLED BEFORE
THE CIRCUIT BREAKERS ARE
TURNED ON.
1. Turn on circuit breakers to
bring electrical power to the unit.
2. Adjust the water temperature to
the desired level using the knob
on the front cover of the unit. The
DHC-E displays the temperature
in degree Celsius. There is a
conversion table on the front
cover that helps to convert from
degree Celsius to degree
Fahrenheit.
3. Turn on hot water and wait
twenty seconds until temperature
has stabilized.
4. Check the water temperature
with your hand and make sure
that it does not feel too hot.
Reduce if necessary.
5. Explain to the user how the unit
works and familiarize him or her
with its use. Advise the user about
possible hazards (hot water
temperature up to 125 °F /
52 °C). Hand over these
instructions, to be kept for future
reference.
Normal
Maintenance
STIEBEL ELTRON DHC-E
tankless water heaters are
designed for a very long service
life. Actual life expectancy will
vary with water quality and use.
The unit itself does not require
any regular maintenance.
However, to ensure consistent
water flow, it is recommended to
periodically remove scale and dirt
that may build up at the aerator of
the faucet or in the shower head.
Also, the DHC-E has a built in
filter screen that should be
cleaned from time to time. In
order to do this, turn off the cold
water supply at the isolating valve
and remove the cap of the filter
screen (H) . Clean screen
and put the screen and cap back
into their original position.
OTHER THAN THE FILTER
SCREEN, THE DHC-E DOES
NOT CONTAIN ANY PARTS
SERVICEABLE BY THE LAY
PERSON. IN CASE OF
MALFUNCTION PLEASE
CONTACT A LICENSED
PLUMBER OR ELECTRICIAN.