No hot water. Display reads ER3. - Water Heaters

Simply means hot water heater called for heat for 1 hour and never rose in temperature or reach stepping, unit automatically goes into lockout. I would reset power

Had this happen to me before, if you have hot water from the boiler going in and out of the boiler mate and the temps are not rising within the hot water means more than likely you may need to remove exchanger and clean sediment off element, basically sediment creates a blanket over the heat source causing poor thermal conductivity. Things to check before removing heat exchanger

- outlet temp of boiler water to aquamate -inlet temp of boiler water to aqua mate= 20-30'F if low then bad thermal transfer or poor water movement
-make sure sensor is reading properly
- get boiler temp higher to speed up thermal gain in water heater

is it an electric or gas or oil fired. Er3 means it is not getting up to temperature within the required time. Electrical - element bad. for oil or gas, no ignition or fuel supply.

It tells you that your water heater called for heat for more than an hr and never got hot enough to meet the demand.
CAUSES

-bad sensors
-no hot water from boiler
-bad thermal transfer
-low delta T across water heater

It tells you that your water heater called for heat for more than an hr and never got hot enough to meet the demand.
CAUSES

-bad sensors
-no hot water from boiler
-bad thermal transfer
-low delta T across water heater

It tells you that your water heater called for heat for more than an hr and never got hot enough to meet the demand.
CAUSES

-bad sensors
-no hot water from boiler
-bad thermal transfer
-low delta T across water heater

It tells you that your water heater called for heat for more than an hr and never got hot enough to meet the demand. multiple scenarios can cause this
CAUSES

-bad sensors
-no hot water from boiler
-bad thermal transfer
-low delta T across water heater

It tells you that your water heater called for heat for more than an hr and never got hot enough to meet the demand.
CAUSES
-bad sensors
-no hot water from boiler
-bad thermal transfer
-low delta T across water heater

Er3 means that the water is being heated for more than 1 hour without reaching the set temperature.
Need new aquastat.

The smart control was only reading 140 it never went up or down from that number and now it has an ER3 code seem the circulator just runs and runs