Glow Worm burner cycling on Pmax when trying to gas rate

[MethodPH]

Hi I am gas safe registered, when commissioning glow worm Ultimate 3. Have put into p.01 to gas rate and set at Pmax, but burner keeps cycling on and off rather than running at full rate, so am getting incorrect gas rate, any thoughts?

 

[ShaunCorbs]

Getting too hot so bad circulation or trvs shut

 

[MethodPH]

All TRV's are open, im wondering if as its only a small property boiler has got up to temperature and is starting to modulate down, hence giving a low gas rate. Doesnt help when I need the figures to be correct.

 

[ShaunCorbs]

Run it in hot water mode

 

[MethodPH]

have tried in hot water mode but they don't have the best water pressure so heats the water up very quickly. Was thinking of sticking it in chimney sweep mode? what do you think

 

[ShaunCorbs]

The only other way if it’s got a mag filter with valves shut this find a drain off away from the boiler connect this to a hose pipe and drain it off at the same time fill the system to keep it at the correct pressure

 

[Scott_D]

have tried in hot water mode but they don't have the best water pressure so heats the water up very quickly. Was thinking of sticking it in chimney sweep mode? what do you think

Chimney sweep isn’t max
Sounds like the boiler is oversized?

 

[snowhead]

Open all the windows and doors to loose the heat.