Newly installed immersion heater suddenly stopped working after a week. What could be the issue?

[VirtuosicVirtuoso]

I've recently replaced an immersion heater for a direct cylinder, for 2.75-3kW. The new one seemed to be working a week before I got a callback. I checked the resistance of the immersion heater, and it read 19ohms, and the voltage on the live and neutral read 230V, but there was no humming or vibration from the heater. I tried fiddling around with the wiring, and turning it on and off from the thermostat and the switch, and that Brough the vibration back, but after fiddling around again, it seemed to stop. I don't think loose wiring is the issue, so I'm not sure what the issue could be. Any advice would be appreciated. Thank you.

New immersion heater and thermostat: Tesla All Incoloy Immersion Heater & Plug In Stat 14 inch - 1 1 3/4" Boss

 

[John.g]

Is this a bottom (horizontally) mounted immersion?, was the thermostat renewed?, did you check the old element resistance?

 

[VirtuosicVirtuoso]

Is this a bottom (horizontally) mounted immersion?, was the thermostat renewed?, did you check the old element resistance?

Yes, it's a bottom mounted one, and the new immersion heater came with a thermostat. The old immersion heater's resistance was reading 30ohms, and the element had corroded, which is why I had replaced it. The new one's resistance is 19ohms

 

[snowhead]

Is the plug-in stat pushed hard onto the element terminals?
Does the overtemp stat need resetting?
Have you checked continuity through the stat, for both Live and Neutral?
Check the connections in the Fused connection unit / switched fused spur, a poor connection may show 240v with a tester but break down with the load of the heater on it, same applies to the FCU / Fused spur itself, the switch / fuse holder may be failing.

 

[VirtuosicVirtuoso]

Is the plug-in stat pushed hard onto the element terminals?
Does the overtemp stat need resetting?
Have you checked continuity through the stat, for both Live and Neutral?
Check the connections in the Fused connection unit / switched fused spur, a poor connection may show 240v with a tester but break down with the load of the heater on it, same applies to the FCU / Fused spur itself, the switch / fuse holder may be failing.

I pushed the plug-in stat as far as possible.
No reset was needed
Does a resistance of 19ohms not work as a show of continuity?
There was previously a Fused spur with a 13a fuse I it, which was working from before. To make sure it wasn't the issue, I replaced it with a 20a fuse switch, and I'm certain I made sure the wires were firmly in place (but I'm no electrician).
The landlord brought in an electrician that mentioned that the circuits could be on a 16a breaker, so I'm not sure if that could be a concern?
Other than that, I'm not sure where I've gone wrong, or maybe I need to go over everything step by step to make sure I didn't make a mistake.

 

[Rtplumb]

I pushed the plug-in stat as far as possible.
No reset was needed
Does a resistance of 19ohms not work as a show of continuity?
There was previously a Fused spur with a 13a fuse I it, which was working from before. To make sure it wasn't the issue, I replaced it with a 20a fuse switch, and I'm certain I made sure the wires were firmly in place (but I'm no electrician).
The landlord brought in an electrician that mentioned that the circuits could be on a 16a breaker, so I'm not sure if that could be a concern?
Other than that, I'm not sure where I've gone wrong, or maybe I need to go over everything step by step to make sure I didn't make a mistake.

Just a thought but did you check the fuse box for a tripped switch?