thermomate Mini Tank Water Heater ES150B - Instant Under Sink Hot

Our review of the thermomate ES150B focuses on home owners and renters who need immediate hot water at a single point of use. The bottom line: this compact 1.3 gallon point of use heater reliably delivers fast hot water at a sink with minimal installation effort, making it a practical solution for kitchens, bathrooms, or anywhere under-sink access is needed. With a corded 120V plug, foam insulation for 24 hour standby, and a simple temperature knob, it removes long waits and wasted water while fitting into tight spaces.

Key Features

• Immediate hot water: The small 1.32 gallon tank supplies instant hot water at the sink to cut down on wait time and wasted cold-water runs.
• Easy to install: A corded 120V plug and 1/2 in NPT connector let homeowners tap into the water line and mount the unit on a wall, shelf, or floor without complex wiring.
• Compact design: At about 9.7 in by 9.5 in by 14 in, the heater fits neatly under most sinks and inside cabinets where space is limited.
• Temperature control: A front knob lets users set temperatures between 68F and 140F to match comfort or plumbing needs.
• Durable lining: The enamel coated, glass lined gold porcelain interior improves corrosion resistance and supports longer service life.
• Safety features: Includes a temperature and pressure relief valve and is UL listed for safe household use.

Who It's For

This unit is best for a single-sink installation where quick hot water is needed without running a main water heater constantly, such as a kitchen prep sink, bathroom vanity, or a small utility sink. It suits renters or homeowners who want a plug-in solution that requires no special electrical work.

It is not intended for whole-house use or for large simultaneous hot water demands; anyone needing continuous high-volume hot water should look at larger capacity systems or the thermomate units with greater tank volume.

Pros & Cons

Pros

• Compact footprint fits under sinks and inside cabinets where space is limited.
• Simple plug-in 120V installation and 1/2 in NPT connection make setup quick for most DIYers.
• Fast reheating and foam insulation provide 24 hour standby and reduce wasted water.
• Durable enamel glass lining helps resist corrosion and extend service life.

Cons

• Small 1.32 gallon capacity limits use to single point applications and short tasks.
• Value impressions vary among users, with some finding it very economical and others weighing cost versus capacity.

Specifications

Model	ES150B
Tank volume	1.32 gallons
Electrical	120V corded plug
Dimensions	9.7 in W x 9.5 in D x 14 in H (approx)
Max water pressure	150 psi
Temperature range	68F to 140F
Safety	Included temperature & pressure relief valve, UL listed

Our Verdict

The thermomate ES150B is a sensible, compact point of use heater for anyone who needs fast hot water at a single sink without major installation. Its plug-in convenience, small footprint, and safety features make it good value for kitchens, bathrooms, or utility sinks, though buyers with larger hot water needs should choose a bigger tank.

Frequently Asked Questions

Can this be plugged into a standard outlet?
Yes, the unit uses a corded 120V plug so it can be used with a standard household outlet.

Will it fit under a typical kitchen sink cabinet?
Yes, its compact dimensions are intended for under-sink placement and it can be mounted on a shelf, wall, or floor inside a cabinet.

Is it suitable as a booster to an existing hot water system?
Yes, it can serve as an in-line booster to deliver hotter or faster hot water at a specific point of use.