Question about Amtrol ST-12-C THERM-X-TROL ASME Expansion Tank, 5 Gallon

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Water heater is beeping with er- 120 flashing

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If water heater is beeping E-2 it means that the water heater has gotten to high above water heater set point. Things to check

- there hot water being feed from boiler still
- is zone valve or pump isolated stopping flow of water to water heater
-check sensor readings

Posted on May 29, 2017


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Posted on Jan 02, 2017


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1 Answer

Richmond tankless water heater My system keeps flashing 29 and is beeping

A 29 error code indicates a neutralizer drainage failure. The neutralizer is designed to drain condensate away from the heater. If the neutralizer and/or drain becomes blocked up, the unit will flash the 29 error code to prevent the burner from being flooded.

Jan 01, 2018 | Water Water Heaters

1 Answer

Can I install a 19 gallon hot water tank to a 120 volt breaker?

Anon, It would only work if that was meant to be hooked up that way. Check the specifications in the manual or the plate on the heater itself. Check the attached links,instruction and guides, 1st link shows typical wire hook up on both 120 and 240 v. Good luck .
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
Basic 220 Volt water heater circuit
Common Mistakes in Hot Water Heater Installation Hot Water Heaters
How to Install 120 Volt 20 Gallon Electric Water Heater
electric hot water heater specification plate Google Search

May 22, 2016 | Water Water Heaters

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What does it mean when heater flashes Er2?

Your manual should have a troubleshooting section. Er would mean an error, and the 2 would indicate the problem area.. You could also call the manufacturer at a number usually on the nameplate. You may also Google the manufactures name/Er2 and see what comes up. Good luck. Try to find out soon so the error doesn't increase with time.

Nov 01, 2014 | Water Heaters

1 Answer

2 green flashes. hot water is blazing hot set at 120 degrees.have the energy smart unit model#ee2h50rd045v . what is wrong?

2 green flashes is 'High Water Temp.'

Typical energy smart manual:

3 flashes is Temperature Sensor failure.
4 flashes is Upper element
5 flashes is Lower element

Troubleshoot section says:
1) Make sure access doors and insulation are installed.
2) Check elements for resistance of 5-25 ohms (if element has a short in center of element, it might not trip breaker)
3) replace element and reset control system.
Buy ordinary 4500 Watt element from hardware store.

4) I also suspect the self-diagnostic control box.
Manual says: Repair parts may be ordered through your plumber,
local distributor, home improvement center, or by calling
You need serial number, product number and model number from label on side of tank.

Jan 11, 2011 | Whirlpool Water Heaters

2 Answers

I have a bosch YS2433R 'Highflow' hot water system. It has a YPRM34XB controller. The controller constantly flashes the number '99'. My home has no hot water. How do I fix this error on the controller so...

Solution for a code 10 or 99 (for my own reference as much as anything!)
Hit change and the down arrow on the controller for 3 seconds.
Wait for the controller to beep and display 00 before using the down key to display 93.
Hit the On/Off button until 000 is displayed on the screen.
Press change and down simultaneously and the controller should revert to the pre set temperature. Hey presto! Hot water!!!

Nov 01, 2010 | Bosch & Tankless LP Hot Water Heater

1 Answer

Whirlpool Energy Smart Water heater - light is solid green then every now and then blink a couple of times then go solid again.What does this mean?

2 flashes = high water temperature (the water heater comes set at 120, and you can set it lower or higher)
3 flashes = sensor failure (temperature sensor similar to a thermostat on regular water heater)
4 flashes = upper element
5 flashes = lower element
Links below are for Whirlpool manuals

The water heater is working right now.
If the elements go out, they are available at any hardware store.
The temperature sensor is easily replaced and can be ordered from Whirlpool.
You might want an extra temperature sensor on-hand so repairs are not delayed.
Link below shows the product in detail.
Let the water heater do its job until it fails.

Oct 22, 2010 | Water Heaters

1 Answer

Beeping noise

E2 means hot water over shot, make sure to check boiler hot water system to make sure zone valve or control is staying closed when the call for boiler hot water to the water heater is isolated. Sometimes a zone valve will fail open or not close properly causing hot boiler water to constantly feed the water heater.

Dec 08, 2009 | Amtrol Water Heaters

1 Answer

This things beeping and flashing 12 everytime we

check the error codes on it by pressing the on off button for 2 seconds then while holding the on/off button press the up button this should display the last 9 error codes let me know what they are

Jul 28, 2009 | Rinnai Water Heaters

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