Roth DWT 620L Oil Tank (165 gal)
Roth's EcoDWT plus 3 is a double-wall indoor oil tank: a blow-moulded polyethylene inner tank inside a galvanized steel outer tank. Because the inner tank is a moulded shape, not a box, its contents can't be worked out from the outside dimensions — Roth's own fill chart is the authority.
| Model | Roth Double-Wall Oil Storage Tank (EcoDWT plus 3) DWT 620L |
| Part / model number | DWT 620L (model designation as printed; no numeric part number shown on page) |
| Rated capacity | 165 (620) [U.S. Gal (liters)] |
| Length | 29 in |
| Width | 28 in |
| Height | 61 in |
| Min. Height | 66 in |
| Empty weight | 132 lbs (60 kg) |
| Inside or outside? | not stated (presumably outside of steel outer tank; page does not say) |
“Model ... DWT 620L ... Nom. Capacity U.S. Gal (liters) ... 165 (620) ... Length: inches (cm) ... 29 (74) ... Width ... 28 (72) ... Height ... 61 (155) ... Tank Weight ... 132 (60)” — Roth, retrieved 2026-11-01
Gallons by the inch
| Depth | US gal | Litres | % full |
|---|---|---|---|
| 3″ | 5 | 19 | 3% |
| 4″ | 9 | 34 | 5% |
| 5″ | 10 | 38 | 6% |
| 6″ | 14 | 53 | 9% |
| 7″ | 16 | 61 | 10% |
| 8″ | 18 | 68 | 11% |
| 9″ | 22 | 83 | 14% |
| 10″ | 25 | 95 | 16% |
| 11″ | 27 | 102 | 17% |
| 12″ | 29 | 110 | 18% |
| 13″ | 34 | 129 | 21% |
| 14″ | 36 | 136 | 22% |
| 15″ | 38 | 144 | 23% |
| 16″ | 40 | 151 | 25% |
| 17″ | 45 | 170 | 27% |
| 18″ | 47 | 178 | 29% |
| 19″ | 49 | 185 | 30% |
| 20″ | 51 | 193 | 31% |
| 21″ | 56 | 212 | 34% |
| 22″ | 58 | 220 | 35% |
| 23″ | 60 | 227 | 37% |
| 24″ | 65 | 246 | 39% |
| 25″ | 67 | 254 | 41% |
| 26″ | 70 | 265 | 42% |
| 27″ | 72 | 273 | 44% |
| 28″ | 77 | 291 | 47% |
| 29″ | 79 | 299 | 48% |
| 30″ | 81 | 307 | 49% |
| 31″ | 84 | 318 | 51% |
| 32″ | 89 | 337 | 54% |
| 33″ | 91 | 344 | 55% |
| 34″ | 93 | 352 | 57% |
| 35″ | 98 | 371 | 59% |
| 36″ | 100 | 379 | 61% |
| 37″ | 102 | 386 | 62% |
| 38″ | 104 | 394 | 63% |
| 39″ | 109 | 413 | 66% |
| 40″ | 112 | 424 | 68% |
| 41″ | 114 | 431 | 69% |
| 42″ | 116 | 439 | 70% |
| 43″ | 120 | 454 | 73% |
| 44″ | 123 | 466 | 75% |
| 45″ | 125 | 473 | 76% |
| 46″ | 127 | 481 | 77% |
| 47″ | 132 | 500 | 80% |
| 48″ | 134 | 507 | 82% |
| 49″ | 137 | 519 | 83% |
| 50″ | 141 | 534 | 86% |
| 51″ | 144 | 545 | 87% |
| 52″ | 146 | 553 | 89% |
| 53″ | 148 | 560 | 90% |
| 54″ | 153 | 579 | 93% |
| 55″ | 155 | 587 | 94% |
| 56″ | 157 | 594 | 95% |
Printed on the chart: “Any fuel oil storage tank can only be filled to a maximum of 95% capacity to allow for expansion when fuel is warmed. Filling above the 95% level is not permitted”
Related: when will my oil run out? · tank corrections · all manufacturer tanks. Dimensions differ from your tank? Measure it and use the tank volume calculator.
Usable capacity and full weight
Roth's fill chart limits the fill to 95% of capacity. For the DWT 620L, 95% of 165 gal is 156.8 gal (589 L).
| Item | Value |
|---|---|
| Tank weight (Roth) | 132 lb |
| Heating oil, 156.8 gal at 7.2 lb/gal | 1,129 lb |
| Total | 1,261 lb |
Give the total to the installer. The floor under the tank must carry it.
How to read the chart
- Get the level in inches from the tank gauge or from a stick reading.
- Find the reading in the first column of the chart above.
- Read the gallons in the same row.
- If the reading is between two rows, add the fraction of the difference to the lower value.
- Subtract your reserve volume to find the oil that you can use before the next delivery.
Plan the next delivery
Use your daily use to find the days until the tank reaches your reserve. Example: the tank holds 99 gal, the reserve is 33 gal (20% of 165), and you use 3 gal per day. The tank reaches the reserve in (99 − 33) ÷ 3 = 22 days. The run-out forecaster does this with your own readings.
Cite this page
Copy a reference for this page. The data on this page comes from the maker's own documents. Also cite the document in the sources list.
Sri Murugan Systems. (2026, November 1). Roth DWT 620L oil tank (165 gal) chart. tankvolumecalc.com. https://tankvolumecalc.com/tanks/roth/dwt-620l/
@misc{srimurugansystems2026rothdwt620l,
author = {{Sri Murugan Systems}},
title = {{Roth DWT 620L Oil Tank (165 gal) Chart}},
year = {2026},
month = nov,
howpublished = {\url{https://tankvolumecalc.com/tanks/roth/dwt-620l/}},
url = {https://tankvolumecalc.com/tanks/roth/dwt-620l/},
note = {tankvolumecalc.com, accessed 2026-11-01}
}Last updated 1 November 2026.
Sources and standards
- Double-Wall Heating Oil Tanks | Roth North America — spec tableRoth — manufacturerhttps://www.roth-america.com/product/oil-storage-tanks/double-wall-heating-oil-tank/not shown
- Roth EcoDWT plus 3 Fill ChartRoth — manufacturerhttps://www.roth-america.com/app/uploads/2022/03/DWT-Fill-Chart.pdf2022-03-14 (PDF metadata)
- Methodology — partial-fill formulas used for the geometric figurestankvolumecalc.comhttps://tankvolumecalc.com/methodology/
Every linked source above was retrieved and checked on 2026-11-01.