This is a pretty good example - now just apply it to the actual problem. The amount of currency in circulation.

Inflation isn't about the cost of goods or services actually costing more. They don't. If anything, the cost of production today is far less than it was 50 to 100 years ago because of advances in technology and automation.

It's about the value of the dollar becoming less and less - because there are too many dollars in circulation, which aren't backed by anything real to begin with. "Real" could be something which has a finite supply that we attach an arbitrary value to, like precious metals, or it could be something vitally (needed for life) necessary in today's world like wheat or oil. But for decades now, newly created currency is just an entry in the Fed's ledger book, created out of thin air, backed by nothing.

In your example both the size of the room and the heat represent aspects of currency (note I did not say "money"). The size of the room is the purchasing power of dollars leveraged against the actual effectiveness of the heat. The heat itself, is the value of the currency. The size of the room represents the price of goods.

As the room gets bigger, the heat becomes less effective (it loses value). So pumping in more heat becomes required. When more heat than necessary gets pumped in (on purpose - and it is done on purpose), the room will begin to overheat and no one will want anymore (so it loses its value again). The sane solution would be to stop pumping in more heat - but instead, the same people supplying the heat decide to enlarge the room again, because they are in the business creating heat and charging a fee to deliver it ("they" would be the Federal Reserve - or any private, western central bank).

So the room (i.e. price of goods) must be enlarged over and over again (artificially and unnecessarily) in order for a new infusion of heat to have any value to the people in the room. This in turn, requires the occupants of the room to keep forking over more money in delivery fees to keep the room at a comfortable temperature. If this becomes unfeasible, they may be forced to take out loans to have more usable heat. Now they're paying money for both the heat itself, plus interest on the loan for supplying it in the first place (and they owe it to the same people).

Once you wrap your ahead around the fact that the enlarging of the room and the supply of heat are actually controlled by the same people (who make their money creating heat and charging to deliver it), you then understand that the entire financial system we currently enjoy, is nothing but a giant, legalized system of usury. That delivery fee you owe for supplying the heat is called "interest".

This type of system will always (and is designed to) collapse at pretty regular intervals. When it does, those who control the flow of heat will shut it down, and have legal authority to confiscate the room from the occupants who took out loans for more heat, but couldn't afford to pay it back.

What makes the whole thing more insidious, is that the people supplying the heat never actually owned it to begin with, nor did they create it. It would be as if the room (once upon a time) had a natural heat supply from, say, and underground geothermal source. But some strong-armed, outside entity stepped in, capped that off, and started charging the people in the room for access to what was once naturally available - free of charge.