fz300Hz questions

It’s been running fine since I bought it on the forum in 2017/8 and had a new battery fitted Jan 19 and I thought it was a faulty battery as it seemed to stall on the sweep for few seconds then continue as normal.
It then got slower and slower. Took at back under warranty for a battery swap but was told it was not the battery as it was still full of charge (tested) so it sounds like the central wheel is dirty and the watch needs a service and clean or the teeth are gone and part needs replacing.

Just sent my Certina Certronic off to fellow UK member keitht for a service. Comes highly recommended on all forums. You could see if he's taking on work.

@keitht posts infrequently but lurks regularly, so you may be able to send him a PM.

What's the manufacturer of the new battery?

The battery fitted in Jan 19 was a renta I think.

Renata are fine. But Energizer are not suitable for the f300. They tend to short circuit due to their shape. Renata and Varta have a slightly domed negative pole, Energizers are more flat.

So when I picked the watch back up they had not tightened the back so I had access.
Fast forward some spare time after 2 weeks of pandemonium I found by chance an unopened rental battery so I thought I would swap them over as I had my work tool bag with me due to ongoing situation.
What do you know, battery swap done and watch is running perfect.
I can’t tell you how annoyed I am at the 2 bit company I had the original battery change done by at £29-95 which was TTP but not having the tool to open the back and a 2 year guarantee I swallowed the pill.
But to go back less than 2 years later to be told the battery was fine and not their problem!! After having it 2 days!
Awful just awful and when this is all over I shall be visiting for a refund.
Just as well really as Mr electric is away for a few months if surgery had been required on my piece.

Regards
Jon