A.O. Smith DRE 52 User manual

Innovation has a name.
DRE
Electric commercial
water heater
DRE - 52/80/120
Three phase electric water heater, primarily for commercial
applications•ThreetonineIncoloy-sheathedelementswitha
maximumratingof54kW•Eachelementisindependently
controlledviaitsowncontrolthermostat(adjustable:49-82°C)
andamanuallyresetablehigh-limitthermostat•Cascadecontrol
oftheelementsformoreefficientandfasterheating-uptimes
•Allelementsandthermostatsarefuse-protected•PermaGlas
UltraCoatsecond-generationglasscoatingtechnologyhelpsto
preventcorrosion•Replaceablemagnesiumanode•Safetyfloat
switch•Optionalancillaries:Unventedkits•Destratificationpump
kit•Poweredanodes•Timecontroller•AlternatekWloadings

DRE
Technical specifications
Electrical data
Input kW 9 18 36 9 18 36 54 9 18 36 54
Current A 11-13 23-25 46-50 11-13 23-25 46-50 69-75 11-13 23-25 46-50 69-75
Elements - 3 3 6 3 3 6 9 3 3 6 9
Powersupply VAC/Hz     415/50     
Draw-off capacity
Storage capacity l 200 300 450
Max.temperaturesetting °C 82 82 82 82 82 82 82 82 82 82 82
30 min. ∆T=44°C l 297 377 535 406 486 644 802 570 649 808 966
60 min. ∆T=44°C l 385 557 887 494 837 996 1330 658 825 1159 1494
90 min. ∆T=44°C l 473 728 1238 582 877 1348 1858 746 1001 1511 2021
120 min. ∆T=44°C l 561 904 1590 670 1013 1699 2385 834 1177 1863 2549
Continuous∆T=44°C l/h 176 352 704 176 352 704 1055 176 352 704 1055
Heating-uptime∆T=44°C min. 68 34 17 102 51 26 17 153 77 38 26
30 min. ∆T=50°C l 262 331 471 358 427 567 706 502 571 711 850
60 min. ∆T=50°C l 339 486 780 435 582 876 1170 579 726 1020 1314
90 min. ∆T=50°C l 416 641 1090 512 737 1186 1635 656 881 1330 1779
120 min. ∆T=50°C l 494 796 1399 590 892 1495 2099 734 1036 1639 2243
Continuous∆T=50°C l/h 155 310 619 155 310 619 929 155 310 619 929
Heating-uptime∆T=50°C min. 78 39 19 116 58 29 19 174 87 44 29
30 min. ∆T=55°C l 238 301 428 325 388 515 642 456 519 646 773
60 min. ∆T=55°C l 308 442 709 396 529 797 1064 526 660 927 1195
90 min. ∆T=55°C l 379 583 991 466 670 1078 1486 597 801 1209 1617
120 min. ∆T=55°C l 449 723 1272 536 811 1360 1908 667 942 1490 2039
Continuous∆T=55°C l/h 141 281 563 141 281 563 844 141 281 563 844
Heating-uptime∆T=55°C min. 85 43 21 128 64 32 21 192 96 48 32
General
Anodes -  2   2    2 
Maximum working pressure bar 8 8 8
Maximumweight kg  273   410    610  
Shipping data
Weightempty kg  73   110    160 
Weightincl.packaging kg  86   125    176 
Widthpackaging mm  630   700    890 
Heightpackaging mm  1640   1770    1760 
Depthpackaging mm  750   870    1050
DRE 52-9 DRE 52-18 DRE 52-36 DRE 80-9 DRE 80-18 DRE 80-36 DRE 80-54 DRE 120-9 DRE 120-18 DRE 120-36 DRE 120-54

DRE
Dimensions
DRE
Installation diagrams 1 Pressurereducingvalve
3 T&Pvalve
4 Stop valve
5 Non-returnvalve
6 Circulationpump
9 Drain valve
11 Isolating valve
14 Hot water outlets
15 Expansion relief valve
16 Expansion vessel
17Threewayvalve
18 Water tank
19 Float valve
A Coldwater
B Hot water
C Returncirculation
E Overflowpipe
H Expansion vent pipe
A.O. Smith unvented
system kits utilise
combination valves
Further installation and
connection details can be
found in the Installation
&CommissioningManual.
A   1465 1570 1610
B 1410 1530 1580
D   550 640 750
E 690 800 910
M 120 100 100
R 100 100 100
S 1210 1310 1380
1 Coldwater 11/4-14NPT
2 Hot water 11/4-14NPT
4 Tank drain valve 3/4-14NPT
5 T&Pvalve 3/4-14NPT
6 Anode connection Rp3/4
Dimensions in mm. All DRE water heaters receive a three years
warranty on the tank and one year on parts.
DRE 52 DRE 80 DRE 120
Vented
Unvented

www.aosmithinternational.com
Data subject to change INT/0808/DRE/01
Terms and conditions apply, please refer to our website.
A Main terminal
B Solenoid
D Overheat thermostat
E Electric element
H Float switch
K Safety relay
L Fuse
M Transformator
1 Black
2 Red
3 Blue
4 Brown
5 White
For the parts numbers of components
please refer to the “Maintenance and
accessories” chapter.
DRE
Electrical diagrams
3 elements
6 elements 9 elements