Slow coolant leak?

I have noticed this past summer I had to add about a quart of coolant every month. My question is what would cause a slow coolant leak and where would be good locations to check for leaks.

I have a 99 AWD astro van.

Thanks.

Water pump is where I would start. Look for a trail of deposits going up the lower radiator hose.

Ok I will check there first, thanks.

p.s. You should paint the trim on your house and send the city a bill...and then sue them when they don't pay it.

Naah.... I've got other plans....

No need to waste the paint on my house.

check the lower radiator hose too. I had a pinhole in mine that only leaked under pressure. how it got in that particular location I can't imagine.

I found my slow leak was where the control arm went into the heater control valve.

What did you find??