Search with Wattson

Notifications

Clear all

Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!

Grant Aerona Air to Water R290 6.5 kW - Quiet Mark and Silent Running

Air Source Heat Pumps (ASHPs)

Last Post by Chris66 9 hours ago

1 Posts

1 Users

0 Reactions

6 Views

RSS

Chris66

(@chris66)

New Member Member

Joined: 6 months ago

Posts: 1

Topic starter 05/08/2026 3:10 pm [#3128]

Helping a family member with brand new installation of a Grant Aerona 6.5 kW heat pump. They, like most, just running DHW few times a day at the moment and one of the timed cycles is during off peak night time period. Unfortunately during the first 5 minutes of starting the external unit fan speed runs over 800+ rpm and the compressor working hard too. Then it drops to run at steady 400 rpm and all is quiet again.

In a quiet street and plenty of open bedroom windows as everyone tries to cool down at night, the first 5 minutes of running at the higher speed is quite noticeable even with the Grant 'Silent Mode' running. Once it drops to c 400 rpm and the compressor slows down it's fine and hardly noticeable. But annoying Silent Mode starts with 5 minutes of noticeable noise.

I can see in the Service Parameters, Heat Pump and then Heat Pump Settings it is possible to manually reduce Maximum Pump Speed from factor of 100 ( presumably the compressor) and Fan Speed from 0 to 4 by reducing rpm from preset ( with maximum of 1000 rpm).

Call to Grant Technical Support says no option to set or link Compressor / Fan speed to 'Summer' mode when just running DHW but OK to manually adjust under Service Parameters to experiment.

Anyone else with a Grant Aerona R290 been operating 'Silent Mode' over night and coming across initial ramping up at start of scheduled slot and using Service Parameters to adjust down?

Thanks in advance, Chris

Quote