Ideal use for bottom fittings on air separators.

SuperJ

Whenever I see an expansion tank or makeup water piped to the bottom of an air separator I always cringe a bit. I know that most of them aren’t actually specified as dirt separators, but wouldn't they tend to collect debris in the expansion tank? Anyone else have any qualms about piping the expansion tank into the bottom versus maybe a drain valve to purge any sediment that may have collected there?

EBEBRATT-Ed

It could be an issue, but a closed loop system shouldn't be that dirty. However, some systems are dirty. You could put a ball valve under the air separator a tee under the ball valve with the expansion tank on the tee and a boiler drain on the branch of the tee. With the ball valve open give it a flush and flush out the air separator. With the ball valve closed give it a flush and the air pressure in the ex tank will push any debris out the boiler drain.

In addition it gives you a way to isolate and drain the expansion tank to check the air pressure

hot_rod

I like Ed’s idea maybe a cross for fill valve on one side, expansion on the other and ball drain straight down for flush

SuperJ

Thanks guys, good ideas. I like how they don’t really add too many extra valves and fittings. I tend to want ball valves everywhere, but the costs really add up.

SuperJ

BTW, I re-piped my home system with a drain going straight thru a Tee off the bottom of my Discal, and I do collect a small amount of debris (just little flecks since I'm using an old used Polaris tank). If I had the tank hanging off the bottom the expansion tank would be collecting crap that might not come out.

Fill and expansion tank are T'd off to the side and drain straight down.