Autoterm 4D and 60mm duct

[UK-WOOZY]

been told by autoterm that coming striaght off the 4D heater direct to 60mm duct may make it overheat, i should vent off somewhere then reduce to 60. (as i dont think ill be able to fit 90mm duct through to the galley from the cockpit locker due to the small space on my boat)

thought i could go from the heater to the stern cabin via the bulkhead between the locker and cabin, then carry on from a T piece with 60mm to the galley? What fittings should i buy, i cannot find a reducer from 90 to 60 on the website

thanks

 

[oldgit]

Around 1.5 metres of large diameter ducting was enough to prevent my new heater shutting down and giving the overheat code.
Purchased a reducer from eBay to connect to the existing installed ducting .
This then connected to a "T".

 

[PaulRainbow]

You might find a Y connector a better fit. If fitting a vent in the aft cabin, make sure it's adjustable, but do not have an adjustable one in the galley.