Puma 80

[park]

What fault would a failed wax capsule generate in a potterton puma 80

 

[Vic Spanner]

What fault would a failed wax capsule generate in a potterton puma 80

Not to sure what you mean by generate.But if you mean fault then this
1. Diverter wax capsule...No heating or a very limited flow to rads
2. Hot water wax capsule...Hot water will only trickle out even when heated up in heat exchanger.

 

[park]

What fault would a failed wax capsule generate in a potterton puma 80

Not to sure what you mean by generate.But if you mean fault then this
1. Diverter wax capsule...No heating or a very limited flow to rads
2. Hot water wax capsule...Hot water will only trickle out even when heated up in heat exchanger.

Thank you that has answered my question..............cheers

++++++++++++++++++++++++++++++++++

OK next question
Combi located next to kitchen sink, turn on hot tap, water cold after running off 2 washup bowls water gets warm.
Yet hot water OK when heating on ?

 

[ChrisR]

DHW flowsitch - red light on PCB?

 

[Softus]

What is the entire set of symptoms of the problem(s) that you wish to receive help in solving?

 

[park]

What is the entire set of symptoms of the problem(s) that you wish to receive help in solving?

As indicated above.
Turn on the kitchen sink hot tap, water runs warm for a couple of seconds then runs cold for a minute or so before getting warm again. The boiler is located adjacent to the kitchen sink.
If the central heating is on, and the boiler is firing then on turning on the kitchen hot tap the water is hot and not a problem

 

[ChrisR]

DHW flowsitch - red light on PCB?

 

[Softus]

As ChrisR says, first check that the red LED is showing when you open a hot tap. If not then there's a problem with the flow switch.

If you get a red LED, then your problem could be one or more of many things. The first test I would do would be to see if the burner modulates up when the flow switch operates. If not then it could be either gas valve or PCB.

With care you can check whether or not there is a voltage at the gas valve when the flow switch operates. You'll probably find other topics covering this.

Since checking the PCB is within the scope of most DIYers, you could choose to this next. Remote all power from the boiler, remove the bottom part of the case, remove connections from the PCB, remove the PCB and check both sides for damage and signs of dry joints.

If it's not an electrical problem then in all likelihood you have a faulty diverter valve.

 

[park]

As ChrisR says, first check that the red LED is showing when you open a hot tap. If not then there's a problem with the flow switch.

If you get a red LED, then your problem could be one or more of many things. The first test I would do would be to see if the burner modulates up when the flow switch operates. If not then it could be either gas valve or PCB.

With care you can check whether or not there is a voltage at the gas valve when the flow switch operates. You'll probably find other topics covering this.

Since checking the PCB is within the scope of most DIYers, you could choose to this next. Remote all power from the boiler, remove the bottom part of the case, remove connections from the PCB, remove the PCB and check both sides for damage and signs of dry joints.

If it's not an electrical problem then in all likelihood you have a faulty diverter valve.

Thank you for that info, will try that

 

[Agile]

Since checking the PCB is within the scope of most DIYers, you could choose to this next. Remote all power from the boiler, remove the bottom part of the case, remove connections from the PCB, remove the PCB and check both sides for damage and signs of dry joints.

I would definately NOT advise doing it this way!

Firstly more work and secondly removing/replacing the plugs induces bad solder joints.

All you need to do is remove the four screws holding the PCB and gently pull it downwards from the top to inspect the underside leaving all the plugs connected!

This is with the power isolated from the boiler!

Tony

 

[park]

I would definately NOT advise doing it this way!

Firstly more work and secondly removing/replacing the plugs induces bad solder joints.

All you need to do is remove the four screws holding the PCB and gently pull it downwards from the top to inspect the underside leaving all the plugs connected!

This is with the power isolated from the boiler!

Tony

But if I isolate from the power how will I know if a joint is dry or not. What am I looking for?

 

[Softus]

Firstly more work and secondly removing/replacing the plugs induces bad solder joints.

Firstly, it's about 1 minute more work.

Secondly, no it doesn't. Bad solder joints are created, not induced. If there's a latent fault that you find by removing a connector, then all the better.

Thank you for that info, is that a Red LED on the PCB ?

Yes.

But if I isolate from the power how will I know if a joint is dry or not.

Eh? There's no choice about this one. Remove all power.

What am I looking for?

Dry joints tend to be dull instead of bright, and can also show signs of cracking. You'll get a feel for what a good quality solder joint should look like if you remove the case from your Hi-Fi amplifier.

 

[park]

Having removed all the power, checked the PCB for poor joints, found one, what do I do. Can I re-solder the suspect joint? Or do I buy a new PCB

 

[Softus]

Do you have a soldering iron with a stand, a solder pump, some solder, a strong light, and good eyesight (or reading glasses)?

If so then you can resolder it.

 

[Agile]

Secondly, no it doesn't. Bad solder joints are created, not induced. If there's a latent fault that you find by removing a connector, then all the better.

I must disagree with you.

The unreliability of the Puma PCB originates because the holes drilled in the substrate are too large and do not hold the pin in place tightly.

This results in the pin being held by the solder joint which fails as a result of thermal cycling and insertion/removal of the plugs.

Tony