Vokera Compact 24

[DP]

I have a client who has this boiler which randomly goes to solid lockout.

I have visited the boiler several times and spoken with Vokera Tecky guys a few times as well.

On my last visit I was monitored the HW temperature at the boiler, had the Volstick on the gas valve and a U gauge to measure the burner pressure (34mbar- LPG). It did not blink once- worked every time.

Low burner rate is 6.5, both thermistor throw up a resistance of 10.04k and 10.12k at 24.4 degrees C, high limit stat 0.2 ohms, ht transformer has been replaced and well as the gas valve.

Boiler keeps on getting stuck every so often.

I would be very obliged for any information from those who have worked on this boiler

 

[weareleeds]

If it only happens in the morning it could be the meter governor sticking get him to call transco to get it changed (it won't cost anything)

 

[DP]

Thanks for the reply weareleeds. Fuel is LPG. Will bear that in mind and act accordingly

 

[Agile]

Danny, I think that you need to consider all the aspects which can cause a lockout on that model.

I dont know it very well but presumably you have the MI.

Are you sure the max burner pressure should be as high as 34 mB ? It seems too close to the 37 limit!

What about flame detection electrodes? Low res from tip to pcb? Clean and properly positioned? Checked with a megger? High value resistors on flame detection part of circuit?

Unlikely to be gas not vaporising at this time of year!

Tony