20 Most Recent RTO American Heat Tankless Electric Water Heater Questions & Answers


I have an American Heat AHK1. The power went out and when it came back on the heater no longer turns on or even lights up. The digital display showing on/off and temp no longer lights up. Is there a

If you had a power surge at your home, and no more power seems to be going to the heater, you must make sure that none of your wires from the load center all the way to the heater are intact and all have been wired correctly and none are lose. If you must be very careful reading manufacturing dates as these dates are actually displayed backwards and the year is actually displayed as the month, you may in fact have an older heater, as sometime when these heaters are purchased by distributors they don't get to sell them until way after or they have had one in storage for a while when they decide to sell them. I have spoken to the guys at the factory and they are very informative, I don't see how they could not help you as I deal with them on a daily and we always try and help there customers, why don't you bring the heater in there service department is great it only takes 5 minutes to fix the heater. If you mail it in its only 24-72 hr turn around.
4/7/2014 4:03:15 PM • RTO American... • Answered on Apr 07, 2014

Error codes

Be the first to answer 1/27/2014 3:15:12 AM • RTO American... • Posted on Jan 27, 2014Be the first to answer

I have an American Heat adk-1. As of this morning

You need to get a real tankless water heater, I had one of this brand and what a waste of money, when you call the company they do not speak very good English and if you talk to Richard whom is supposedly the VP he is as dumb as a mule.
4/2/2013 3:25:41 AM • RTO American... • Answered on Apr 02, 2013

I have model AH21 Tankless Water Heater and it is not heating the water

try these steps - hope it helps
  • Selected temperature on your tankless water heater is too high. Select the lower temperature.
  • Inlet filter is dirty... clean it.
  • Make sure that there are no water path obstructions, including faucet aerators, shower heads...
  • Is the heater using the specified gas type?
  • Temperature sensors are loose... ensure that sensors are firmly mounted and are making contacts.
6/7/2012 3:38:41 AM • RTO American... • Answered on Jun 07, 2012

My American Heat ADK-1 is

The problem is usually the thermal saftey cutout switch....this can be manually reset, but if it continues to cutout then the thermostat is bad and needs to be replaced...

You can see all of the parts and where they are located by going here and checking out page 4

9/8/2011 10:54:56 AM • RTO American... • Answered on Sep 08, 2011

Tankless heater says standby and

You must to make sure that you have not used too much teflon tape, and also that the flow sensor is still inside the inlet pipe. For example these units some with a reed switch type flow mechanisim which when flow is detected it opens the door for the electricity to pass through the unit. so no Flow no power, or in your case there maybe something clogged, or your flow sensor is not inside the inlet pipe, also if this unit has been installed previously and had been working for sometime now, then check on the inside pipe behind the screen you will notice there is a small black or either white bullet style flow switch, if this flow switch is stuck on the inside of the unit, this is your problem, if not its a reed switch, you can call 1-888-818-4328 and ask for an ADK reed switch see picture attached
2/18/2011 8:42:39 PM • RTO American... • Answered on Feb 18, 2011

ADK-1 Super------------why is it that I have to

If you live in an area where you have hard water it can destroy pretty much any tankless water heater, but it seems that you may have another problem, I speak to them on a regular basis and everyone there seems to speak English and Spanish, its very important to make sure that this unit is installed by a liscensed person, whom will check your wire gauge, and breaker size, if you use 240v this unit can draw upto 66 amps, so its important to have an electrician size your heater for the correct voltage.
2/18/2011 8:36:17 PM • RTO American... • Answered on Feb 18, 2011

No hot water can't even take a shower

If there is only cold water coming out from the water heater, there is no doubt that your RTO water heater
is defective.
1. Shut the power supply going to your heater off.
2. You can check on it, by opening it up.
3. Trace the wires coming from the power supply.
Using a multitester, check the continuity of each
line. Set the tester to Ohms 1 x 10. Put the multi
tester probe to each end of the electrical line, one
line at a time. The pointer must point to zero.
Otherwise, it must be replaced.
4. Test the heater coil for continuity. One of the multi
tester probe must be placed at the common termi-
nal. Put the other probe to the other terminals. The
pointer must be at zero, otherwise, you can
replace the heater unit, since this is already
12/11/2010 9:35:16 PM • RTO American... • Answered on Dec 11, 2010

Wired yellow to green,blue to black,red to

OK Black is the PHASE... In USA, So that may actaually go to the RED, goes to the Black. The Green MUST be earth
So I guess that leaves RED as Neutral? Doesn't sound right, so I wonder if your wiring is right.
The breaker trips because there is a short circuit, OR the Phase is touching Earth.
It does sound logical though the way you have it wired, I would have thought that would have been correct...
Are you sure you don't actually have fault, within the unit?
You need to meter the Phase & Neutral, and see what's what. IF you DO have it OK, and I suspect you do, then there MUST be some other issue.
8/11/2010 8:01:19 PM • RTO American... • Answered on Aug 11, 2010

Hi, is not working, the machin is turn on but we

Possible causes and solutions:
  1. Safety Thermal Cut-Out Tripped, Reset.
  2. Not enough flow rate to activate unit, clean filter screen at unit, clean aerator at faucet.
I hope this has helped. Please rate the answer as to it's helpfulness. Good Luck and have a great weekend. Jeff
4/4/2010 4:48:05 AM • RTO American... • Answered on Apr 04, 2010
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