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Written from the listing and 34 buyer reviews, not from our own use · How we rate
The Eemax HA036240 (36 kW 240V) is an electric tankless heater built around 36 kW of heating power. 34 buyers rate it 4.2/5, and it suits a home without gas and with a big panel.
| Brand | Eemax |
|---|---|
| Category | Electric tankless water heaters |
| Fuel | Electric |
| Stated heating power | 36 kW |
| Stated voltage | 240 V |
| Buyer reviews | 34 · 4.2/5 |
| ASIN | B00J2N2SX8 |
Full listing title: Eemax HA036240 240V 36 kW Electric Tankless Water Heater
| Fuel | 36 kWFull listing title |
|---|---|
| Stated heating power | 36 kWFull listing title |
| Stated voltage | 240VFull listing title |
Two electric tankless heaters of about the same power, closest to it on our rating, each with a dated price.
The heating power the listing states. At 240 V it draws about 150 A. That's the line to show your electrician before anything else: the panel decides whether this fits, not the shower.
Warm tap water: where it comes in around 62 °F (much of the South), 36 kW gives about 5.7 GPM of 105 °F water on our calculator's maths. That's two 2 GPM showers at once.
A cold January: where it comes in at 42 °F, it's about 3.9 GPM, one 2 GPM shower at a time. Up north, that's the figure to size against, and it's why the honest answer is sometimes a second unit or gas.
What the Eemax HA036240 (36 kW 240V) listing names:
For the Eemax HA036240 (36 kW 240V), the installation manual settles the breakers and the wire.
At the price on Sep 30, 2026, each kW of stated heating power works out at about $21.20 (price ÷ stated kW, our arithmetic). That puts it around the middle of the 27 whole-house electric tankless heaters we have a price and a stated power for.
The online price is the heater alone. New double-pole breakers, heavy-gauge wire and the electrician's visit are extra, and an older panel may need an upgrade first.
The button opens the exact listing (ASIN B00J2N2SX8), where today's price, stock and seller apply.
Panel short on spare amps? The Rheem 18 kW Electric, 240V (9.3/10) is rated 18 kW, about 75 A at 240 V.
Only one sink far from the heater? The ThermoMate 14 kW Electric, 240V (7.9/10) is a 14 kW point-of-use unit.
Want it to draw only what it needs? The WINTEMP WN-36kW Electric, 240V (8.1/10) is self-modulating, per its listing.
Our take
The best thing about the Eemax HA036240 (36 kW 240V) is 36 kW of heating power. Only 34 buyers have rated this Eemax electric tankless heater so far (4.2/5), so treat the score as an early read. The catch with the Eemax: no stated self-modulation, while most picks here have it. We'd pick it if your house has no gas and a 200 A panel with room to spare; otherwise, put it next to the Eemax EEM24036 (36 kW) first.
New breakers, the unit on the wall next to the old tank's spot, water in and out. An electrician does the panel side.
Hot in a few seconds once the water in the pipes has passed. Set it, then leave it.
With 42 °F water coming in, 36 kW gives about 3.9 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.
Buyers give it 4.2/5, a solid record, slightly below our ranked picks' 4.3 average. Only 34 reviews so far, and our formula damps averages built on fewer than 50.
Before the Eemax HA036240 (36 kW 240V) goes in your cart, check your panel: 36 kW at 240 V is roughly 150 A, so an electrician should look at the panel first.
Take a photo of the panel label (main breaker size and free slots) and send it to the electrician with the listing. Our electrical requirements guide explains what they will look for.
On our calculator's maths, 36 kW gives about 3.9 GPM with 42 °F winter water and 5.7 GPM with 62 °F water. Our flow-rate calculator does it for your region.
Hardwired 240 V work needs a licensed electrician and often a permit. Our install cost guide shows what usually ends up on the quote.
Hard water still builds up on the elements and the inlet screen. Our flushing and descaling guide covers the routine.
How the Eemax HA036240 (36 kW 240V) stacks up against the closest alternative, the Eemax EEM24036 (36 kW).
| Criterion | Eemax HA036240, 36 kW 240V | Eemax EEM24036, 36 kW |
|---|---|---|
| Our rating | 5.6/10 | 5.6/10 |
| Voltage | 240 V | Not stated |
| Self-modulating | Not stated | Stated |
| Buyer reviews | 34 · 4.2/5 | None captured |
Both score 5.6/10. The Eemax EEM24036 (36 kW) adds self-modulating power.
We rate it 5.6/10 (fair). It is based on 34 buyer reviews averaging 4.2/5 and the specifications stated in the listing.
The listing states a heating power of 36 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.
The listing states 240 V and 36 kW. At 240 V, that is roughly 150 A. A licensed electrician checks the panel, the breakers and the wiring before it goes on the wall.
Its listing states 36 kW of heating 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.
Your panel: take a photo of the panel label (main breaker size and free slots) and send it to the electrician with the listing. Our electrical requirements guide explains what they will look for. Your winter flow: on our calculator's maths, 36 kW gives about 3.9 GPM with 42 °F winter water and 5.7 GPM with 62 °F water. Our flow-rate calculator does it for your region. The install: hardwired 240 V work needs a licensed electrician and often a permit. Our install cost guide shows what usually ends up on the quote. Scale: hard water still builds up on the elements and the inlet screen. 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 and 34 buyer reviews, read line by line and weighed with our published formula.