Trapped air, clogged pipes or broken bleeder?

[DannyW123]

Hello good people of the forum,

I am having an issue bleeding a finned tube radiator on my second story and I was hoping you all could provide some guidance.

- I have a Bosch Combi boiler (ZWB-42-3) with hydronic baseboard & finned tube radiators. 90% - 95% of the time, my boiler is only used for hot water as I have a heat pump that works fine on all but the coldest days of the year.
- I'm actively remodeling my first-story powder room and this weekend I removed a different finned tube radiator. At the guidance of a plumber friend, I drained the system, temporarily capped the supply & return of the discarded radiator with ball valves. It's a one-pipe system with Monoflow tees so capping this section should not be the source of the issue.
- I repressurized the system (currently at ~1.4 Bar) and bled the system and everything is working fine except for the radiator in the second story bathroom.
- At the recommendation of my plumber friend, I tried to force bleed the system but it did not fix the issue.
- When I try to bleed the radiator, I can't get any air to come out.
- The supply to my second story radiator is hot in the basement but seems to be getting stuck at a 90-degree elbow in the basement. The pipe running up my wall (through the area I'm renovating) is cold. See pictures for details.

My plumber friend has a newborn so I'm trying my best not to keep pestering him. Thought I would try here before reaching out to him again. Any advice would be greatly appreciated.

Let me know what you all think.

Thanks for the help,
Dan

 

[Fitter30]

When opening the bleeder starts to heat? Get water or air out of bleeder? If you don't know what type of air removal device you have or take a pics of boiler and related piping around the boiler and expansion tank.