Looks like simply replace A. Hose looks expanded there, not sure of size.
Has anyone installed a lower rad hose heater for cold weather start-ups? Was thinking of one for my R60 to use in conjunction with an oil pan heater for those really cold nights. Anyone know the hose size (1”....25 mm or so?) and where best to install?
can anyone see any potential issues?

 

Ok, so I guess nobody has done this? Does anyone have access to the coupler (A) shown, or hose, that could provide a dimension? Looks like the hose is flared a bit where it attaches to that connector - should be an ideal location for an inline heater?

For those in the sunny (and warm) south here is what an inline heater looks like - this one by Temro:


Temro inline heater for lower radiator hose.

 

I have recently installed a lower rad hose heater on my 2013 R56. This is the only post I can find in regards to lower rad hose heaters in Mini’s. Seems to do the trick and a relatively easy install as they have a habit of placing rad hose unions in convenient locations. I installed a 1-1/4” temro model, picked up from the local NAPA for $50ish. Looking to upgrade to a newer Countryman in the near future. Let me know if you ever had any success? I’d be interested to know the size difference and if you had any issues. It has only been a week that I have had it installed; had gotten a thermostat related engine code but that is most likely due to my insufficient system bleed or at least that’s what I’m hoping..

 

I didn't end up going with the in-line heater but it should be possible on the R60 - as you mention there are lots of connections on the heater hose system. I ended up using an oil pan heater instead and it has worked very well for me. We had some -35 to -40 weather for a couple of weeks lately and the Mini started every time, only plug it in for 1-2 hours. I also installed a trickle charger as I found the battery (even a new one) discharges a bit when cold, computer senses that and impacts the fan speed (no higher speeds)....just when you need it!
Where are you? I'm in northern Canada.
I also just purchased a lower engine cover to help contain the heat a bit better, but haven't installed it yet.

 

Located in Banff. I’ve been rocking a 150W oil pan heater and Temro battery blanket for the past two winters. It’s a good combo but sometimes it still struggles in -40 even after being plugged in all night. The plastic thermostat housing worries me; having seen many posts about leaks and they’re not cheap. Recently replaced it after CEL came on in the summer. With a good scanner; you’ll see a permanent P0128 or P173B code that translates to “coolant below operating temperature”. So a $50 insurance policy for the cooling system should be worth it. Thanks for your time. I’ll post on here when I upgrade to the R60. Cheers!