What it delivers
The Hydro Smart HSTWSO34NPT Tankless Isolation Valve Kit is a pair of tankless service valves for flushing and isolating the heater.
With isolation valves on both lines, descaling is a hose-on, hose-off job; the hot-side valve usually carries the relief valve port.
Before ordering, check the heater's fitting size and whether you want threaded, sweat or push-fit connections; the hot-side valve usually takes the pressure relief valve.
Other listed details: material: Brass; model: HSTWSO34NPT.
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
Trade-offs
- Fit depends on your valves
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 | HSTWSO34NPT | Retailer |
|---|---|---|
| Material | Brass | Retailer |
Rival units at this flow
More descaling and maintenance kits rated for similar demand
Final verdict
A sensible isolation valve kit for new tankless installs.
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