Your tankless water heater is a relatively new type of heater and there is a learning curve in using your new heater. We ask that you read this to diagnose any issues you might encounter. We expect you will have many, energy efficient, money saving years with your new Stiebel Eltron Tankless Water Heater.

Disclaimer: Tankless Hot Water, a division of LLC, assumes no responsibility for impoperly installed heaters, nor does it assume any responsibility for the end user troubleshooting or self diagnosing water heater related issues. If you are unable or not familiar with any of the issues discussed below, do not attempt self diagnostics. Call a qualified service mechanic.

1. I have no hot water

Do you have hot water, but just not as hot as it has been? Or do you literally have no, as in zero, hot water?
Is your LED light on? Does the red activation light come on as water is flowing thru the unit?

The first thing to do here is to verify that the LED light is on, meaning you have power to the unit. If the LED light is not on, check the circuit breaker to make sure it is not tripped. Keep in mind, with a tripped breaker, when it trips it goes to a neutral position, not on and not off, dead but not off. So, put the breaker in a full off position to reset, then turn it on. Do you now have a LED light, if so, try calling for hot water.

If you have power to the unit, the LED light is on, but the red activation light don’t come on when calling for hot water, you might have a dead water heater. What is suggested here is to verify that you have proper voltage to the heater. If you have the voltage, have good connections, then you might have a faulty heater.

If you have power to the unit, the LED light is on, and the activation light comes on when calling for hot water, yet you have no hot water, then it sounds like you have a dead water heater.

If the water is just not as hot as it was earlier, consider whether the groundwater temperature has dropped. Usually this is only a concern to people experiencing their first winter with a tankless water heater. Sometimes, in colder weather, mainly November thru March, the groundwater temperature, meaning the incoming water to the heater, has cooled 5 to 15 degrees, resulting in a lower output temperature. The answer here is to not max out the capacity of the heater. So, in cooler months, do not push to capacity.  Once the ground warms up, all will return to normal. We suggest people set the temperature to 115-120 during the hot months, and then when it cools a bit, you can increase the temperature to offset the cooler groundwater.

2. The heater is making a clicking noise

There is a flow switch that clicks on and off when water starts and stops flowing thru the heater. This is normal and few, as in very few, people ever notice it. Those that notice it, usually have the heater located in the house somewhere, not in the garage where the bulk of the heaters are located.

3. My lights flicker when the water heater is heating water

This can sometimes happen, though rarely. This is usually in a house that has a small or old electric panel. Sometimes this is unavoidable. Ever notice how sometimes when your AC kicks in, the lights might flicker for just a spit second. This is because it take the most amps to get the AC compressor to start turning, once it is turning, the amps needed to turn it drop considerably. Not with a tankless. When it fires, it goes to 90 to 100% of capacity and can sometimes stay there, depending on the temperature and the amount of hot water you are calling for. An important thing here is to make sure you have sufficient amp capacity in your electrical panel. We recommend a minimum of 100 AMP panel for a T-12 up to a 300 AMP panel for a T-36. Exceptions to this might be a gas home, a home without cental air, or without multiple 220 volt appliances. Another thing to keep in mind, all your 220 Volt breakers should be nearest the main lugs feeding your electrical panel, and evenly balanced.

There is water dripping from inside the heater

This is rare, but it does happen. We glady replace leaky water heaters. Just verify that the actual water heater is leaking, not a valve, or fitting, or the AC above, and call us.

5. My heater comes on when the toilet is flushed or something calls for cold water in the house

It took us a long time to figure this one out. This is very rare, yet once or twice a year we hear about this. What is happening here is that cold water pressure is holding the flow switch in place preventing the unit from activating. When something calls for cold water in your home, such as a toilet, faucet or washer, it relieves some of the pressure and the red lights might turn on for a nanosecond.  Rest assured that the heater is not coming on, it is just a little confused about the water pressure reduction.

6. Sometimes I get a blast of cooler water, then it goes to hot again

Couple of things here. If you are downstream using hot water, and somebody between you and the water heater calls for hot water, they will get the hot water first till the heater figures out it needs to provide more hot water. It then does, and you once again have hotter water. Also keep in mind it takes a .4GPM flow rate to a .9 GPM flow rate, depending on the model, to activate the heater. This is part of the learning curve in adjusting to a tankless water heater.

7. I can’t seem to fill my bathtub with hot enough hot water

Once again, part of the learning curve here. Most people when they fill a tub, open the hot wide open knowing they will soon run out of hot water. This is because, with a standard type of water heater, when you take 10 gallons of hot water out of it, you have then replaced that with 10 gallons of cold water, diluting the reservoir. 20 gallons of hot out, 20 gallons of cold in, simple as that. However, since there is no reservoir to dilute with a tankless water heater, you need to slow the flow of hot water allowing the tankless unit to keep up with demand. Please note that if you open the hot water valve all the way, you might be pulling 4, 5,  6 gallons or more a minute thru it. The tankless will try, but will be unable to keep up. The answer is to open the cold half way, add enough hot to make it almost too hot, and fill up the tub. You will be able to fill that tub, the next tub, and the next tub.

8. My washing machine does not put out as much hot water

Kind of like the battub thing. Too much demand. The answer is to close both the hot and cold valves completely. Then open or adjust both valves until you get the desired mix. This might take a minute or two longer to fill the washer, but it will be nice and hot when needed.

9. But what about my dishwasher, it needs 140 degree water to sanitize the dishes

A big mistake people make here. Some people mistakenly set their water heater at 140 degrees, which by the way voids the water heater warranty and is terrilbly expensive to maintain 40 or 50 gallons, or more, or 140 degree water 24 hours a day whether they are home or not.  The first thing you are going to do with 140 degree water is add a lot of cold water to it. All water heaters have a sticker on it that says water over 125 degrees will burn you. If you have children or grandchildren, I am sure you have noticed that. Take a look at your heater, find the sticker. There is no need to have your heater set that high, it is foolish, dangerous and expensive. Unless you have a $39 dishwasher, it has a preheater in it to take the water to 140 degrees. Let the dishwasher do the job. Most people bathe in about 100 to 105 degree water.

10. What about service and service calls?

If we installed, we offer these options:

A Within 30 days of installation, there is no charge for a service call.
B After 30 days, there is a county specific service call.

If you installed, or had installed, we offer these options:

A We can, at our option, provide a county specific service call.
B We can ship you another heater, and you have it reinstalled.
C You can stop by the office and exchange heaters at no charge.
What about shipping costs and reinstallation costs?

Shipping costs incurred for any reason, and/or reinstallation costs, are not reimburseable to the consumer.

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