Product images: Amazon listings
Written from the listing's specs, not from our own use · How we rate
If you're after 3.5 kW for one tap, the Rheem 3.5 kW Point-of-Use (120V) delivers, with a 5-year warranty on top. It suits a booster under the sink of a far-off bathroom, and its sibling listing, the Rheem 18 kW Electric (240V), holds #1 in our whole-house electric tankless water heater ranking.
These are sold as variants of one listing family. Each variant has its own page.
| Brand | Rheem |
|---|---|
| Category | Electric tankless water heaters |
| Fuel | Electric |
| Stated heating power | 3.5 kW |
| Stated voltage | 120 V |
| Temperature range | 80 to 140 °F |
| Wire gauge | 10 AWG |
| Stated warranty | 5 years |
| ASIN | B0CJJY7RZZ |
Full listing title: Rheem 3.5kW Point-of-Use Thermostatic Tankless Electric Water Heater - 120V
| Fuel | 3.5kWFull listing title |
|---|---|
| Stated heating power | 3.5kWFull listing title |
| Stated voltage | 120VFull listing title |
Rated from the listing's specs, no buyer reviews yet
What it's made for: a booster under the sink of a far-off bathroom.
Two electric tankless heaters close to it on our rating, each with a dated price.
The heating power the listing states; at 120 V that's about 29 A. On our calculator's maths it gives about 0.6 GPM of 105 °F water when the tap water comes in at 62 °F, and less in winter. That's a hand-wash sink with a low-flow aerator, not a kitchen tap.
What it has going for it
80 to 140 °F. The setpoint range per the listing. Above 120 °F at the tap is scalding territory for kids, so most homes set it lower.
5-year warranty. 5 years, per the listing. Read what it needs from you: many makers ask for a licensed install and regular flushing to keep it valid.
One sink: about 0.6 GPM of 105 °F water with 62 °F tap water, on our calculator's maths. That's a hand-wash sink with a low-flow aerator.
A shower: no. A shower takes about 2 GPM, and 3.5 kW gives about 0.6 on a warm day.
What the Rheem 3.5 kW Point-of-Use (120V) listing names:
Warranty & support: 5-year warranty, as stated in the listing.
That is the maker's promise, not ours. Keep the invoice, register the Rheem 3.5 kW Point-of-Use (120V) if the maker asks, and read the install conditions: many tankless warranties need a licensed install and regular flushing.
The installation manual has the last word on breakers and wire size; show it to your electrician before you order.
At the price on Sep 30, 2026, each kW of stated heating power works out at about $42.56 (price ÷ stated kW, our arithmetic). That puts it in the pricier third of the 17 point-of-use heaters we have a price and a stated power for.
Unless it plugs into an existing outlet, an electrician runs the circuit; the plumbing under the sink is the smaller job.
The button opens the exact listing (ASIN B0CJJY7RZZ), where today's price, stock and seller apply. Sizes and variants of the same family often sit at different prices.
Want the shower covered too? The APUS 27 kW Electric, 240V (7.4/10) is a 27 kW whole-house unit.
A kitchen sink, not a hand basin? The ThermoMate 14 kW Electric, 240V (7.9/10) is rated 14 kW.
Our take
We like the Rheem 3.5 kW Point-of-Use (120V) for 3.5 kW for one tap and a 5-year warranty. No buyer reviews yet, so the Rheem 3.5 kW Point-of-Use (120V) has to win you over on paper. The catch with this Rheem point-of-use heater: no word on the breakers it needs or the flow. We'd pick it if the kitchen or the powder-room sink takes forever to run hot; otherwise, put it next to the xwdzswgs 3,000 W Under-Sink (110V) first.
10 AWG wire, the unit on the wall next to the old tank's spot, water in and out. Under a sink or on the wall beside it, close to the tap it feeds.
Hot in a few seconds once the water in the pipes has passed. Set it between 80 and 140 °F.
With 42 °F water coming in, 3.5 kW gives about 0.4 GPM at 105 °F on our calculator's maths. Low-flow shower heads stretch that further.
Clean the inlet screen and flush out scale on hard water. Our flushing and descaling guide has the routine.
Before the Rheem 3.5 kW Point-of-Use (120V) ships, check the tap it will feed: 3.5 kW suits one sink or a low-flow shower.
3.5 kW warms one sink or one low-flow shower, not two. Decide the fixture first, then check the flow it needs. Our point-of-use guide explains the trade-off.
It runs on 120 V. A dedicated outlet or circuit may still be needed; an electrician confirms the breaker and the wire.
Small units need a minimum flow to switch on. Ask the seller for that figure if you have low-flow aerators.
Electric units scale too, mostly at the inlet screen and the element. Our flushing and descaling guide covers the routine.
How the Rheem 3.5 kW Point-of-Use (120V) stacks up against the closest alternative, the xwdzswgs 3,000 W Under-Sink (110V).
| Criterion | Rheem 3.5 kW Point-of-Use, 120V | xwdzswgs 3,000 W Under-Sink, 110V |
|---|---|---|
| Our rating | 7.0/10 | 7.0/10 |
| Heating power | 3.5 kW | Not stated |
| Breakers | Not stated | 32 A total |
| Warranty | 5 years | Not stated |
Both score 7.0/10. The Rheem 3.5 kW Point-of-Use (120V) brings more power (3.5 kW) and a longer stated warranty (5 years), so it has the edge on paper.
We rate it 7.0/10 (good). The rating comes from its documented listing alone, as no customer-review record is captured yet.
The listing states a heating power of 3.5 kW on 120 V. The headline flow is a mild-weather number: with cold winter water coming in, the same unit gives you less. Read the maker's flow chart at your winter rise, or let our flow-rate calculator do the sums.
The listing states 120 V and 3.5 kW. A licensed electrician checks the panel, the breakers and the wiring before it goes on the wall.
Its listing states 3.5 kW for one tap and a 5-year warranty. These are the seller's figures, not our measurements: how steady the temperature is in your shower and how it copes with your winter water can't be read from a listing.
Which tap: 3.5 kW warms one sink or one low-flow shower, not two. Decide the fixture first, then check the flow it needs. Our point-of-use guide explains the trade-off. Power: it runs on 120 V. A dedicated outlet or circuit may still be needed; an electrician confirms the breaker and the wire. Activation flow: small units need a minimum flow to switch on. Ask the seller for that figure if you have low-flow aerators. Scale: electric units scale too, mostly at the inlet screen and the element. Our flushing and descaling guide covers the routine.
We link to the exact listing on Amazon, where today's price, stock and seller apply. It is an affiliate link, and it has no effect on the rating.
No, we haven't used it ourselves. Everything on this page comes from its listing, read line by line and weighed with our published formula.