New Boiler Leaked Co - Compensation?

First time posting in this subreddit - any advice very appreciated.

Friday morning myself and my partner woke feeling awful, dizzy, nauseous, headaches, and I fainted. He luckily had the brainwave that our symptoms correlate with carbon monoxide poisoning so we got out the house (with our 1 year old who seemed much better than us thank god) and erred on the side of caution thinking we were over reacting. Got a gas engineer in as soon as poss and they confirmed the boiler was leaking CO. Mine and my partner's bedroom is above the kitchen where the boiler is which explains why we felt so awful compared to our little one. I'm also pregnant so we all went to a&e to get checked and are luckily okay.

(I should add we did have a detector that came with the house but its a dual smoke/CO alarm and is out in the hallway away from the boiler and had a very high level it needed to go off, hence why we weren't alerted. We've since bought a much more sensitive one which will live next to the boiler)

However our boiler was only fitted in October 2024, brand new. They are coming to fix it for free tomorrow (been a cold couple of days) but are we within our rights to seek further compensation, from either the manufacturer if it turns out to be an item fault, or the company who fit it if it was due to a mistake they made? If so, how?