What it delivers
The MIZUDO FSSVKB-1 Tankless Isolation Valve Kit is a pair of tankless service valves for flushing and isolating the heater; its listing says it fits most 3/4" MNPT tankless water heaters (electric & gas).
With isolation valves on both lines, descaling is a hose-on, hose-off job; the hot-side valve usually carries the relief valve port.
Match the connection type (threaded IPS, sweat or push-fit) and size, usually 3/4 inch, to the heater and the pipe; most kits put the relief valve port on the hot side.
Other listed details: connections: 0.75 in; material: Brass; model: FSSVKB-1; fits: most 3/4" MNPT tankless water heaters (electric & gas).
The listing gives dimensions of 3 x 3 x 3 inches and pressure relief valve and 3/4" npt hot & cold water supply isolator valves in the box.
Right unit for this house?
Install it when
- New tankless installs
- Owners who flush their own heater
Look at another unit when
- Heaters whose manual calls for a different method
Strengths and trade-offs
Strengths
- Isolation valve kit
- Names most 3/4" MNPT tankless water heaters (e
Trade-offs
- Check the connection size first
Install limits
- Figures are the maker's or seller's own. Flow at a rise is our estimate from the input; gas, venting and electrical work needs a licensed professional.
Rated performance
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Model number | FSSVKB-1 | Retailer |
|---|---|---|
| Material | Brass | Retailer |
| Dimensions (seller) | 3 x 3 x 3 inches | Retailer |
| Connections | 0.75 in | Retailer |
| Fits | most 3/4" MNPT tankless water heaters (electric & gas) | Retailer |
Rival units at this flow
More descaling and maintenance kits rated for similar demand
- Watts LF-TWH-HCN-RV 3/4 Tankless Isolation Valve Kit
- Webstone P704RLF134 Tankless Isolation Valve Kit
- SharkBite 25374 Tankless Isolation Valve Kit
- TOPWAY 09020 Hot Water Recirculation Pump
Full descaling and maintenance kits spec grid · Every MIZUDO unit in the catalog
Final verdict
A sensible isolation valve kit for new tankless installs.
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