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ThermoMate 14 kW Electric, 240V Review

Name: ThermoMate 14 kW Electric, 240V
Brand: ThermoMate
SKU: B0H2NQJ89N

7.9Very good · out of 10Rated from the listing's specs, no buyer reviews yet

Written from the listing's specs, not from our own use · How we rate

We like the ThermoMate 14 kW Electric (240V) for the mix: a 3.4 GPM maximum flow, a compact 14 kW element and an element that only draws what it needs. It makes most sense for a booster under the sink of a far-off bathroom; we rate it 7.9/10 from its listing.

Price$249.99Price on Sep 30, 2026 · may have changed

Check the price on Amazon ↗Affiliate link · price and stock on Amazon

Compare side by side ↗

Specifications

Brand	ThermoMate
Category	Electric tankless water heaters
Fuel	Electric
Stated mounting location	Indoor
Stated maximum flow	3.4 GPM
Stated heating power	14 kW
Stated voltage	240 V
Temperature range	86 to 131 °F
Total current	150 A
Wire gauge	6 AWG
Stated weight	13.2 lb
ASIN	B0H2NQJ89N

Full listing title: 14kW Tankless Water Heater Electric, ThermoMate 240 Volt Instant On-Demand Hot Water Heater with Touch Control, Max 3.4 GPM Self-Modulating, ETL Certified for Residential Indoor

Listing evidence

Fuel	14kW Full listing title
Stated mounting location	Indoor Full listing title
Stated maximum flow	3.4 GPM Full listing title
Stated heating power	14kW Full listing title
Stated voltage	240 Volt Full listing title

Updated October 2026

Exact listing, ASIN B0H2NQJ89N

Rating from a published formula

Compared with its closest rivals

Two electric tankless heaters of about the same power, closest to it on our rating, each with a dated price.

Compare side by side ↗

ThermoMate 14 kW Electric, 240V

7.9Very good · out of 10$249.99 Price on Sep 30, 2026 · may have changed

Stated: 3.4 GPM · 14 kW · 240 V
Electric tankless water heaters

This product ↑

ORBEK 14 kW Electric, 240V

7.7Very good · out of 10$189.99 Price on Sep 30, 2026 · may have changed

Stated: 3.38 GPM · 14 kW · 240 V
Electric tankless water heaters

See the review ↗

Westinghouse 14 kW Electric, 240V

7.7Very good · out of 10$319.99 Price on Sep 30, 2026 · may have changed

Stated: 14 kW · 240 V
Electric tankless water heaters

See the review ↗

14 kW at 240 V

The heating power the listing states; at 240 V that's about 58 A. On our calculator's maths it gives about 2.2 GPM of 105 °F water when the tap water comes in at 62 °F, and less in winter. Enough for a kitchen or a bathroom sink.

What it has going for it

What changes at the sink

3.4 GPM max. That is the headline figure, usually at a modest temperature rise. Our calculator counts a shower at 2 GPM, so think one shower at a time.

Self-modulating. It draws only the power the flow and the setpoint need, instead of slamming every element on. Steadier temperature, and no wasted amps on a summer afternoon.

One sink or a shower?

One sink: about 2.2 GPM of 105 °F water with 62 °F tap water, on our calculator's maths. That covers a kitchen or a bathroom sink.

A shower: on paper, with warm tap water, just about (a shower takes about 2 GPM). In January it falls short.

Great for you if…

You need one shower or one sink at a time, not the whole house
The kitchen or the powder-room sink takes forever to run hot
You want the shower temperature to stay put

Skip it if…

You want hot water for the whole house: 14 kW is sized for one tap
You'd rather wait for buyer reviews: none are captured for this listing yet

Power, wiring and what's in the box

What the ThermoMate 14 kW Electric (240V) listing names:

14 kW
240 V
150 A total draw
6 AWG wire
Up to 3.4 GPM
Self-modulating
86 to 131 °F setpoint
Digital display
13.2 lb
CSA, ETL or UL mark named

Breakers and wire gauge are in the installation manual, and it overrides anything above; your electrician reads it first.

Price and cost per kW

$249.99 Price on Sep 30, 2026 · may have changed

At the price on Sep 30, 2026, each kW of stated heating power works out at about $17.86 (price ÷ stated kW, our arithmetic). That puts it in the cheaper third of the 17 point-of-use heaters we have a price and a stated power for.

Add the circuit to the budget if it doesn't plug in, and an hour of plumbing under the sink.

The button opens the exact listing (ASIN B0H2NQJ89N), where today's price, stock and seller apply.

A better fit for that tap?

Want the shower covered too? The Rheem 18 kW Electric, 240V (9.3/10) is an 18 kW whole-house unit.

Our take

The verdict

What we'd buy the ThermoMate 14 kW Electric (240V) for is a 3.4 GPM maximum flow, with a compact 14 kW element as a bonus. No buyer reviews yet, so this ThermoMate point-of-use heater has to win you over on paper. Our main reservation: it is built for one tap, and a second fixture opened at once will run lukewarm. We'd pick it if you need one shower or one sink at a time, not the whole house; otherwise, put it next to the ORBEK 14 kW Electric (240V) first.

Check the price on Amazon ↗Affiliate link · price and stock on AmazonAll electric tankless water heaters →

Living with it

Install day

6 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.

The first shower

Hot in a few seconds once the water in the pipes has passed, and the power steps up and down with the flow (self-modulating, per the listing). Set it between 86 and 131 °F.

The first winter

With 42 °F water coming in, 14 kW gives about 1.5 GPM at 105 °F on our calculator's maths. Low-flow shower heads stretch that further.

Upkeep

Clean the inlet screen and flush out scale on hard water. Our flushing and descaling guide has the routine.

The one thing we'd check first

Before the ThermoMate 14 kW Electric (240V) ships, check the tap it will feed: 14 kW suits one sink or a low-flow shower.

Before you buy

Which tap

14 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 240 V. At 240 V it needs a dedicated circuit; 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.

How it compares

How the ThermoMate 14 kW Electric (240V) stacks up against the closest alternative, the ORBEK 14 kW Electric (240V).

Criterion	ThermoMate 14 kW Electric, 240V	ORBEK 14 kW Electric, 240V
Our rating	7.9/10	7.7/10
Max flow	3.4 GPM	3.38 GPM
Self-modulating	Stated	Not stated

On our rating, the ThermoMate 14 kW Electric (240V) comes out ahead (7.9 vs 7.7), and it brings more stated flow (3.4 GPM) and self-modulating power on top. Start with this one.

Compare side by side ↗See the ORBEK 14 kW Electric, 240V review →

The score in detail

How we rated it

Spec-based rating on a 4.5–8.5 scale: 4.5 + average of the 4 criteria × 0.4. Capped at 8.5 because no customer evidence is included.

Key specifications

9 / 10

Build, warranty & certifications

7 / 10

Listing documentation

9 / 10

Fit & compatibility

9 / 10

This product has no captured buyer-review record yet, so its rating comes from the documented listing alone: four criteria scored out of 10 (key specifications; build, warranty and certifications; listing documentation; fit and compatibility), placed on a 4.5–8.5 scale. Read the full methodology.

Read the methodology →

Frequently asked questions

Is the ThermoMate 14 kW Electric (240V) any good?

We rate it 7.9/10 (very good). The rating comes from its documented listing alone, as no customer-review record is captured yet.

How much hot water can the ThermoMate 14 kW Electric, 240V deliver?

The listing states a maximum flow of 3.4 GPM and a heating power of 14 kW on 240 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.

What electrical service does the ThermoMate 14 kW Electric, 240V need?

The listing states 240 V and 14 kW. At 240 V, that is roughly 58 A. A licensed electrician checks the panel, the breakers and the wiring before it goes on the wall.

What do you get with the ThermoMate 14 kW Electric (240V)?

Its listing states up to 3.4 GPM, 14 kW for one tap and self-modulating power. 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.

What should I check before ordering the ThermoMate 14 kW Electric (240V)?

Which tap: 14 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 240 V. At 240 V it needs a dedicated circuit; 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.

Where can I buy the ThermoMate 14 kW Electric (240V)?

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.

Have you used the ThermoMate 14 kW Electric (240V) yourselves?

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.

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