Today I want to tell you a tale of misfortune, fear and anger. My U200 seemingly stopped unlocking the door properly and I almost locked out my wife.
I had a U200 with an Aqara Adjustable Cylinder (made specifically for the U200) mounted into a mortise lock. The cylinder is actually quite solid (and uses a dimple key), it looks like this:
The extensions are secured with small screws at the bottom and, if you don’t screw them firm enough, they could fall apart when you slam the door. But the cylinder is also secured with the standard screw, so it should be good.
Ok, without further ado
The early symptoms that something is wrong started two weeks ago. The U200 started struggling a bit with a second turn when unlocking the door.
But it didn’t stop or anything, it was still able to fully unlock the door. It just started being louder, like it needed more force.
I didn’t think much of it. It’s hotter (28+°C, 82+°F), the metal parts may have expanded (including the door), I haven’t charged the U200 once. Actually, I have, immediately after buying it - so after 6 months, I still have 40% left.
But batteries’ voltage drops when they are discharging. So 40% = lower voltage. And lower voltage means the motor may be struggling.
So my consensus was - seems normal.
Oh boy, was I wrong….
Day 1
4 days ago, when I was going out, the U200 REALLY struggled with the second turn. “I need to charge it at last” I thought to myself and went out.
The door auto-locked behind me, like it always does. I use a window and door sensor to automate locking the door, so it’s always locked.
An hour later, I went back home. Put my finger on the fingerprint scanner, the U200 made the first turn, then it almost jammed during the second turn, but I pulled the door hard to make the mechanism “jump” and help the U200. It unlocked. I went in and closed the door.
It didn’t fully lock this time - I got a push notification saying “Cylinder error”, and the U200 started playing an alarm.
I sighed, thinking it’s the infamous U200 problem of faulty grease/grinding gears. So I started repeatedly locking and unlocking the door (manually) to test the lock.
Of course, I opened the door first.
The lock jammed after the first turn. The bolt was stuck halfway out. I was not able to move it any way (or close the door, because the bolt was in the way).
“Oh well”, I thought sarcastically , “so I am the lucky user blessed with the gear problem”.
I unmounted the U200 and put it away. Then I tried to unlock the door by moving the driver bolt of the adjustable cylinder with my pliers.
The Aqara Adjustable Cylinder does not use a key on the inside - it has a bolt like this that is meant to be turned by the U200:
It was also stuck.
“What the… did the cylinder fall apart when I slammed the door yesterday?”
Yes, it’s my fault I slammed the door the day before. But it was accidental - as there was a draft that pulled the door.
I was finally able to unlock the door by using a flat screwdriver (it goes into the lock instead of the driver bolt) and a lot of force. And it was really a lot - thought either the cylinder, or the screwdriver, will break.
Actually I was really lucky that I didn’t lock out my wife. Say, the lock would jam like this when I locked the door a little earlier. She would not be able to unlock it herself, I would have to help by giving her instructions on the phone, but even then - she doesn’t have as much strength in her hands as I do, she wouldn’t be able to turn it.
Calling a locksmith who would be able to break in, and destroy the lock… and potentially a part of the door… phew, glad it didn’t happen.
I had to go back to work (I work remotely and sometimes we have to work in the afternoon or at night), so I ordered a new Yale cylinder on Amazon. It’s a non-adjustable 30/50 cylinder (so no extensions that could fall apart), so I thought - it would be better and less hassle to mount it, right?
Amazon had a next day delivery (and it was the only place with next day delivery when you order at 4PM/16:00) so I was able to mount it the next day.
And fortunately (or not, because cylinder problem is also a big problem) it wasn’t the U200.
Day 2
I unscrewed the shield with the door handle. It’s actually a single part and I wasn’t able to pull the lock while it was mounted.
When you unmount a cylinder, you have to put the old key in and turn it partially, and I was only able to put the key outside, as inside the cylinder only has the bolt. And the bolt is loose, it it can’t be used to pull the cylinder. So the only option is to put the key and push the lock from the outside.
But - the shield. The shield looks like this, and the key is wider than the crevice, so you are not able to pull the key through it:
Ok, handle disassembled, cylinder unmounted. Let’s check the cylinder one more time, did the screw come loose?
Nope. The extension is sturdy.
So maybe it’s something inside?
Nope. The cylinder now moves very smoothly, almost effortlessly.
Strange… but maybe it jams only when using the driver bolt from the Aqara Cylinder, so I tested one more thing.
I put the Yale cylinder in and started testing it. It locked and unlocked normally, so I put the shield and door handle… and it’s jammed. The lock stopped working again.
So what’s happening? I unmounted the shield. The lock is still stuck, unless I jiggle it while unlocking.
Then it came to me…
The mortise lock. It’s the mortise lock. That was the only explanation.
People living in Europe, you know mortise locks are used everywhere, right? And they are found in most shops like Obi, Castorama, Leroy Merlin, Bricoman (explanation for our friends from the US - those are our Home Depot, basically something like a DIY shop)
So it should be easy enough to buy a new one, right?
Just take some measurements of the bolt, distance from the door handle to the cylinder crevice and distance from the cylinder crevice to the edge of the door.
Measurements taken aaaand it’s not a common mortise lock. I’m not able to just buy it, I need to order it online or a retailer has to order it for me from the manufacturer.
Fortunately there was one shop that had a replacement lock available to buy right now. I called them and they said that yes, they have it in stock and can send it right away.
The delivery company picked the package the next day, so I received it 2 days after making the order.
Day 4
So today the mortise lock came. I mounted it, the cylinder, the U200. Everything works now perfectly, and locking and unlocking is much smoother now.
So it turns out sometimes it’s not the U200 that’s the problem, as many people think. I’ve seen a lot of reports on reddit about the U200 jamming.
Check your cylinders and locks before installing the U200! Or maybe just replace them before installing the U200, just to be sure.
Bonus: photo of the culprit
And a video of the problem
