The BOS-200 is the larger 2.2 L member of Yamato's BOS stainless oil-bath line — a solid stainless-steel bath chosen for good temperature stability and durability, with a remote PID controller for safe hands-off operation. The bigger φ170 × 140 mm bath and 425 W heater heat larger flasks to a 250 °C ceiling in synthetic, distillation, and rotary-evaporation work. This is the 115V variant; the 220V sibling is the BOS-210, and the glass-bath equivalent (for visibility) is the BOG-200.
Key Specifications
| SKU | BOS-200 |
| Type | Oil bath, stainless steel, remote PID controller |
| Bath capacity | Recommended (no load) ~1.7 L; maximum ~2.2 L |
| Internal bath dimensions | φ170 × 140 mm |
| Temperature control range | Room temp. +5 °C to 250 °C |
| Temperature setting range | 0 °C to 260 °C |
| Temperature accuracy | ±0.3 °C (at 200 °C, when stirring) |
| Control system | PID control, Pt100Ω sensor, digital ▲▼ set (1 °C units) |
| Heater | Stainless-steel tube heater, 425 W |
| External dimensions | φ185 × 240 × 180 mm (bath); controller 150 × 90 × 45 mm |
| Weight | ~3.4 kg total (bath + heater + controller) |
| Voltage / power | 115V, 50/60 Hz, 4.5 A (220V sibling = BOS-210) |
Application Profile
The 2.2 L stainless oil bath targets larger flask-scale synthetic and distillation chemistry where temperature stability and durability matter:
- Larger round-bottom flask heating in organic synthesis and reflux
- Rotary-evaporation and distillation heat sources requiring stable oil temperatures to 250 °C
- Reactions above the water-bath ceiling — oil enables set points well past 100 °C
- Stirred reactions — the bottom indent seats a magnetic-stirrer hot plate (compatible with Yamato MFD800/MFH800), and a PTFE stirrer and arbor ship with the unit
- Demanding or long-run heating where a rugged solid-stainless bath is preferred over glass
Choose the stainless BOS bath when temperature stability and durability are the priority (250 °C ceiling); choose the glass BOG bath when visibility of the flask and oil level is more important.
Design Architecture
A remote PID controller (150 × 90 × 45 mm) drives a 425 W stainless-steel tube heater via triac zero-cross switching, holding ±0.3 °C at 200 °C when stirring with a Pt100Ω sensor. Separating the controller from the hot bath lets the operator set and read temperature safely at a distance. An indent at the bath bottom integrates a magnetic-stirrer hot plate and prevents the bath from sliding. Optionally, a flask-inserted sensor pairs with the in-tank sensor for tighter control at the reaction site, and a triple-system configuration is available. Safety layers include self-diagnostic sensor-error detection, automatic overheat prevention, an independent overheat prevention device, a heater guard, and a 6.3 A short-circuit/overcurrent fuse.
Frequently Asked Questions
What temperature does the BOS-200 reach? The BOS-200 has a temperature control range of room temp. +5 °C to 250 °C (setting range 0 °C to 260 °C), holding ±0.3 °C at 200 °C when stirring via PID control and a Pt100Ω sensor.
Is the BOS-200 available in 220V? No. The BOS-200 is the 115V variant; order the BOS-210 for 220V.
Does the BOS-200 come with oil? No — oil is not included. Add roughly 1.7 L (max ~2.2 L) of a suitable heat-transfer/silicone oil rated for your target set point.
Should I choose the stainless BOS-200 or the glass BOG-200? Choose the stainless BOS-200 when temperature stability and durability are the priority (250 °C ceiling); choose the glass BOG-200 when visibility of the flask and oil level matters more.
Can the BOS-200 be used with a magnetic stirrer? Yes. An indent at the bath bottom seats a magnetic-stirrer hot plate (compatible with Yamato MFD800/MFH800) and keeps the bath from sliding; a PTFE stirrer and arbor ship with the unit.
Ordering & Configuration
In the box: heater guard (1 set), arbor (φ12 × 90 mm, 1), PTFE stirrer (~φ8 × 50 mm, 1), connector cap (1), and tag-attached cable ties (3).
Add oil separately. The recommended fill is ~1.7 L (max ~2.2 L) of a suitable heat-transfer/silicone oil for the target set point — oil is not included.
Confirm voltage. BOS-200 is 115V; order BOS-210 for 220V. For a glass bath (visibility) at the same 2.2 L class, choose BOG-200 (115V) / BOG-210 (220V).
Catalog-priced; no quote gate. Confirm voltage at checkout.
Warranty: Per Yamato standard terms.
Yamato BOG/BOS oil bath family:
- BOG-100 / -110 — 1 L glass · BOG-200 / -210 — 2.2 L glass
- BOS-100 / -110 — 1 L stainless
- BOS-200 (this product) — 2.2 L stainless, 115V · BOS-210 — 2.2 L stainless, 220V
