Our Greenstar Utility 32/50 has just been serviced, and, unlike Millsy, the engineer couldn't get it to the MI figures. Should I be worried? Readings on the invoice are:
CO2 14.2 (MI 12.0)
Flue temp 87 (MI 85)
Smoke 0
Pump 115 (MI 120)
CO 88
He did a thorough job, taking over an hour to clean both heat exchangers, and cleaned the condensate trap. Nozzle used is right, 1.10 45S. I'm just a bit concerned the CO2 is high - what does this mean in terms of efficiency? Not sure if it's relevant, but flue is conventional, approx 10m high from boiler in basement to top of chimney.
One other odd thing - when I rang to confirm the booking, they said they might need to replace the flexi oil lines (£18 each). In our last house they weren't replaced in 15 years and never gave any problem. Is this something new dreamed up by OFTEC?