Archive for February 14th, 2012

Watts 9D-M3 Backflow Preventer Valve: Failure & Aggravation

This Watts 9D-M3 Backflow Preventer Valve feeds water into our furnace, provides an overpressure relief, and prevents heating loop water from re-entering the potable water supply.

Watts 9D-M3 Backflow Preventer Valve

Watts 9D-M3 Backflow Preventer Valve

The vertical pipe leads downward near the floor, underneath which sits the small plastic bucket I provided to catch the occasional drip. Recently we had an all-hands scramble to soak up a pool of water spreading across the floor from the overflowing bucket, across the aisle, and below the shafts-and-rods-and-tubes-and-pipes storage rack. Evidently the occasional drip became a steady drip while we weren’t watching; not a catastrophic flood, but far more water than we want on the floor.

This is the inlet valve, which is basically a flapper. You can’t see the fine cracks around the central mount, but they’re all over the inner half of the ring.

Watts 9D-M3 - Inlet valve

Watts 9D-M3 - Inlet valve

And this is the outlet valve, which has pretty much disintegrated. Note the outer rim peeled back under my thumb:

Watts 9D-M3 - Outlet valve

Watts 9D-M3 - Outlet valve

A complete new valve is $40, in stock and ready for pickup at Lowe’s, but all I really needed was the failed rubber flapper valves, which they don’t carry. A few minutes of searching reveals the Watts 0886011 Repair Kit, which has all of the interior parts.

Pop Quiz: How much does the repair kit cost?

Answer: Starts at $38 plus shipping and goes up from there. Cheap aftermarket kits run $20 and up, but they’re all out of stock.

Now that, party people, is the sort of thing that ticks me right off.

Perhaps the local HVAC / plumbing supply stores have such kits in stock? To quote: “They may exist, but we don’t have them.”

I don’t see any way to homebrew new flapper valves, so it’s off to Lowe’s we go…

It would seem to me that these things shouldn’t fail after a mere decade of service. I thought that about the CdS flame sensor that crapped out in the middle of a sub-zero January cold snap while I was at Cabin Fever some years ago, too.