Specification

Marathon
®
Specifications
Uniform Energy Factor and rated gallon capacity based on Department of Energy (DOE) requirements.
* This water heater is intended only for use as part of an electric thermal storage or demand response program. This water heater
will not provide adequate hot water unless enrolled in such a program and is activated by your utility company or another program
operator. Please confirm the availability of such a program in your local area before purchasing or installing this product.
Water heaters furnished with standard 240 or 120 volt AC, single phase non-simultaneous wiring. If heating elements of different
wattages than those shown are demanded, they must be specifically requested. For height to top of T&P and heat traps add
3-1/2” to the height to water connection.
Maximum test pressure: 300 PSI. Maximum working pressure: 150 PSI.
* *Recovery calculations used are based on 4500 watt elements used in non-simultaneous operation.
**Recovery = wattage/2.42 x temp. rise °F.
Example: 4500W = 21 GPH
2.42 x 90°
†
LEED Point = 1
Marathon
®
Point-of-Use Specifications
A
C
B
5-3/4"
3/4" NPT
C
B
5-3/4"
A
Fuel Type Description
Nominal
Gallon
Capacity
Rated
Gallon
Capacity
Model
Number
First Hour
Rating
G.P.H.
Recovery
In G.P.H.
90° F Rise
Tank
Height
A
Height to
Water Conn.
B
Diameter
C
Approx.
Ship Wt.
(LBS.)
Uniform
Energy Factor
(UEF)
Electric
Tall 30 28 MR30238C
†
41 12 49 49-1/2 21-5/8 75 0.92
Electric
Tall 30 28 MR30245C
†
43 20 49 49-1/2 21-5/8 75 0.92
Electric
Tall 40 38 MR40245C
†
51 21 61-1/2 65-1/2 21-3/4 90 0.92
Electric
Tall 50 50 MR50245C
†
57 21 62-3/4 66-3/4 23-1/2 100 0.92
Electric
Short 50 48 MSR50245C
†
53 21 43-1/4 47-1/4 28-1/4 95 0.92
Electric
Tall 100 101 MRG105245C* 85 21 66-3/4 70-3/4 30-1/4 152 0.92
Fuel Type Description
Nominal
Gallon
Capacity
Rated
Gallon
Capacity
Model
Number
Element
Wattage Voltage
Tank
Height
A
Height to
Water Conn.
B
Diameter
C
Approx.
Ship Wt.
(LBS.)
Uniform
Energy Factor
(UEF)
Electric
POU 15 N/A MR15120 2000 120 31-3/4 35-3/4 21-3/4 58 N/A
Electric
POU 19.9 N/A MR20120 2000 120 30-1/2 34-1/2 23-1/2 61 N/A
Electric
POU 19.9 N/A MR20230 3000 240 30-1/2 34-1/2 23-1/2 61 N/A
10/17 FORM NO. THD-ME Rev. 1
In keeping with its policy of continuous progress and product improvement, Rheem reserves the right to make changes without notice.
Rheem Water Heating • 1115 Northmeadow Parkway, Suite 100
Roswell, Georgia 30076 • www.rheem.com