Heat Exchanger for "too cold" drinking water?

[DaveFix]

The cold mains water supply here is pretty cold all year round, much colder than where I grew up. Most of the family resort to using the hot tap for drinking water, causing the combi boiler to kick in, burn gas, then cut off before any hot water even reaches the tap. But it's just enough to get room temperature drinking water.

I'd really like to cut down on the boiler wear & tear and wasted gas.

Several years ago I installed a small drinking tap in the kitchen with microbore tubing and a charcoal filter, which nobody ever used of course. What I'd like to do is add to it some sort of heat exchanger. Something like a couple of meters of microbore copper tightly coiled using a pipe bender, and either fed through a container of water or just exchanged with the air (if that would be sufficient).

Does something similar already exist?

An easier option might be to buy a heat exchanger (brand new, boiler spare part), but I'm not convinced that would be safe to use for drinking water?

 

[muggles]

Buy a Brita filter jug and use that for your drinking water. It'll warm up to room temperature as it sits on the side.

 

[RayCaister]

Move to Sunny Norfolk. Cold water tap currently running at 19.8c.

 

[Harry Bloomfield]

Buy a couple of covered jugs, fill both with water and use (entirely) from one at a time until empty - to avoid Legionella. Only keep it a couple of days, before replacing with fresh.