increase the rate delivered by mechanical ventilation (including air conditioning) units to help to optimise the efficiency of them (this is likely to reduce running costs)
gynyddu'r gyfradd a gyflawnir drwy unedau awyru mecanyddol (yn cynnwys aerdymheru) i helpu i sicrhau eu bod mor effeithlon â phosibl (bydd hyn yn debygol o leihau costau cynnal)