Programmer Wiring

24 Jan 2009
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United Kingdom
I have a glow worm ultimate boiler and a drayton tempus 3 programmer. Need to replace programmer as only parts of the digital digits appear, making it hard to read settings. Bought a LP522, which is suppose to be compatible with the tempus 3. Took off the tempus 3 but the wiring is not as it should be. It is:
yellow/green = E
black = N
Yellow wire and Red wire = L
No wire in 1
No wire in 2
blue wire in 3
red wire in 4

Tried to keep wiring as it is, but the hw and ch lights come on but no hw or ch.
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Have you moved any wires at all and has ther been any work done recently? (honesty really helps)

secondly does the HTG and DHW work if you replace the old programmer?
No wires have been moved.

I put the old programmer back on and it is working. Just cant set times due to digits missing, which is why I am trying to replace it.
check the wires are secure in the connectors, could well be a loose neutral wire, which may give you neons but no power.
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Have tried again to reinstall the new programmer. Have made sure that all connections are tight. Again same problem. Neon lights on both CH and HW, boiler makes a slight noise, but does not fire up. Have put old programmer back on and its all working again. Really stumped on this one.
You have a duff new programmer, that would be my first conclusion.

it is not as unlikely as you imagine.

I assume you did not take off the backplate as they are identical :eek: .

I do not understand why you think the wiring is wrong. Do you have a three port motorised valve, or a couple of two ports?
I have a couple of two port valves. When I looked on old wiring diagram for tempus 3 it does not have 2 wires connected to the Live. Is there any way of checking programmers?
Isolate mains power to system and either place a link between L and 4 or simply move the wire across to L.

Leave the programmer off and ensure room stat is calling for heat.

Reinstate power and boiler should fire for heating.

By doing this you have bypassed the programmer, if the boiler fires then you have a faulty new programmer if it does not then further investigation would be required.

Try this first and post results
i had this when i fitted my new programmer, i forgot to set the dip switch on the back which selects Gravity hot water or fully pumped. i left it on fully pumped and the lights came on but no heating or hot water- the boiler didnt fire up. as soon as i swapped the dip switch over it all worked fine
Bypassed programmer and boiler fired up. Faulty programmer. Will get another.

Thanks for everyones help. Much appreciated.

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