
Waterway 2.5" x 2" Pump Union Assembly, 400-5990
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Quick overview
- Waterway part 400-5990 The Executive pump union assembly, sold as an assembly rather than loose pieces.
- Sized 2.5 in. by 2 in. The 2.5 in. side meets the pump, the 2 in. side takes the plumbing.
- Executive pumps Listed for Waterway Executive 48 frame and 56 frame pumps.
- Serviceable connection Unions are what let you pull a pump for service without cutting pipe.
- Where leaks start A weeping union is usually a hardened o-ring or an overtightened nut, and both end in a replacement.
- Hand tight Union nuts are designed to seal by hand, and a wrench is what cracks them.
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2.5" x 2" Pump Union Assembly, 400-5990
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Product details
The Waterway 400-5990 is the 2.5 in. by 2 in. pump union assembly for Waterway Executive pumps, in both the 48 frame and 56 frame versions.
What a union does
Unions are the reason a pump can be pulled off the pad in a few minutes instead of a few hours. Each one gives a threaded, sealed joint that comes apart by hand, so the pump can be removed for service or replacement without cutting into rigid pipe and rebuilding the plumbing afterward.
The usual failure
Unions leak in two ways. The o-ring hardens with age and heat until it no longer seals, or the nut has been cranked down with a wrench and cracked. Both are common, and both end with a replacement union. When you fit this one, thread the nut down by hand only; the joint is designed to seal on the o-ring, not on torque.
| Brand | Waterway |
|---|---|
| Manufacturer part number | 400-5990 |
| UPC | 806105082145 |
| Type | Pump union assembly |
| Size | 2.5" x 2" |
| Fits | Waterway Executive 48 frame and 56 frame pumps |
| Part type | Pool pump part |
| Shipping weight | 0.2 lb |
| Ships | Parcel |
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Questions and answers
What people ask about this product, answered by our pool techs.
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