Eheim Jager and Thermocontrol E heaters mounting

[Bucio]

So im one to read through the instruction booklet, shocking! I know, but i found that in the book it says to mount them vertically only. Yet i have seen many YouTubers recommend to put it horizontally. My question is does putting it horizontally damage it in the long term? Has anyone had these heaters in the horizontal position for years on end? 

[Lyon Aquascapes]

Hi Bucio,

I had a classic Eheim Jager heater go bad that was positioned horizontally. I don't know if the position was connected to it going bad but I think it is best to keep them vertical. Otherwise I have never had a Eheim heater break on me. But on a positive note they replaced the heater for free as it was still under warranty.

Will

[Paul]

@BucioI have one diagonally in a 10 gallon. It’s working fine.

Edited December 18, 2020 by Paul

[3vi1p3nguin]

I had one horizontal for close to a year before I re-scaped the tank, and it didn't fail for that long at least. I did have it directly under a downward pointing spray-bar though.

[Frost]

I have a 200 watt Jager diagonally in a tank, and it's been working fine for almost a year now, it's so tall I don't think it could even fit vertically

I've heard they're good heaters but I have to say they seem oversized compared to other brands