Supermaticjames,
Having not seen the insides of a Servis washer dryer to any extent of comparison I cannot remember what the blower and heater arrangement are like but it is a possibility Servis could of sourced the blower assembly from Hotpoint or whomever made them as an actual component. Servis machines did actually have infact Hotpoint motors fitted made by GEC although the info label said Servis.
For the record Servis washer dryers didnt start to appear until the new 1986 range and were actually sourced from Antonio Merloni whom had nothing to do with Indesit. They were the Companion models, similar to the Servis Rainwaves of later years ironically.
Hotpoint had their 9900 washer dryer on the market in 1985 12 months at least before Servis had the Companions so possibly had the production plans and designs years ahead of the "true" "full panel door" Servis built Washer-Dryers that came about around 1988 to 1991