Technical Specifications
Essential
RichmondWaterHeaters.com
RICHMOND
®
 WATER HEATERS
In keeping with its policy of continuous progress and product improvement, Richmond reserves the right to make changes without notice.
Richmond Water Heaters • 1115 Northmeadow Parkway, Suite 100, Roswell, Georgia 30076
© Rheem Manufacturing Company • 
01/18
 • 
FORM NO. T-660 Rev. 2
Tankless Electric Specications
* 240V units can be used on 208V single phase with 25% reduced temperature output. Please note per UL standards the rating plate and installation instructions will all be according to a 240V 
applied voltage. Check with local ofcials prior to derating the electrical infrastructure.
  Rated Pressure  25 PSI min., 150 PSI max.
 Certications  ETL Listed to UL 499 and CSA
  Std. Temp. Settings  120°F (Adjustable 80°F-140°F)
  Temp. Accuracy  +/–1° at steady state ow
  Turn-On  0.3 GPM
PRODUCT
SPECIFICATIONS
(ALL MODELS)
RICHMOND PART 
NUMBER
GPM RATING OF 
INSERTS PROVIDED
CONNECTION 
SIZE
RTE10001A 1.0, 1.5, 2.0 1/2" NPT
RTE10001B 2.0, 3.0, 4.0, 5.0 3/4" NPT
OPTIONAL INLINE FLOW REGULATOR
• Enhanced outlet temperature control
• Install on the outlet side of the heater
• Limit maximum volume to the specied ow rate to ensure 
exiting temperature is within an acceptable range
• Flow Regulators for ½" and ¾" plumbing connections
• Flow range: 1 to 5 gallons per minute
SUGGESTED SIZING GUIDE
COLD CLIMATE 
(INLET TEMP. 
35-45°F)
WARM CLIMATE 
(INLET TEMP.
50-60°F)
HOT CLIMATE 
(INLET TEMP. 
65-75°F)
RMTEX-04 N/A N/A N/A
RMTEX-06 N/A N/A N/A
RMTEX-08 RTE10001A RTE10001A RTE10001A
RMTEX-11 RTE10001A RTE10001A RTE10001A
RMTEX-13 RTE10001A RTE10001A RTE10001A
RMTEX-18 RTE10001B RTE10001B RTE10001B
RMTEX-24 RTE10001B RTE10001B RTE10001B
RMTEX-27 RTE10001B RTE10001B RTE10001B
RMTEX-36 RTE10001B RTE10001B RTE10001B
Selection based on inlet temperature and an outlet temperature setting of 105°F
SUGGESTED SPECIFICATIONS 
Unit shall have copper clad immersion heating element(s) with 
brass terminations for increased durability. External temperature 
control and display adjustable in 1° increments with a range of 
80°-140°F. Display shall be capable of displaying setpoint 
temperature in Celsius or Fahrenheit temperature scales. Unit shall 
utilize a ow meter with a 0.3 gpm activation point and manage 
powerbased on actual ow rate and inlet temperature. Values 
should be processed 60 times per second.Unit shall be WQA 
certied lead free, certied to UL499 and CSA22.2. 
DESCRIPTION FEATURES
ROUGHING IN DIMENSIONS (SHOWN IN INCHES)
 MODEL NUMBER
kW
AMPS
RECOMMENDED
BREAKER
SIZE VOLTAGE
RECOMMENDED
WIRE SIZE (CU)
MIN.
FLOW
(GPM)
MAX.
FLOW
(GPM) HEIGHT WIDTH DEPTH
WATER
CONN.
SHIP
WEIGHT
(LBS.)
120V 1 HEATING CHAMBER
RMTEX-04 3.5 29A (1x30)A 120 10 AWG 0.3 4.8 5-7/8 10-7/8 2-3/4 1/2 NPT 4.5
240V* 1 HEATING CHAMBER
RMTEX-06 5.5 29A (1x30)A 220 10 AWG 0.3 4.8 5-7/8 10-7/8 2-3/4 1/2 NPT 4.5
RMTEX-08 8.0 33A (1x40)A 240 8 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 7
 RMTEX-08 (derated 208V performance)* 5.8 28A (1x40)A 208 8 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 7
RMTEX-11 11.0 46A (1x50)A 240 6 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 8.5
 RMTEX-11 (derated 208V performance)* 8.2 29A (1x50)A 208 6 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 8.5
RMTEX-13 13.0 54A (1x60)A 240 6 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 8.5
 RMTEX-13 (derated 208V performance)* 10.1 49A (1x60)A 208 6 AWG 0.3 4.8 12-5/8 8-1/4 3-5/8 1/2 CF 8.5
240V* 2 HEATING CHAMBERS
RMTEX-18 18.0 75A (2x40)A 240 8 AWG 0.3 7.0 18-1/4 14-1/2 3-1/2 3/4 NPT 14.78
 RMTEX-18 (derated 208V performance)* 13.3 64A (2x40)A 208 8 AWG 0.3 7.0 18-1/4 14-1/2 3-1/2 3/4 NPT 14.78
240V* 3 HEATING CHAMBERS
RMTEX-24 24.0 100A (3x40)A 240 8 AWG 0.3 7.0 18-1/4 17-5/8 3-1/2 3/4 NPT 17.8
 RMTEX-24 (derated 208V performance)* 17.5 84A (3x40)A 208 8 AWG 0.3 7.0 18-1/4 17-5/8 3-1/2 3/4 NPT 17.8
RMTEX-27 27.0 112A (3x40)A 240 8 AWG 0.3 7.0 18-1/4 17-5/8 3-1/2 3/4 NPT 17.8
 RMTEX-27 (derated 208V performance)* 20.0 96A (3x40)A 208 8 AWG 0.3 7.0 18-1/4 17-5/8 3-1/2 3/4 NPT 17.8
240V* 4 HEATING CHAMBERS
RMTEX-36 36.0 150A (4x40)A 240 8 AWG 0.3 8.0 18-1/4 21-5/8 3-1/2 3/4 NPT 22.7
 RMTEX-36 (derated 208V performance)* 26.6 127A (4x40)A 208 8 AWG 0.3 8.0 18-1/4 21-5/8 3-1/2 3/4 NPT 22.7


