STIEBEL ELTRON Accelera 300 Specification sheet

OPERATING AND INSTALLATION MANUAL
DHW HEAT PUMP WATER HEATER
» ACCELERA© 300
A 280011-35603-85xx B 289230-35603-85xx
STIEBEL ELTRON Inc.
17 West Street | West Hatfield MA 01088
Tel. [phone] | Fax [phone]
Email [e-mail]
www.stiebel-eltron-usa.com

2 | ACCELERA 300 WWW.STIEBEL-ELTRON-USA.COM
GENERAL INFORMATION
GENERAL INFORMATION
Please read Read these instructions carefully and retain
them for future reference. If the water heater
is passed on to a third party please hand these
instructions to the new user.
This manual includes important information regarding
the safe and efficient handling of the water heater.
The manual is part of the water heater and should be
retained in the immediate vicinity and should always
be accessible.
The steps described must only be carried out by a
licensed installer. The respective licensed installer must
read these instructions prior to commencing any work. It
is imperative for safe working that all safety instructions
and actions described are complied with. In addition,
all local and national accident prevention and general
safety instructions apply.
Should safety instructions be ignored, the water heater
may not operate correctly or material losses may occur.
Serious injury or death may result. Never remove the
water heater casing without first isolating the water
heater from its power supply.
Illustrations in these instructions are designed to aid a
general understanding and may deviate from the actual
water heater version. No claims can be derived from
such illustrations.
Limited liability:
We have collated all details and information in this
manual in due consideration of applicable standards
and regulations, the state of the art and our long-term
know-how and experience.
Losses due to the following are excluded from our
liability:
- Non-observance of these instructions
- Incorrect use
- Installation of the water heater by unqualified
personnel
- Unauthorized modifications
- Technical modifications
- Use of unauthorized spare parts
Copyright:
These operating and installation instructions are subject
to copyright.
Transferring these instructions to third parties, copying
of any kind, either in total or extracts therefrom, as well
as their use and/or conveying its contents are prohibited
without our written consent.
Contraventions are liable to claims for compensation.
Further claims are reserved.
We hold the copyright:
STIEBEL ELTRON Inc.
17 West Street | West Hatfield MA 01088
Tel. [phone] | Fax [phone]
Email [e-mail]
www.stiebel-eltron-usa.com
Should you have any question regarding the installation
or operation of the water heater, please contact our
customer service. Tel. (USA) 800-582-8423 or 413-247-
3380

ENGLISH
WWW.STIEBEL-ELTRON-USA.COM ACCELERA 300 | 3
CONTENTS | OPERATION
GENERAL INFORMATION _______________________________ 2
OPERATION _____________________________________________ 4
1. Overview_________________________________________ 4
2. General information _____________________________ 4
2.1. Key to symbols___________________________________ 4
3. Safety_____________________________________________ 8
3.1. General safety instructions ____________________ 8
3.2. Intended use _____________________________________ 8
3.3. Incorrect use _____________________________________ 8
3.4. Personnel qualification_________________________ 8
3.5. Safety equipment _______________________________ 8
3.6. Particular risks___________________________________ 9
4. Water heater description _______________________ 9
4.1. Function description____________________________ 9
5. Operation for installers and homeowners____ 10
5.1. Start-up by a licensed installer ______________ 10
5.2. Starting and stopping _________________________ 10
5.3. Emergency stop ________________________________ 10
6. Maintenance and care__________________________ 10
6.1. Descaling ________________________________________ 11
7. What to do if ... _________________________________ 11
7.1. ... the water heater does not deliver hot
water _____________________________________________ 11
7.2. ... the safety valve of the cold water supply
line is dripping__________________________________ 11
7.3. ... the condensate drain drips________________ 11
7.4. ... the power consumption is too high _____ 11
7.5. ... the room temperature drops excessively
____________________________________________________ 11
7.6. ... other faults occur ___________________________ 11
8. Safety____________________________________________ 12
8.1. General safety instructions ___________________ 12
8.2. Incorrect use ____________________________________ 12
8.3. Qualification_____________________________________ 13
8.4. Instructions, standards and regulations ___ 13
8.5. Water installation ______________________________ 13
8.6. Electrical installation __________________________ 13
9. Water heater description ______________________ 14
9.1. Standard delivery ______________________________ 14
9.2. Special accessories_____________________________ 14
10. Installation ______________________________________ 15
10.1. Installation location____________________________ 15
10.2. Shipping inspection____________________________ 15
10.3. Handling _________________________________________ 16
10.4. Storage ___________________________________________ 16
10.5. Positioning the water heater _________________ 16
10.6. Unpacking the water heater__________________ 17
10.7. Water connection_______________________________ 19
10.8. Power supply ___________________________________ 20
11. Start-up _________________________________________ 22
11.1. Start-up __________________________________________ 22
11.2. Shutting down __________________________________ 22
11.3. Start-up after shut down _____________________ 22
12. Settings _________________________________________ 23
12.1. Adjusting the water temperature ___________ 23
13. Before the licensed installer leaves___________ 23
14. Troubleshooting ________________________________ 23
14.1. Safety equipment of the water heater______ 23
14.2. Troubleshooting ________________________________ 24
15. Maintenance and cleaning _____________________ 24
15.1. Cleaning the evaporator ______________________ 24
15.2. Draining the tank_______________________________ 24
15.3. Sacrificial anode________________________________ 25
15.4. Descaling ________________________________________ 25
15.5. Checking valves_________________________________ 25
16. Specification ____________________________________ 26
16.1. Connection and other dimensions __________ 26
16.2. Wiring diagram_________________________________ 27
16.3. Refrigerant diagram ___________________________ 28
16.4. Data table________________________________________ 29
WARRANTY ____________________________________________ 31
ENVIRONMENT AND RECYCLING______________________ 31

OPERATION
OVERVIEW
4 | ACCELERA 300 WWW.STIEBEL-ELTRON-USA.COM
1. Overview
Front of the water heater
7
62
5
43
1
26_03_01_0880
44
1 Water heater cover
2 Opening for PT valve
3 Condensate drain
4 Leveling feet
5 Cold water inlet
6 Hot water outlet
7 Air entry
The water heater extracts heat from the ambient air and
utilizes this energy to heat hot water.
An 80 gallon water tank is part of the water heater. Foam
insulation is applied to the outside of the water tank to
prevent heat losses. The water heater casing is made
from powder-coated sheet steel.
The internally enameled water tank is supported by
three height-adjustable anti-vibration leveling feet.
OPERATION
Back of the water heater
89
26_03_01_0880
8 Air discharge
9 Cable entry for the power cable
2. General information
The chapter Operation is intended for users and licensed
installers.
The chapter Installation is intended for licensed
installers only.
2.1 Key to symbols
2.1.1 Layout of safety information
DANGER Electric shock Before any work on the water
heater, disconnect all poles from
the power supply.
13
4
2
1 Symbol (see chapter "Symbols")
2 Keyword (see chapter "Keywords")
3 Designations (see chapter "Symbols")
4 Information text

OPERATION
GENERAL INFORMATION
ENGLISH
WWW.STIEBEL-ELTRON-USA.COM ACCELERA 300 | 5
2.1.2 Symbols
Symbol Description
Injury
Electrocution
Burns or scalding
!Other situations
Fire
Explosion
Water heater disposal
2.1.3 Keywords
KEYWORD
DANGER The keyword DANGER indicates
information that must be observed,
otherwise serious injury or death
will result.
WARNING The keyword WARNING indicates
information that must be observed,
otherwise serious injury or death
may result.
CAUTION The keyword CAUTION indicates
information that must be observed,
otherwise relatively serious or light
injuries may result.
2.1.4 Symbols in this documentation
Read the text next to this symbol carefully.
»Passages with the symbol "»" indicate that you have
to do something. The action you need to take is
described step by step.
- Passages with this symbol "–" indicate lists.
2.1.5 Units of measure in this documentation
The dimensions in this document are given in inch (millimeters).
2.1.6 Information on the packaging
Information label "Top heavy"
AO 085 / Created with Adobe Illustrator CS
Benennung:
Description:
Mat.Nr.:
Ident.No.:
Bearb.:
Editor:
Gepr.:
Checked:
Datum:
Date:
Änd.-Index:
Mod.-index:
Datum:
Date:
Datum:
Date:
Ersatz für:
Substitute:
V / ZV:
Manifold.:
Format:
Size:
Maßstab
Measuring rod:
Blatt:
Page:
Herausgabe Index:
Actual Index:
Materialart:
Type of material:
Klassifizierung:
Classification:
Für diese Zeichnung behalten wir uns alle Rechte vor. Schutzvermerk nach
DIN ISO 16016 beachten. Änderungen von Seiten des Lieferanten bedürfen
der vorherigen Genehmigung durch STIEBEL ELTRON
For this drawing we reserve ourselves all rights to protection note
DIN ISO 16016 pay attention. Change from the supplier need the previous
approval by STIEBEL ELTRON.
Herstellnummer:
Date of manufacturing:
Lfd. Nummerierung / Start:
Upcounting number / Start:
Material:
Material:
Norm gepr.:
Norm check:
Roh
1 / 1
A3
1 : 1
EWN 801
000001
165123
264623
Afkl Hinw Transport
Haibach
Hoersting
__
28.06.04
28.06.04
_
K_______.__.__
20 / 15
K33631
23700000
Transportation Information Sticker
! !
Hoher Schwerpunkt
High balance point
Hoog zwaartepunt
Centre de gravité en partie haute
Hög tyngdpunkt
Alto centro di graviá
Alto centro de gravedad
Achtung - Attention - Attentie - Attention
Uppmärksamhet - Oppmerksomhet
Attenzione - Atención
264623/K33631
264623-33631
Information label "Vertical transport"
! Achtung - Attention !
Transport und Aufstellung
Damit das Gerät vor Beschädigungen geschützt ist, sollte es bis an den Montageort in der Verpackung transportiert werden. Gerät senkrecht transportieren! Bei
beengten Transportbedingungen kann das Gerät auch kurzzeitig geneigt werden. Beachten Sie die weiteren Hinweise zum Aufstellen und Ausrichten des Gerä-
tes in der beiliegenden Gebrauchs- und Montageanweisung um Schäden am Gerät zu vermeiden.
Transport and installation
To protect the equipment against damage, it must be transported inside its dedicated packaging until the installation facility is arrived. Transport the equipment
upright. Where space is restricted, you may also move briefly the equipment tipped backwards at an angle.. Observe the notes on installation and fitting of the
equipment, which can be found in the enclosed installation and operating instructions, to avoid possible damage to the equipment.
280306-34594
Gerät nur senkrecht oder ggf. geneigt transportieren.
Move this machine only in a vertical position or, if required, slightly inclined with the control facia point up.
280306-34594

OPERATION
GENERAL INFORMATION
6 | ACCELERA 300 WWW.STIEBEL-ELTRON-USA.COM
1 Information label "Condensate drain"
This label shows you the position where the water
heater drain is located.
Drain
280302-3481284594
280302-34812.
2 Information label "Risk of scalding"
BURN
HOT
CAUTION
DANGER
!
284760-34684
284760-34684.
3 Information label "Connection"
For reason
of
corrosion
protection
use flat
gasket ring
280305-34625
280305-34625
2.1.7 Information on the water heater
BURN
HOT
CAUTION
DANGER
!
284760-34684
Forreason
of
corrosion
protection
useflat
gasketring
280305-34625
WW Austritt
DHW outlet
280304-34
6845
Warning
Atemperature and pressure relief valve
mustbe fitted to the clearly marked
socket.The valve drain outlet pipe
mustnot be sealed or blocked, and the
valveeasy gear is to be operated
atleast once every six month.
280558-34684
Relief valve
Plumber:
Therelief valve supplied in the
cartonmust be fitted to this
socket.
280557-34684
Forreason
of
corrosion
protection
use flat
gasketring
280305-34625
Drain
28030
2-3481284594
KW Eintritt
CW Inlet
280303-346845
4
26
17
3
5
26_03_01_1355
3
1 Information label "Condensate drain"
2 Information label "Risk of scalding"
3 Information label "Connection"
4 Information label "Hot water outlet"
5 Information label "Relief valve"
6 Information label "Relief valve installation location"
7 Information label "Cold water inlet"
Power supply
Disconnectpower supply
beforeopening the cover.
280556-3468425
Type:Accelera300/WHP300
Heatpump:
PN(Air42°/Water 60°):
IN(Air42°/Water 60°):
TypeofRefrigerant:
Refrigerantcharge:
Max.operatingpressure:
Lockrotorcurrent:
MCA:
Ratedloadcompressor:
Motorfan:
Order-No.:222423
DHW-cylinder:
Additionalheatingelement:
Max.operatingpressure:
Max.operatingtemperature:
Typeofcylindermaterial:
Cylindercapacity:
Testpressurestoragetank:
Observetheinstallationmanual! Tested for leaks!
MadeinGermany
No.: 8443 / 005204
Voltage/Frequency:
Breaker:
P (ratedpowerinput):
Maximumallowableratings
Protectionclass:
Nmax
Singlephase220-240V, 50/60 Hz
15amp.
2200W,9.17A
IP24
*222423844300520415*
1690W
87psi/600kPa
168.8°F/76°C
Glasslinedsteel
80.044Gal/303l
130.5psi/900 kPa
0.5kW
2.17A
R134A
1.9842Lb./900g
348.1psi/2.4MPa
13.4A
10.4A
2.3A
38W
STIEBELELTRONINC
17WestStreet
WestHatfield,MA01088
USA
282209-35237
DE:EnthältvomKyoto - Protokoll erfasste fluorierte Treibhausgase - hermetisch geschlossenes System .
GB:Containsfluorinatedgreenhouse gases covered by the Kyoto Protocol - her meticallysealed.
FR:Comprendlesgaz à effet de serrefluorés enregistrés par le proto cole de Kyoto - systèmes hermétiquement scellés.
NL:Bevatgefluoreerdebroeikasgassen die onder het Kyoto-protocol vallen - herme tischgeslotensysteem.
SE:InnehålleravKyoto - protokollet registrerade flourerande växthusgaser i hermetiskt förslutna sys tem.
PL:Zawierafluorowanegazy cieplarniane ujęte w Protokole z Kioto - hermetycznie zamkni ęty układ.
CZ:Obsahujefluorizovanéskleníkové plyny, obsažené v Kjótském protokolu - herm etickyuzavřenýsystém.
ES:Sistemaherméticamentecerrado que contiene gases de efecto invernader o mencionados en el protocolo de Kioto.
DK:IndeholderfraKyoto-protokollenregistrerede, fluorerede drivhusgasser – hermetisk lukket system .
NO:Inneholderfluorertedrivhusgassersom omfattes av Kyotopro tokollen-hermetisklukket system.
FI:SisältääKiotonsopimuksen alaisia fluorattuja kasvihuonekaasuja - ilmatiiviisti suljettu järjestelmä. 284436-34741
BG:СъдържапосоченитевПротоколаот Киото флуорирани парникови газове - херметически затворена система.
HU:AKiotóiJegyzıkönyv szerinti fluortartalmú üvegházhatású gázokat tartalmaz - hermetikusan zárt rendszer.
IT:Contienegasfluorurati ad effetto serra disciplinati dal protocollo di Kyoto- Impianto ermeticamente chius.
RO:Conțineunsistem închis ermetic contra emisiei de gaze fluorine monitorizat de protocolul Kyoto.
8
11
26_03_01_1356
10
9
8 Information label "Power connection"
9 Type plate
10 Information label "Fluorated gases"
11 Information label "Energy efficiency"

OPERATION
GENERAL INFORMATION
ENGLISH
WWW.STIEBEL-ELTRON-USA.COM ACCELERA 300 | 7
4 Information label "Hot water outlet"
WW Austritt
DHW outlet
280304-34
6845
280304-34684
5 Information label "Relief valve"
Warning
A temperature and pressure relief valve
must be fitted to the clearly marked
socket. The valve drain outlet pipe
must not be sealed or blocked, and the
valve easy gear is to be operated
at least once every six month.
280558-34684
280558-34684
6 Information label "Relief valve installation location"
Relief valve
Plumber:
The relief valve supplied in the
carton must be fitted to this
socket.
280557-34684
280557-34684
7 Information label "Cold water inlet"
KW Eintritt
CW Inlet
280303-34
6845
280303-34684
8 Information label "Power connection"
Power supply
Disconnect power supply
before opening the cover.
280556-34
68425
280556-34684
9 Type plate
Type: Accelera 300/WHP 300
Heat pump:
PN (Air 42°/ Water 60°):
IN (Air 42°/ Water 60°):
Type of Refrigerant:
Refrigerant charge:
Max. operating pressure:
Lock rotor current:
MCA:
Rated load compressor:
Motor fan:
Order-No.: 222423
DHW-cylinder:
Additional heating element:
Max. operating pressure:
Max. operating temperature:
Type of cylinder material:
Cylinder capacity:
Test pressure storage tank:
Observe the installation manual! Tested for leaks!
Made in Germany
No.: xxxx / xxxxxx
Voltage / Frequency:
Breaker:
P(rated power input):
Maximum allowable ratings
Protection class:
Nmax
Single phase 220-240 V, 50/60 Hz
15 amp.
2200 W, 9.17 A
IP 24
*222423xxxxxxxxxxxx*
1690 W
87 psi /600kPa
168.8 °F / 76 °C
Glass lined steel
80.044 Gal /303l
130.5 psi / 900 kPa
0.5 kW
2.17 A
R134A
1.9842 Lb. /900g
348.1 psi /2.4 MPa
13.4 A
10.4 A
2.3 A
38 W
STIEBEL ELTRON INC
17 West Street
West Hatfield, MA 01088
USA
282209-35237
26_03_01_1357
10 Information label "Fluorated gases"
DE: Enthält vom Kyoto - Protokoll erfasste fluorierte Treibhausgase - hermetisch geschlossenes System.
GB: Contains fluorinated greenhouse gases covered by the Kyoto Protocol - hermetically sealed.
FR: Comprend les gaz à effet de serrefluorés enregistrés par le protocole de Kyoto - systèmes hermétiquement scellés.
NL: Bevat gefluoreerde broeikasgassen die onder het Kyoto-protocol vallen - hermetisch gesloten systeem.
SE: Innehåller av Kyoto - protokollet registrerade flourerande växthusgaser i hermetiskt förslutna system.
PL: Zawiera fluorowane gazy cieplarniane ujęte w Protokole z Kioto - hermetycznie zamknięty układ.
CZ: Obsahuje fluorizované skleníkové plyny, obsažené v Kjótském protokolu - hermeticky uzavřený systém.
ES: Sistema herméticamente cerrado que contiene gases de efecto invernadero mencionados en el protocolo de Kioto.
DK: Indeholderfra Kyoto-protokollen registrerede, fluorerede drivhusgasser – hermetisk lukket system.
NO: Inneholderfluorerte drivhusgasser som omfattes av Kyotoprotokollen - hermetisk lukket system.
FI: Sisältää Kioton sopimuksen alaisia fluorattuja kasvihuonekaasuja - ilmatiiviisti suljettu järjestelmä. 284436-34741
BG: Съдържа посочените вПротокола от Киото флуорирани парникови газове - херметически затворена система.
HU: A Kiotói Jegyzıkönyv szerinti fluortartalmú üvegházhatású gázokat tartalmaz - hermetikusan zárt rendszer.
IT: Contiene gas fluorurati ad effetto serra disciplinati dal protocollo di Kyoto - Impianto ermeticamente chius.
RO: Conține un sistem închis ermetic contra emisiei de gaze fluorine monitorizat de protocolul Kyoto.
26_03_01_1386
11 Information label "Energy efficiency"
282980-34625
Maintain the legibility of all information labels. Illegible safety information and symbols can
result in dangerous situations.

OPERATION
SAFETY
8 | ACCELERA 300 WWW.STIEBEL-ELTRON-USA.COM
3. Safety
This chapter provides an overview of all important
actions required for a safe and trouble-free operation.
3.1 General safety instructions
Operate the water heater only when fully installed and
with all safety equipment fitted.
Unsuitable tools or incorrect handling of the water
heater can result in damage to the water heater and
to water or refrigerant leaking from the water heater.
DANGER Scalding
The water is heated inside the water tank to
140 °F(60 °C). There is a risk of scalding at
outlet temperatures above 109 °F (43 °C).
»Ensure that outflowing water does not
directly contact your body.
CAUTION Injury
Where children or persons with limited
physical, sensory or mental capabilities are
allowed to control this water heater, ensure
that this will only happen under supervision
or after appropriate instruction by a person
responsible for their safety.
»Children should be supervised to ensure
that they never play with the water heater.
Never place any objects on top of the water heater.
Objects placed on top of the water heater
can increase the noise level developed by the
water heater through vibrations.
Never cover the water heater.
The water heater draws in air. Covering the
inlet slots reduces the air intake. This reduces
the efficiency of the water heater and can even
lead to one of the safety facilities interrupting
the water heater operation.
3.2 Intended use
This water heater produces hot water automatically.
The water heater can be installed and operated in the
open as well as in enclosed spaces. The temperature of
the air that is drawn in during operation must not fall
below 43 °F(6 °C).
Any other use beyond that described shall be deemed
inappropriate. Observation of these instructions is also
part of the correct use of this water heater.
Any changes or modifications to this water heater void
all warranty rights.
3.3 Incorrect use
The following are not permitted:
- Do not use heating media other than potable water
- Do not use uqualified (unlicesensed) personnel for
installation
- Do not use in an environment with greasy extract
air
This water heater must not be operated at ambient temperatures in excess of 107 °F
(42°C) or below 43°F (6 °C).
If outside air is directly drawn in ensure, that
the water heater is isolated from its power
supply when the air temperature falls below
43 °F(6 °C).
3.4 Personnel qualification
DANGER Injury
Incorrect handling can result in severe injuries
and material losses. Inadequately qualified
personnel cannot assess the impending
danger.
Have the installation, commissioning,
maintenance and repair steps carried out only
by the qualified individuals specified in the
respective chapters.
In the remainder of this manual, such qualified
individuals will be described as the "licensed installer."
3.5 Safety equipment
Wear safety shoes/boots during the transportation and
positioning of the water heater. Dry, this water heater
weighs 290 lb (130 kg.) Safety shoes/boots reduce the
risk of contusions.

OPERATION
WATER HEATER DESCRIPTION
ENGLISH
WWW.STIEBEL-ELTRON-USA.COM ACCELERA 300 | 9
3.6 Particular risks
3.6.1 Electric current
WARNING Electric shock
Contacting parts that carry live power is
associated with a direct risk to life. Damaging
the insulation or individual components can
result in a risk to life.
»If you detect damaged insulation,
immediately switch off the power supply
and arrange for the necessary repair.
»Have all electrical work carried out by a
qualified electrician.
3.6.2 Hot surfaces
CAUTION Burning
Contact with hot components can result in
burning.
»When working near hot components, wear
protective clothing and gloves.
»The pipework connected to the hot water
outlet of the water heater can reach
temperatures in excess of 140 °F (60°C).
3.6.3 Refrigerant
The water heater is filled with refrigerant at the factory.
WARNING Freezer burn
Should the water heater leak refrigerant,
avoid contact with the refrigerant or
breathing in any released vapors. Vent the
room concerned.
In normal water heater operation, the refrigerant is
contained in a sealed circuit, hence no risk arises from
the refrigerant.
4. Water heater description
This water heater is an automatic hot water generator
with approx. 80 gallon capacity. The hot water
temperature is factory set to 140 °F (60 °C).
After opening a hot water faucet, the hot water is pushed
out of the water heater by the incoming cold water.
The water heater operates with recirculating air and
consequently requires no outside air supply. The water
heater extracts heat from the ambient air. This heat
is used to heat the water contained inside the tank;
simultaneously electrical energy is used. The demand
for electrical energy and the heat-up time depend on
the temperature of the air drawn in.
When installing the water heater inside, the room where
it is installed will be cooled down during the operation
by 2 to 6 °F (1 to 3 °C).
The water heater also extracts moisture from the air
that creates condensate, which must be drained off. For
this purpose, a condensate drain with strainer plug is
integrated in the bottom of the water heater. This is
where you can connect a hose.
To protect the steel tank against corrosion, the interior
is coated with a special enamel and is furthermore
equipped with a sacrificial anode.
Heat pump function:
A sealed circuit inside the water heater contains a CFC-
free refrigerant (see "Specification/data table"); this does
not deplete ozone and is non-flammable. It evaporates
at low temperatures.
In the evaporator, where heat is extracted from the
outside air, the refrigerant changes from its liquid into
its gaseous state. A compressor draws the process
medium in and compresses it. The increase in pressure
raises the refrigerant temperature.
This process requires electrical energy. The energy
(motor heat) is not lost, but reaches the condenser
downstream together with the compressed refrigerant.
Here, the process medium transfers heat to the water
tank. An expansion valve then reduces the still prevalent
pressure and the circular process starts again.
4.1 Function description
4.1.1 Heat pump operation
In heat pump mode, the heat pump unit located in
the upper section of the water heater extracts heating
energy from the ambient air.
This is the standard operating mode, which can be
used within the limits of scope of the water heater (see
chapter "Specification/data table").
If the water heater was separated from the power supply during operation, the
compressor will only restart if the pressure inside
the refrigerant circuit has been balanced. Pressure
balance can only be created after three minutes.

OPERATION
OPERATION
10 | ACCELERA 300 WWW.STIEBEL-ELTRON-USA.COM
4.1.2 Booster heater
Primarily, the water inside the tank is heated by the
heat pump.
When there is a higher hot water demand or when the
water heater was switched OFF for a longer period and
you require hot water quickly, you can accelerate the
heat-up process by means of the integral booster heater.
For energy saving reasons, the booster heater only heats
the top third of the tank (approx. 27 gallons).
A thermostat switches the booster heater on, if the water
temperature inside the tank falls below 112 °F (45 °C). A
thermostat switches the booster heater off, if the water
temperature inside the tank exceeds 140 °F (60 °C).
4.1.3 Defrosting
The lower limit of use of the water heater is permanently
set to 42 °F (6 °C). It is possible that at this limit, the
evaporator will be coated in frost. This is subject to the
air temperature and humidity level, particularly at low
hot water temperatures.
The compressor will be switched off as soon as the
evaporation temperature falls below 20 °F (-7 °C) for any
length of time. When the temperature at the evaporator
fins rises above 38°F (3°C), the compressor starts again,
and the hot water heating continues. The fan continues
to run during defrosting.
5. Operation
You do not have to make any adjustments. The water
heater is therefore not equipped with any controls. The
hot water temperature is permanently set to 140 °F
(60 °C).
Should you wish to operate with different settings,
contact your local licensed installer.
WARNING Scalding
The water is heated inside the water tank to
140 °F (60 °C). There is a risk of scalding at
outlet temperatures in excess of 108 °F (42 °C).
Ensure that outflowing water does not directly
contact your body.
5.1 Start-up by a licensed installer
The water heater is initially started up after the
installation by a licensed installer has been completed.
5.2 Starting and stopping
The water heater is not equipped with any ON/OFF
switch. If a power plug was fitted during installation, you
can disconnect the water heater from the power supply
by pulling that plug. Alternatively, you can terminate the
water heater operation by tripping the circuit breaker.
5.3 Emergency stop
In case of emergency, carry out the following steps:
»Isolate the power supply by tripping the circuit
breaker or by pulling the power plug that may have
been fitted during installation.
»Close the cold water inlet.
6. Maintenance and care
A damp cloth is sufficient for cleaning the water heater.
Never use abrasive or corrosive cleaning agents. Only
clean the water heater exterior. Never open the water
heater. Never spray the water heater with water.
»Monthly, check that the condensate drain in the
bottom of the water heater is not blocked by any
objects that may lie in front of the drain.
»Clean the strainer in the condensate drain at least
twice annually or subject to requirement. Sand and
dust can result in sludge building up inside the
strainer.
»Monthly, carry out a visual inspection of the
condensate pan drain (in the top of the water
heater; see the following diagram). For this, look
through the air intake grille at the front of the
water heater. If required, notify your local licensed
installer who will remove any contamination or
blockage.
1
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1 Condensate pan drain