Vaillant 28 pro

[buckley plumb]

Fitted this yesterday. 6m of 22mm pipe. 20 mb at meter 18.5 at gas valve test point so gas pipe ok and working pressure . All analyser readings spot on.put gas rated a bit low even in p01 25.5kw. Only thing I noticed was flow rate was only 8 L/min. So boiler may modulate down but Po1 should ignore modulation. Anyone had this. Vaillant said not to worry

 

[wattsie1987]

Fitted this yesterday. 6m of 22mm pipe. 20 mb at meter 18.5 at gas valve test point so gas pipe ok and working pressure . All analyser readings spot on.put gas rated a bit low even in p01 25.5kw. Only thing I noticed was flow rate was only 8 L/min. So boiler may modulate down but Po1 should ignore modulation. Anyone had this. Vaillant said not to worry

Not had it on the pro but regularly gas rate new 831s or 832s now at 2 kW under and inlet and fga fine. As long as I'm getting 35 degree rise at 10lpm I don't worry 10% under in MI's is ok. There is scope to ramp it up a little because of the +/- 1.0 but I've personally never bothered.