Drayton LP boiler timers LP722 LP522

[AndyPRK]

Hi.

I could have posted this in plumbing or appliances but thought this maybe the best place.

I've got a couple of these now where the CH relay won't activate. I just wondered if it was a common problem ? (given the quantity of these that must have been made)

I've fitted a new relay and it's no better.

Sometimes if I tap the unit with a screwdriver the relay will change over. Other times if the HW relay activates, it will persuade the CH relay to change over

 

[CBW]

Are these brand new units or existing? I also think it may have been better in the plumbing section as they’re likely to have come across more?

 

[stem]

Might be a loose connection on the backplate, or the backplate connections are damaged.

I'm not quite sure what you mean by "I've fitted a new relay" do you mean that you have stripped them down and replaced an internal relay?

The LP722 and 522 are 'programmers' a 'relay' is just an electric switch.

 

[JohnD]

If the relay is not operating correctly, it suggests to me low switching voltage. Does it buzz or chatter? Could there be a dirty connection, or a dry soldered joint?

Some components degrade with age.

 

[ianmcd]

it suggests to me low switching voltage

Neither of these have low voltage switching

 

[JohnD]

No, I mean, if the relay needs a voltage of (say) 200 to 250 volts to pull it, and for some reason it only received 150 volts, it would not operate reliably. But it might switch if jolted as described.

 

[AndyPRK]

It's an existing timer. 10 years old. (unit with green LED and Boost function) I think I already changed the relay once in that period though!

I changed the relay, this item:

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No it's not the backplate connections.

Yes, I was thinking it was the relay drive voltage/current.

It doesn't chatter. And it's not a solder issue, as the joints have been redone in the relay replacement exercise

 

[AndyPRK]

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lifestyle LP722 Fault

Hello everyone, im new to this. I think i have got a fault on a lifesyle LP722 controller heating not coming on unless the hot water is on. When the heating is selected the 2 port moves across and activates micro switch. 2 port is a newish item. The pump doesnt run i think the heating side is...

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HW runs fine but CH won't work. Programmer fault? - www.ultimatehandyman.co.uk