The Rinnai EnergySaver EX08DTN is the better gas wall heater overall, rated 3.4 to 2.2. The Rinnai EnergySaver EX08DTN leads on warranty and controls. The Williams 1403822 Direct Vent Furnace wins on value and heat output. The Williams 1403822 Direct Vent Furnace costs $412.75 less ($989 vs $1,401.75).
For a bedroom, office or small addition where steady, quiet, thermostat controlled heat matters more than purchase price. Skip it if you need heat through power outages.
Amazon $1,401.75For a small room or cabin on natural gas that needs heat through outages at the lowest price. Add the wall thermostat and expect higher gas bills than a sealed electronic unit.
Amazon $989Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Each factor is scored 0-100 against the same fixed reference points for every direct vent gas wall heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Rinnai EnergySaver EX08DTN | Williams 1403822 Direct Vent Furnace |
|---|---|---|
| Overall rating | 3.4/5 | 2.2/5 |
| Value 30% | 17 $175.22 per 1,000 BTU ($1,401.75, 8,000 BTU) | 60 $70.64 per 1,000 BTU ($989, 14,000 BTU) |
| Heat output 15% | 0 8,000 BTU/hr | 13 14,000 BTU/hr |
| Controls 20% | 100 thermostat, blower, electronic ignition | 0 manual control, push button ignition |
| Fuel 5% | 0 natural gas only | 0 natural gas only |
| Warranty 30% | 100 5-year warranty | 0 1-year warranty |
| Rinnai EnergySaver EX08DTN | Williams 1403822 Direct Vent Furnace | |
|---|---|---|
| Heat | ||
| Venting | Direct vent | Direct vent |
| Heat type | Furnace | Furnace |
| Maximum input | 8,000 BTU/hr | 14,000 BTU/hr |
| Minimum input | 3,000 BTU/hr | - |
| Efficiency | 82% AFUE | 65% AFUE |
| Fuel and controls | ||
| Fuel | Natural gas | Natural gas |
| Thermostat | Yes | No |
| Blower | Yes | No |
| Ignition | Electronic (120 V) | Push button |
| Needs an outlet | Yes | No |
| Build | ||
| Weight | 42 lb | - |
| Warranty | 5 years | 1 year |
