What it delivers
The APUS AP-ADSK180-H18 Electric Tankless Water Heater is a whole-house electric tankless rated at 18 kW on 240 volts. Its listing gives a maximum flow of 4.4 GPM.
Flow depends on how cold the incoming water is. Our estimate from its input: 2.7 GPM at a 45°F rise, falling to 1.8 GPM at 70°F, which is less than one 2 GPM shower on a cold-climate winter day. Size it to your fixtures.
At 240 volts 18 kW is about 75 amps. The maker calls for 2 x 40A breakers. A licensed electrician confirms the panel, the service and the wire before it goes in.
Electric tankless units need no venting and no gas, and work best where inlet water stays mild, because every degree of rise costs flow.
Also on the listing: material: Sheet Metal with Insulating Paint; model: AP-ADSK180-H18; warranty: 2 Year Manufacturer Warranty.
The listing gives dimensions of 11.42 in (W) x 13.7 in (H) and a weight of 15.2 lb.
Warranty, per the listing: 2 Year Manufacturer Warranty.
Right unit for this house?
Install it when
- One shower at a time in mild climates
- Homes with no gas service
Look at another unit when
- Panels without spare capacity
- More than 1 shower at once in cold winters
Strengths and trade-offs
Strengths
- 18 kW
- Up to 4.4 GPM
- No venting or gas line
- Breakers stated by the maker
Trade-offs
- Draws about 75 A
- Weak at a large winter rise
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 | AP-ADSK180-H18 | Retailer |
|---|---|---|
| Dimensions (seller) | 11.42"W x 13.7"H | Retailer |
| Power | 18 kW | Retailer |
| Voltage | 240 V | Retailer |
| Product weight | 15.2 lb | Retailer |
| Warranty | 2 Year Manufacturer Warranty | Retailer |
| Material | Sheet Metal with Insulating Paint | Retailer |
| Max flow (maker) | 4.4 | Retailer |
| Breakers (maker) | 2 x 40A breakers | Retailer |
Rival units at this flow
More electric tankless water heaters rated for similar demand
- WINTEMP YQ-WN18K 18 kW Electric Tankless Water Heater
- Orbek ET018 18 kW Electric Tankless Water Heater
- SIVUATEK TSB-180 18 kW Electric Tankless Water Heater
- VancEpic RE18K-C 18 kW Electric Tankless Water Heater
Full electric tankless water heaters spec grid · Every APUS unit in the catalog
Final verdict
A practical whole-house electric tankless for one shower at a time in mild climates.
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