Potty Lynx

[Agile]

I had to go to an 83 y.o. lady with a leaking boiler.

This was more of a social responsibility as the boiler was well beyond its expected life expectancy ( like the owner ).

After spending some time sorting out the leaking bits I noticed that it had another fault.

On DHW the display showed a green led on the DHW coluum but as soon as it warmed up the hotter indications were on the CH coluum. Also the CH temp control was operating on DHW.

For interest only does anyone know what has failed in the control cct ?

We have full PCB spares in stock but little call for them as most people prefer to replace the boiler as thats more appropriate now.

Tony

 

[andsam]

You may have checked this Agile but are all the diodes in a straight line and not bent over. If these are OK I would suggest it is the Distribution PCB.

Andy.

 

[geoff@cetltd]

did the dist'n board get wet ?

either the comparators on the 407685 or a problem on the 407686 - difficult to say without outting iton a test rig and checking them out

 

[Agile]

This apparently happened some while ago according to the 83 y.o.

I was called after an identified person, probably the son, tried to replace the PRv and it leaked badly. The electronic fault was some time previous.

Presumably the temp A to D comparator is the same but switched to each display according to the function in use. Its that switching medium that has failed.

Note that the lowest ( coldest ) led operates correctly on the DHW display until it warms up and its the CH control which now controls the DHW temp !!!

This is a totally understandable pcb with SN 74 logic so easy to follow !

Tony

Tony

 

[geoff@cetltd]

Some connectors, a couple of chips and a primitive power supply (well, two actually)

... which costs more than a decent computer motherboard c/w processor