Boiler cupboard smells like garlic

[Thinkcalmthoughts]

Every now and again I smell garlic like smell I've noticed it's coming from the cupboard where boiler sits in kitchen it's not all the time just now and again more so after it's been on
What is this smell as boiler has been serviced a few months ago with no problems
Or could it be the flat downstairs and the smell rising lol

I can't quite remember, but I think it's one of the anti-corrosion chemicals added to the radiator water, you may have a small leak. How often do you have to top up the pressure?

Are there any signs? Limescale or green stain on a copper pipe?

I've never had to top pressure only been in the place just over a year don't often smell it just been a few odd times and I'll check pipes later as out

does your boiler have a pressure gauge on the front? If not, it may top itself up with no action from you.

Bleed a rad into a jamjar and sniff it, then leave the jar somewhere and sniff it again in a day or two to see if it resembles the smell.