Glow Worm CXI 30 DHW problem

[nicksaunders]

Hi Guys,

I've got a glow worm 30 CXI which was installed in 2003, which has worked really well till about 4 weeks ago.

The problem is that the hot water is not that hot any more, so I turned it up on the boiler. The hot water then got hot but its cuts off after about 2 minutes of running. The boiler then displays a F9 fault, which flashes for about 10-15 seconds then the boiler restarts.

This fault occurs on the top 20% of the dial only. turning it down you don't get the cut out, however the water is not hot enough!.

I've checked the thermistors and these all read correctly. Putting a voltmeter across the CH flow thermistor when the problems occurs, gives a reading off 0.88 V at the point of trip.

Looking at the manual the F9 code states Pressure Sensor failure. I've put a meter on the pressure sensor and I get a steady 1.72 V, during operation and at the point of the trip.

My system was a total new one at the time of installation, and has had inhibitor in since new, I have however recently had a few raditors off and on again to decorate.

The CH works with out fault.

Can anyone help with this problem

Thanks in Advance

Nick

 

[gasgeezer]

Blocked plate heatexchanger F9 on your age boiler is a generic code.

 

[nicksaunders]

Blocked plate heatexchanger F9 on your age boiler is a generic code.

Hi,
Thanks for the Advice, is there somewhere I can find info about cleaning the Plate Heat exchanger?

Also I made a small error the boiler was installed in 2003 not 2000

Cheers
Nick

 

[nicksaunders]

I Removed the Plate Exchanger and washed out the black gunk with a high pressure hose and boiler works great.

I expect there is a better way to do this, but the hose worked for me!

Thanks for the advise

Nick