Super Hot EPJ-119-SC, Installation And Service Manual

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EPJ SERIES INDIRECT WATER HEATERS – Installation and Service Manual
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Water Adjustment Section 6
DANGER: Water Temperatures over 125°F (52°C) can cause severe burns instantly or death from scalds.
Feel water before bathing and showering. Homes that have small children, elderly and disabled persons
may wish to lower the water heater setting to 120°F (49°C) to prevent potential scalding. Below is a table
showing the approximate time it takes to have a scalding accident for different temperatures of hot water:
Water Temperature Length of Time to Cause Scalding
125ºF (52ºC) 1 1/2 to 2 minutes
130ºF (54ºC) about 30 seconds
135ºF (57ºC) about 10 seconds
140ºF (60ºC) less than 5 seconds
145ºF (63ºC) less than 3 seconds
150ºF (66ºC) about 1 ½ seconds
Maximum boiler water temperature is 210ºF.
A thermostatic mixing valve or tempering valve should be
installed on the domestic hot water supply and set to a
maximum of 120°F (49°C).
Valves for reducing point of use temperature by mixing cold
and hot water are available. Consult a licensed plumber or
local plumbing authority.
WARNING: Studies show that dangerous bacteria can form in domestic water distributions systems if a
minimum water temperature is not maintained. For example, legionella pneumophila , can form in hot water
maintained at 115°F (46°C) or lower. We recommend a domestic water temperature not lower than 122°F
(50°C) at faucets and a tank temperature not lower than 140°F (60°C) to limit the potential for
legionella
pneumophila growth. Contact your local health authority for more information.
6.1 CONTROL AQUASTAT
A control aquastat and thermowell must be installed in order to control the maximum temperature of the
tank. The upper limit of the aquastat’s adjustable range must not exceed 150°F.
First, install the well in the “SENSOR WELL” fitting, then insert the control aquastat into the well and secure
the set screw on the aquastat body or as per the manufacturer’s instructions. Thermal paste is
recommended but not required.
The aquastat will control the tank water temperature within a close tolerance to the aquastat temperature
setting, but unusual usage patterns may cause the outlet water temperature to rise significantly above the
aquastat setting. To control fluctuating temperature, a thermostatic mixing valve (tempering valve) must be
installed.
6.2 AQUASTAT TEMPERATURE

Use the aquastat to control the maximum water temperature in the tank.
 Household water usage patterns will affect water temperature at any faucet or shower. Always
check temperature at every point after adjusting aquastat.
 When hot water is used in repeated small quantities the upper layer of water in tank can be much
hotter than lower layers. When adjusting the aquastat, be sure the boiler operating limit control is
set a minimum of 20°F (11°C) higher than the aquastat setting. However, in no case should the
boiler operating limit control be set above 210°F (99°C).

Maximum tank temperature is 150°F.