Hi, I just moved into a house where I can't for the life of me figure out how the heating system actually works. And it's noisy.
I come from a flat where I had a single piece of hardware, a Vaillant gas boiler. Not only did it work perfectly and I could easily understand it, but I could barely hear it while working.
In this house I just moved in, I have:
1) A gas boiler (Vaillant)
2) A large hot water tank
3) Not one, but two cold water tanks in the loft (a small one and a large one)
4) A thing labelled "immersion heater" (apparently turned off)
5) Other small pieces of hardware I can't identify
6) Some very complicated piping keeping all of this together
I am interested in learning how all of this is supposed to work, especially the small water tank in the loft (where water looked rather "stale" and not safe to drink), but my top priority is identifying the cause of a loud humming noise that propagates through the walls whenever the system is engaged (i.e. the hot water tank is filling up). There is no cracking, popping, clanging, etc., it is a deep, "vibrating" sound, similar to the one coming from a portable petrol generator, but louder, and making the whole house resonate.
Besides suggesting some reading material (whereby I can learn how these heating systems work - in my country of origin we have a massive outdoor/underground combi gas boiler per house, and that's it, no intermediate cold/hot water storage), can you advise on how I can diagnose this humming sound? It does not seem to come from the gas boiler nor the hot water tank, it comes from "inside" the house, and I can't find the source.
I can attach pics as needed.
Thank you in advance.