in-line heater test?

[MartinOz]

Re: in-line heater test?

Un-soldered the relay.

There are no tracks directly underneath the relay, so the heat had obviously just destroyed the copper track on the other side of the board.

Soldered on a jumper wire to the leg in question on the relay. Drilled a larger hole through the damaged PCB to allow jumper wire to fit through. Soldered other end of jumper wire back to the terminal pins where the push fit connector (to the heating elememt) is soldered to the board. Re-soldered rest of relay legs.

We have heat! 😆 Not sure how long it will last, but no signs of further heat damage after several wash cycles. I will keep checking it though!

Thanks for the advice guys!

Martin

[cockney steve]

Re: in-line heater test?

Pleased to hear that you worked it out.
It’s likely the increased cross-section of your jumper-wire is a much better heat-shunt than the original printed track.
To put it another way, my guess is that the relay is still showing high resistance/and/or burning of the contact-points.

I’d suggest you replace the relay fairly soon!

[MartinOz]

Re: in-line heater test?

It is a 5 min job to check the PCB, so I will check it again after another 10 cycles or so.

If it shows signs of heat damage, I’ll order a new relay (assuming I can find somewhere that sells them!).

Thanks for the concern.

Martin

[cockney steve]

Re: in-line heater test?

Martin, you’re being too simplistic and not absorbing the info!

to spell it out:-
ESTABLISHED…. relay is marginal, therefore contacts deteriorate rapidly

poor contacts= high resistance =heat

you have now installed a “heat-shunt”

DEDUCED:- relay will still get hot
solder-joint will no longer act as a thermal fuse.
it is highly likely the relay casing/base will melt

CONCLUSION……your “temporary repair COULD start a fire /wipe out the circuit-board / kill the heater.

check Maplin /RSWWW.COM /Rapid electronics / do a search on “electronic component suppliers.

You’ve established that , as yet, no irreversible damage has been done….don’t turn it into a writeoff ! Get a relay, sort it properly. 😆

[KG]

Re: in-line heater test?

Thank you for this great thread – I have the same problem on my AEG dishwasher.

I have located a relay, which has the required specs (fixes the heat issue) and which seems to be a drop in replacement.

Can any of you experts help verify if this component is what many of us are looking for:
http://uk.farnell.com/finder/36-11-9-01 … dp/1217372

[cockney steve]

at a quick glance, that looks fine.

correct coil-volts.
rated to carry more than the 230V mains

current through contacts rated at 10 amps.

I didn’t check wether the requirement is for a changeover relay ,or for a single-throw one(presume it’s the latter)….so you’re good to go.

[KG]

Re: in-line heater test?

It works!

The above Finder relay was delivered in a day.
I removed the old relay and soldered the new one in (exact same footprint), and soldered the lead at the burnt out pad to the adjacent trace.

I now have hot water again – and the issue with the marginal relay should be resolved 😀

[Rich44]

Re: in-line heater test?

My previous look at the pcb was, I admit, less thorough that it could have been. 😳

This time I removed all the wires and removed the pcb from the plastic housing and sure enough there is a burnt out terminal

This is right under the NAIS JS1-12V AJS1311 10A 125V~ Relay 😀

___________________________________________________________

Would it be possible to re-post the pictures please: I think I have the same problem

Richard D

[Author]

Posts