Replacement Central heating Programmer

[jbtaylor84]

Hi All

Would really appreciate some help on the following....

I currently have an old Glow-Worm Mastermind programmer (believe this is also known as a Landis & GYR RWB2). The timer function does not work any more (clock doesn't spin correctly), so i am looking to replace it. I have aquired a second hand British Gas UP1 (which i think is also known as an ACL Drayton LP1112?).

My question is - Is the BG UP1 a simple direct replacement for my old Glow-worm MM? Can i use the existing backplate and just plug the BG UP1 directly on without altering the wiring?

For what it's worth the wiring diagram on the back of each unit looks very similar, the only major difference is that teh BG UP1 states a 3Amp fuse must be used, but currerntly the GW has a 5Amp fuse.

Can anyone shed any light on this for me?

Thanks in advance.
Ben

 

[45yearsagasman]

Remove your existing programmer(2 screws underneath) and check the back plate connections.If it shows identical numbered connections in the same position then simply attach the new timer.Most systems are fused at 3 amp unless otherwise stated in boiler instructions.I'm sure that the backplates are the same.Don't forget power off when doing this.

 

[jbtaylor84]

Thanks for the speedy reply....

I took it off last night and it does show identical numbered connections i.e. N L 1 2 3 4.

What confused me is i have the backplate that was used on the second hand BG UP1 programmer as a referance and the wiring on that looks slightly different to the wiring on mine, i.e. mine has no wire into connection 1 but the BG UP1 does. Will this be becasue it was hooked up to a different boiler or does it mean mine is wired differently and will not work if i plug the other programmer in?

if i fitted the BG Up1 Do you suggest i remove the current 5Amp fuse and replace with a 3Amp?

Can i ask what potential damage i may do by swithcing the programmer to see if it is compatable, if the wiring is different?

Thanks
Ben

 

[45yearsagasman]

No1 is hot water off and is used on a Y plan system.I've seen those clocks and would just plug the new one in and check the system operation.Your boiler installation manual will have details of the correct fuse rating.