Heater Problem

[Maho.B]

Hello, my system came with a heater that is controlled by a unit called jbj lighting digital heater controller. I was away a couple of days, just got back and doing the normal "checking in" on things and noticed the digital thermostat says "HI" and when I try to change the temp setting it remains in this "HI" reading. I grabbed a thermapen (a digital food thermometer) and used it to test the water and it read 79. My heater is normally set at 78. Does anyone know what would cause the "HI" reading on the display and how to fix it? I am concerned I will wake up to hot water and a dead reef tank! Thanks in advance.

 

[VintageReefer]

It means the tank is over the set point. It’s saying the temp is high and likely is turning off the heater until the temp goes back down

If the controller is functioning it will turn on the heater when the tank gets too cool, and turn off the heater if it gets too hot. It needs to get a degree or two over the set point to register “hi” or “high” but then it should kill the heater until temp is back down to low set point

 

[lapin]

 

[VintageReefer]

There should be an indicator if the heater is on. Most likely a led. If the controller says hi and the heater is off, it shouldn’t get any hotter or cook your tank

 

[VintageReefer]

Oh. It’s not Hi. It’s H1

Good call checking the units manual

In this case it’s thinking the tank is over 99. If you trust the therma pen and the tank feels normal, then your controller probe is bad.

Take it out of the water, clean it, and set it on a counter. Unplug the heater also.

Wait 10 - 15 min and see if it reads a temp close to what your house temp is set to

 

[VintageReefer]

Just found this review, same issue

Suggested replacement if you want:

https://a.co/d/9WgItVe

I’ve run these on two tanks for 8 years and 10 years, flawless performance

 

[Maho.B]

Thanks for the replies everyone, very helpful! I woke up this morning and the thermapen said 77 (it was 79 when I went to bed) and the controller still reads H1 and the LED indication the heater is running isn't illuminated so it's definitely malfunctioning, it's set to 78. I'll take the advice and remove/clean/test it to see if that works, if not does anyone like (trust) the heater they have? I'll have to get one today if this one is shot. By the way lapin thanks for finding the section in the manual about H1 not HI...my heater came with my set up so I didn't have one. Thanks!