Glow-worm 24 ci no hot water

[steve6501]

The boiler lost power yesterday and I soon found that the internal fuse was blown.

The boiler fired up again but now there is no hot water....with or without the heating on.

I suspect it may be the pressure sensor, but since fuses dont blow for no reason any other suggestions, please. How would I test the flow control between the rads and HW system?

No fault codes are reported.

Thanks

Steve

 

[gas4you]

I take it this is a combi? When you run a hot tap does the boiler control panel indicate that the boiler is set for dhw?

 

[steve6501]

Hi Dave

that was quick!

Yes it is a combi. The control panel (on the boiler front) when boiler is idle shows 1.2bar....thats all. If I turn up the room thermostat the boiler starts and heats the rads Ok. When i turn on the hot tap (with the rads off) nothing happens ....just hear the water flowing through

 

[gas4you]

If there is no light coming on or a symbol in the display when you run a hot tap then it points to a faulty flow sensor. I do not know which type is used on this model. I would suggest looking in the MI's.

 

[steve6501]

There used to be a link to a 24ci boiler manual in another post (it listed spare parts numbers) but the link is dead. i have lost the manual! Glow worm only show the 30ci (and several parts seem different)
There are several websites showing spares but there are numerous glowworm switches!
Thanks anyway

 

[gas4you]

If it is the flow switch is is this one Glow-worm 24CI - Parts 801910

 

[gas_man_gaz]

if iam thinkin of the right boiler the flow switch has been upgraded as they were common fault

 

[steve6501]

if iam thinkin of the right boiler the flow switch has been upgraded as they were common fault

Ha...

its has two prv's already...and the latest 'new' one 'weeps'

anyone any idea of the upgraded part no?

 

[gas4you]

The part I listed is what is given as the current flow switch.

 

[steve6501]

The part I listed is what is given as the current flow switch.

didnt see it!

Thanks!

however the 'suppliers' I have found so far show only

801189
800370
801136

 

[steve6501]

Just been looking at some very old posts on the forum.

It has occurred to me the short out the wires to the flow switch...with the water running and heating off and see if the boiler fires up. However there are 3 wires. Anyone know which two will work?

wires are pink green and white.....but it isnt clear from the wiring as they connect straight to the main pcb

 

[Rob]

It may not be a case of shorting out two wires. It may split the voltage for which you would use a DMM.

 

[Agile]

Its neither!

This sensor has a rotating magnet and a Hall effect detector!

You would need to apply an AC voltage of the required voltage and frequency.

As stated its a common fault with this boiler model.

Usually opening the flow sensor and throughly cleaning it will restore operation for at least a few days.

Tony

 

[steve6501]

Its neither!

This sensor has a rotating magnet and a Hall effect detector!

You would need to apply an AC voltage of the required voltage and frequency.

As stated its a common fault with this boiler model.

Usually opening the flow sensor and throughly cleaning it will restore operation for at least a few days.

Tony

so it could easily be the pcb at fault?

 

[Agile]

Your blown fuse has no obvious explanation.

The PCBs are pretty reliable. But it does interpret the signal from the sensor.

The flow sensors are VERY unreliable and perhaps constitute 90% of all calls to this boiler model.

Tony