Does External Control Adversely Affect Electronic Heaters?

[ingchr1]

Is it good for a heater with an electronic thermostat to be controlled by an external controller? Does it lead to heater failures?

What affect does the constant on/off cycles have on the heater? Each time input power is cycled the heater goes through some type of initialization cycle. The heaters are designed to cycle their output, not have to have their input cycled. The tighter the control band applied, the more often the heater gets cycled.

Are external controllers inducing switching transients (voltage spikes, waveform distortion) on the heater each time the external controllers relay turns on or off? If so, what affect do these repeated transients have on the heater? Are switching transients something that controller manufactures have tested for as it’s something that can affect any device getting constantly cycled by the controller, not just heaters. It would be great if someone on the forum has access to a transient event recorder that can maybe get some waveform captures of different controller outlets cycling on and off.

I have started a separate thread to collect information on failures of heaters with electronic thermostats just to see if any insight can be gained. [URL="https://www.reef2reef.com/threads/electronic-heater-failure-database.570011/"]Electronic Heater Failure Database Thread[/URL]

 

[Lasse]

Personally – I do not trust heaters with inbuild control – my experiences say – it is not a question if it will fail – the question is when! I prefer titan heaters and an external temperature control. A titan heater will work as an ground probe too – because it is grounded.

But the "following up" thread is a great idea


Sincerely Lasse

 

[laverda]

In my experience heaters with electronic controllers are the worst of the lot. I will never use one again! No mater what heater your using it is going to be harder on it ant what ever your using to control if it is cycling frequently. There is no benefit to controlling it to 1 or 2 tents or even half a degree. It just is not needed. Both fish and corals can deal with 3-4 degree temp swing through a day. If you have ever been snorkeling you will feel much larger temp variations in just a few seconds.

 

[ingchr1]

Where I'm using electronic heaters, I'm using the heaters internal thermostat as the control with my external controller as the backup. I have my 40G main tank setup this way.

Where I'm using a more traditional heater, I'm using an external controller as the control with the heaters internal thermostat as the backup. I have a 15G tank with two 50W Eheim's controlled by a Cobalt Neo-Stat. I'm concerned with this as I see the Eheim's constantly cycling. Also, if the controller malfunctions in the on position how do I know that the internal heater thermostats are going to turn off at a reasonable temperature? You never get to see them operate, since the external controller is doing all the controlling. Unless you are periodically pulling the heaters to test them. At least in this setup I have two heaters, so hopefully both don't have failed thermostats.

In general external controllers are more reliable than heater thermostats. If you are relying on the heater's thermostat as the backup, do you really know or trust that that heaters thermostat is actually going to work when you need it most?

Personally – I do not trust heaters with inbuild control – my experiences say – it is not a question if it will fail – the question is when! I prefer titan heaters and an external temperature control. A titan heater will work as an ground probe too – because it is grounded.

But the "following up" thread is a great idea


Sincerely Lasse

For my future heater purchases I may look into just using titanium heaters. But I'm not sure they are available in the lower wattages that I need (150W).

Are there many, if any, documented catastrophic failures of this type heater? I find this type of failure to be the most concerning.

@Lasse I also like how you have your Profilux setup for heater control.

 

[HuduVudu]

I have been using Apex for quite some time now and am just now switching to GHL. My house is very old and for a time heating it in the winter was quite difficult. I have a 20g breeder and the cold has been way to much for most of the heaters that I have put on the tank. The only heater that seems able to keep up with this is 150w heater. I am using a Cobalt NeoTherm. Needless to say if this heater sticks on (which it eventually will) it will very quickly nuke my tank. I have had heaters do this and I won't have it again. Five or so years ago when I was dealing with this I looked at heater controls as a back up to turn the socket off. The Ranko was the first possibility that I considered. It was good, but then I saw that Apex could do the job also and it wasn't more expensive if I got the Apex Jr. I got the Jr. This gave me the power to turn off the socket and also warn me if the heater had failed and the temp was too low. Because of the extreme difference in my tank and the room during the winter either situation would be catastrophic. I had extra heaters on hand for a temp drop situation and the Apex would stop the over heat situation. This has been working every since.

Some things that I have seen. Apex temp probes (as all probes) can and will go bad. This is the same issue that happens with the heaters themselves. I have since bought an infared thermometer for sanity/reference checks. I plan on trying to find a good bulb thermometer too, just because you can never be too sure. I like that during the summer months the heater is completely off. For me this seems to extend the life of the heater and gives me peace of mind that the heater isn't part of the equation.

I am not against using the controller to control the heater, but the question becomes how do you achieve some sort of redundancy in this situation? I really think redundancy is the key to not frying your tank.

 

[laverda]

To use the controller to control the temp set you heater so it shuts off a degree hotter that you want your tank to be. The set the controller for what you want. You controller may already be controlling it more that you realize. Most aquarium heater are not very consistent about when the shut off. I have had them very by 2- 3 degrees one time to the next. The more a heater cycles the worse it gets as the switch points arch and stick together.

You might consider insulating your tank in the winter. This can really help with heat losses. I have 2 sides of a tank in my garage covered with thick foam insulation and it made a big difference.

 

[HuduVudu]

The more a heater cycles the worse it gets as the switch points arch and stick together.

I think that this is pretty obvious.

To use the controller to control the temp set you heater so it shuts off a degree hotter that you want your tank to be. The set the controller for what you want. You controller may already be controlling it more that you realize. Most aquarium heater are not very consistent about when the shut off. I have had them very by 2- 3 degrees one time to the next. The more a heater cycles the worse it gets as the switch points arch and stick together.

You might consider insulating your tank in the winter. This can really help with heat losses. I have 2 sides of a tank in my garage covered with thick foam insulation and it made a big difference.

I am not sure how any of this provides an answer to having the controller provide redundancy, when it is controlling the heater.

Also I am really not interested in turning a heater on and off in short intervals that is made to do that work itself. This seems like a very large recipe for disaster. If I wanted to do that I would by the no controller heater and use the controller to switch. Which leads once again to the problem of redundancy.

GHL provides better ways of dealing with heater control through pulsing, but Apex not so much. Honestly if there was a solid way of dealing with redundancy I would ditch the heater with control and buy the BRS titanium heater without the controller and control that way.

Why would I insulate a tank that sits in my living room that is meant to be a display, especially when the solution that I currently have has been working for 5 years? I didn't ask for a solution for the temperature of my house I asked for a solution to redundancy on controllers.

 

[Lasse]

With the GHL family you can with help of extension cards add an extra physical temperature probe if you want redundancy. You can use this as an extra alarm probe or have two smaller titanium heathers - one used as base and one that chimb in if it is needed. (you can do this with help of virtual probes too but if you use that - you miss the redundancy.

However - I have run many GHL systems and with the old PT-1000 probes - never have had any problem with them. The new digital probes (only option for P4) have been out for some years and the only problem I have had with them is together with expansion box 2 - where the digital signal just disappear now and then (this problem is solved in the next firmware). But when this happen - you get a direct alarm. It means that if they broke - you get an alarm according a broken probe. But - one very important things with external probes and heaters is that they need to be in the same place and/or compartment - otherwise it could be fatal.

Sincerely Lasse

 

[HuduVudu]

It means that if they broke - you get an alarm according a broken probe.

What is the alarm based on? Is it that the ProFlux recognizes that there is no signal and then alarms?

But - one very important things with external probes and heaters is that they need to be in the same place and/or compartment - otherwise it could be fatal.

Why is this needed? On my GHL set up, I have the heater in the sump in the middle compartment and the probe that runs it in the chamber that flows into it and the ProFlux probe in the chamber with the heater. I am ProFlux 4e.

I am really new to GHL and I am still trying to wrap my head around the way things are done, so that I can expand the possibilities of what I can do with my ProFlux. As stated earlier if I can do away with these garbage internal heater controllers I will. I just unwilling to give up redundancy to do so.

P.S. I have a stand alone doser and I think I am going to move it over to my new system and slave it to my ProFlux. This should give me the extra temp probe. It is good to know also that I can add an expansion card.

 

[Lasse]

Why is this needed? On my GHL set up, I have the heater in the sump in the middle compartment and the probe that runs it in the chamber that flows into it and the ProFlux probe in the chamber with the heater. I am ProFlux 4e.

Whats happens if the flow stops between the chambers? the profilux will stopp to regulate but the external will not. Cold house - temp in the first chamber going down - heater going on in the second chamber - no waterflow between them. I know people thats get boiling water in that type of configurations

P.S. I have a stand alone doser and I think I am going to move it over to my new system and slave it to my ProFlux. This should give me the extra temp probe. It is good to know also that I can add an expansion card.

Sorry to say - if you make the standalone into a slave - you miss the temperature function - it will not work in slave mode.

Sincerely Lasse

 

[Lasse]

What is the alarm based on? Is it that the ProFlux recognizes that there is no signal and then alarms?

When probes are out of range - you get a system alarm that is not connected with the alarm you by yourself can configure. If you activate a controller without connecting any probe - you will get an alarm too - the probe is out of range

Sincerely Lasse

 

[Spieg]

Where I'm using electronic heaters, I'm using the heaters internal thermostat as the control with my external controller as the backup.

This is what I do as well. Let the inexpensive/disposable heater take the wear and tear rather than an expensive controller power bar.

 

[Lasse]

My ideas is total opposite. Let the power bar take the wear and tear - they are build for that (at least GHL:s power bars - others I have no experiences of)

Here you can see my temperature curve the last month - between 24.9 to 25 degree C

I get this very stable curve because I use the pulse function. But the puls funktion gives an on/off cycle very often and are one for rather short time - my average is around 80 seconds (1.3 minutes) Below you see my last 24 hours - every staple is one on/off cycle

Since april this year - it have been around 34 000 on/off cycles with an average on time of 90 sec. I have run this configuration for around 2 years now.

Sincerely Lasse

 

[laverda]

I think that this is pretty obvious.


I am not sure how any of this provides an answer to having the controller provide redundancy, when it is controlling the heater.

Also I am really not interested in turning a heater on and off in short intervals that is made to do that work itself. This seems like a very large recipe for disaster. If I wanted to do that I would by the no controller heater and use the controller to switch. Which leads once again to the problem of redundancy.

GHL provides better ways of dealing with heater control through pulsing, but Apex not so much. Honestly if there was a solid way of dealing with redundancy I would ditch the heater with control and buy the BRS titanium heater without the controller and control that way.

Why would I insulate a tank that sits in my living room that is meant to be a display, especially when the solution that I currently have has been working for 5 years? I didn't ask for a solution for the temperature of my house I asked for a solution to redundancy on controllers.

As far as the heater is concerned the contacts would not be opening and closing on the heater. They would remain closed until the heater reaches is set point which it should not since the controller should cut it off before that.

 

[Pistondog]

Where I'm using electronic heaters, I'm using the heaters internal thermostat as the control with my external controller as the backup. I have my 40G main tank setup this way.

Where I'm using a more traditional heater, I'm using an external controller as the control with the heaters internal thermostat as the backup. I have a 15G tank with two 50W Eheim's controlled by a Cobalt Neo-Stat. I'm concerned with this as I see the Eheim's constantly cycling. Also, if the controller malfunctions in the on position how do I know that the internal heater thermostats are going to turn off at a reasonable temperature? You never get to see them operate, since the external controller is doing all the controlling. Unless you are periodically pulling the heaters to test them. At least in this setup I have two heaters, so hopefully both don't have failed thermostats.

In general external controllers are more reliable than heater thermostats. If you are relying on the heater's thermostat as the backup, do you really know or trust that that heaters thermostat is actually going to work when you need it most?


For my future heater purchases I may look into just using titanium heaters. But I'm not sure they are available in the lower wattages that I need (150W).

Are there many, if any, documented catastrophic failures of this type heater? I find this type of failure to be the most concerning.

@Lasse I also like how you have your Profilux setup for heater control.

The jaegers are bi metallic switches, not really affected by power cycles.

 

[HuduVudu]

The jaegers are bi metallic switches, not really affected by power cycles.

Not so worried about the switches as all of the electronics connected to the switches. Electronic equipement that is turned on and off very quickly that isn't designed for it very quickly become paper weights.

 

[ingchr1]

This is what I do as well. Let the inexpensive/disposable heater take the wear and tear rather than an expensive controller power bar.

The reason I did this was to not cycle the heater electronics, not for wear and tear on the Powerbar.

I have since switched to Eheim Jager heaters where I let the Powerbar do the cycling.

I also have GHL and not really concerned with it wearing out prematurely.

...Why is this needed? On my GHL set up, I have the heater in the sump in the middle compartment and the probe that runs it in the chamber that flows into it and the ProFlux probe in the chamber with the heater. I am ProFlux 4e...

Whats happens if the flow stops between the chambers? the profilux will stopp to regulate but the external will not. Cold house - temp in the first chamber going down - heater going on in the second chamber - no waterflow between them. I know people thats get boiling water in that type of configurations ...

One thing I did on my primary heater was to set it up so it turns off on low temperature. I can't see a reason for having an actual low temperature other than no flow or the probe gets pulled out the water. My secondary heater is lower wattage and does not have this logic applied to it. It would just rely on it's internal thermostat to shut off if too hot, but with the low wattage it's not going to go too high and will still give me heat to the tank.

I have an AIO and my heaters are in the return chamber and temperature sensor in the chamber before. My heaters should also turn off via their internal thermostat if too hot.

Here is how I did the logic:

Temperature 2 is a virtual probe where if it alarms the heater turns off. I set a virtual probe to get the temperature I want the heater to turn off, currently set at ~76F.

 

[HuduVudu]

Sorry to say - if you make the standalone into a slave - you miss the temperature function - it will not work in slave mode.

Ok this sux.
Thank you for letting me know of this "feature" (sic).

Since april this year - it have been around 34 000 on/off cycles with an average on time of 90 sec. I have run this configuration for around 2 years now.

This is impressive. I am feeling even better about my move to GHL.

@Lasse I see your thinking now. I am not sure that I agree with you because of cost factors, but understand and appreciate where you are coming from.

I appreciate you jumping in and explaining.

 

[ingchr1]

The jaegers are bi metallic switches, not really affected by power cycles.

Not sure what I was trying to get at with that part of the post, maybe not worded quite right.

Agree, not really too concerned with bi-metallic cycling compared to turning an electronic heater on and off by an external controller.

 

[Pistondog]

Not so worried about the switches as all of the electronics connected to the switches. Electronic equipement that is turned on and off very quickly that isn't designed for it very quickly become paper weights.

Sorry, wasn't clear.
Ehiem uses bi metallic thermal switches, no electronics to suffer power cycles.
As temperature increases, different coefficients of expansion in different metals cause the current carrying contacts to separate.
When they cool enough the contacts close.
Same idea as thermal safety in hot tubs.