Gloworm flexicom 15hx - f22 code - solutions

[dishman]

Hello,

Just restarted the boiler for the first time in a while. House was being refurbished for a number of months. Hot water and central heating have been off for quite while. No plumbing works have been carried out.

It is an open vented, heat only boiler.

Firstly the initial temp reading on the boiler is 11 degrees (current water temp I assume). I have set the desired temperature to 50.

Thermostat is set for 20. I then press the timer switch to turn the heating on, nothing, nada ziltch. No noise at all.

I then request hot water, and the boiler starts whirring, pump starts going I think. Then a louder whirring noise (coming from the pump or inside the boiler) and then an f22 code

F22 code often suggests "not enough water in the system; ch flow or return thermister wire loose, faulty, trapped or not connected to pipe properly; Air in the system; faulty pump or pump speed too fast.

I have bled all the radiators. I have also bled the pump (un-screwed the front cap) a bit of water come out. No air hissing during all of this. I have opened all thermostatic valves to full. I also gave the pump a manual spin after taking the cap off. Seems to spin quite freely.

I also checked the header tank. The hot water one is at the correct level, as is the central heating header. Gave the central heating ball float valve a push and it worked as expected.

So, thoughts?

Many thanks in advance.

 

[muggles]

Could be a thermistor fault as the fault-finding suggests. Time to call someone in with some diagnostic skills

 

[dishman]

Well, I worked out the partial reason. I realised that it may have something to do with the diverter valve. Hence the boiler thinking their was an air lock/blockage etc.

Sure enough, when set to manual, it all works. I just cannot tell if the diverter has just failed, not getting power or not getting the correct signal.

Could anything else preventing the valve from activating properly? Any methods to work out what is the cause.

A failure would be conveniently odd considering it worked last time the system was in use.

The digital timer is not very user friendly it seems. When requesting central heating only via the timer, nothing happens. Only when I select hot water too does the boiler kick in to life. I realised that this is normal for a heat only boiler (as far as I am aware). Hot water and central heating have to both be on for the boiler to work the central heating.

The thing that confused me is that on previous timers I have used, they automatically turned both on if central heating was selected. This digital one does not.