Variants, Output and COP
Bosch and Buderus are both part of the Bosch Home Comfort Group. Many heat pumps are therefore offered under two brand names: as Bosch Compress and as Buderus Logatherm. The model numbers look different even though they are based on the same technical platform.
| Bosch Compress | Buderus model | Generation and key difference |
|---|---|---|
| CS3800i AW | WLW166i MBB AR | new R290 entry-level series with 4, 6, 7, 10 and 13 kW |
| CS5800i AW | WLW176i MB AR | R290 series with 4, 5, 7, 10 and 12 kW; maximum 60 °C flow temperature |
| CS6800i AW | WLW186i MB AR | same output classes, but up to 75 °C flow temperature |
| CS8800i AW | WLW186i MBE+ AR | new R290 high-temperature series with 11, 13 and 15 kW |
| CS7001i AW | WLW196i AR | R410A; Bosch 5, 7, 9, 13, 17 / Buderus 4, 6, 8, 11, 14 |
| CS7400i AW | WLW196i AR S+ | R410A; optimized for low noise; Bosch 5, 7 / Buderus 4, 6 |
The suffixes are important: A WLW186i with outdoor unit WLW MB AR is not the same heat pump as a WLW186i MBE+ AR. The first belongs to the CS5800i/6800i family, while the second belongs to the new CS8800i family.
The output classes are partly named differently by Bosch and Buderus. For example, the same older device platform can be found as Bosch CS7001i AW 7 and Buderus WLW196i-6. The number in the model name is therefore not a reliable 1:1 comparison of the actual heating output.
CS5800i/6800i and WLW176i/186i
The focus of this documentation is the Bosch Compress CS5800i AW / CS6800i AW and the identical Buderus Logatherm WLW176i / WLW186i AR. CS5800i and CS6800i use the same outdoor units as WLW176i and WLW186i. Whether the system is designated as 5800i/176i or 6800i/186i is determined by the selected indoor unit and therefore, in particular, by the maximum possible flow temperature.
- Refrigerant: R290
- Output classes: 4, 5, 7, 10 and 12 kW
- Max. flow temperature: 60 °C for CS5800i/WLW176i, 75 °C for CS6800i/WLW186i
- Efficiency: A+++ at W35; SCOP up to 4.77 at W35 and 3.64 at W55
Outdoor unit
Maximum heating output and COP of the 5 output classes:
| Type | Bosch | Buderus | A-10/W35 | A-7/W35 | A+2/W35 | A+7/W35 |
|---|---|---|---|---|---|---|
| 4 kW | AW 4 OR-S | WLW-4 MB AR | 3.63 kW 2.70 |
3.92 kW 2.89 |
4.31 kW 3.21 |
4.99 kW 3.59 |
| 5 kW | AW 5 OR-S | WLW-5 MB AR | 5.45 kW 2.59 |
5.42 kW 2.51 |
6.43 kW 2.91 |
6.80 kW 3.16 |
| 7 kW | AW 7 OR-S | WLW-7 MB AR | 5.86 kW 2.23 |
6.71 kW 2.36 |
7.09 kW 2.83 |
7.97 kW 3.07 |
| 10 kW | AW 10 OR-T | WLW-10 MB AR | 9.99 kW 2.72 |
9.57 kW 2.47 |
11.66 kW 2.84 |
12.67 kW 3.00 |
| 12 kW | AW 12 OR-T | WLW-12 MB AR | 11.82 kW 2.46 |
11.56 kW 2.43 |
12.61 kW 2.64 |
12.90 kW 2.71 |
Sources: Bosch AW 4-7 OR-S, Bosch AW 10-12 OR-T
Indoor unit
The indoor units differ according to the maximum possible flow temperature and the integrated tanks.
Max. flow temperature
| Type | Bosch | Buderus |
|---|---|---|
| 60 °C | CS5800i AW | WLW176i |
| 75 °C | CS6800i AW | WLW186i |
Tank
| Type | Bosch | Buderus |
|---|---|---|
| without tank | 12 E | E |
| 70l buffer tank | 12 MB | TP70 |
| 16l buffer and 180l DHW tank | 12 M | TP180 |
Other model families
Parts of this documentation can also be applied to the following air-to-water heat pumps. However, depending on the generation, the refrigerant circuit, hydraulics, control system, menu labels and the entities available via EMS-ESP differ.
Bosch CS3800i AW = Buderus WLW166i MBB AR
The Bosch Compress 3800i AW and the Buderus Logatherm WLW166i MBB AR are the new price-oriented model family.
- Refrigerant: R290
- Output classes: 4, 6, 7, 10 and 13 kW
- Max. flow temperature: up to 75 °C; up to 70 °C at an outdoor temperature of −10 °C
- Efficiency: A+++; SCOP up to 5.14 at W35 and 3.87 at W55
The series is intended for single-family homes and small multi-family homes in new builds and existing buildings. The small outdoor units have one fan, while the two larger devices have two fans. Instead of a rotary piston compressor, this model family uses a scroll compressor, which is somewhat more efficient but cannot modulate down as far, which could lead to more frequent cycling.
| Design | Bosch | Buderus | Integrated tank |
|---|---|---|---|
| wall-mounted | AWEi | E | none |
| Tower | AWMi / AWMHi | T180 / T180 HK | approx. 180 l domestic hot water tank |
AWMHi or T180 HK adds a second mixed heating circuit.
Sources: Bosch Compress 3800i AW, Buderus Logatherm WLW166i MBB AR
Bosch CS7001i AW = Buderus WLW196i AR
The Bosch Compress 7001i AW and the Buderus Logatherm WLW196i AR belong to the same older device family with R410A.
- Refrigerant: R410A
- Output classes: Bosch 5, 7, 9, 13 and 17; Buderus 4, 6, 8, 11 and 14
- Max. flow temperature: 62 °C
- Efficiency: A++ at W55; SCOP up to 5.16 at W35 and 3.70 at W55
| Design | Bosch | Buderus | Integrated tank |
|---|---|---|---|
| wall-mounted | AWE / AWB | E / B | none |
| floor-standing with buffer tank | AWMB | TP120 | 120 l buffer tank |
| Tower | AWM / AWMS | T190 / TS185 | approx. 180–190 l domestic hot water tank |
AWMS or TS185 additionally has a solar heat exchanger.
Sources: Bosch Compress 7001i AW, Buderus Logatherm WLW196i AR
Bosch CS7400i AW = Buderus WLW196i AR S+
The Bosch Compress 7400i AW and the Buderus Logatherm WLW196i AR S+ are the low-noise variants of the older R410A family. Depending on the year of manufacture and market, the designation CS7401i may also appear in technical documents.
- Refrigerant: R410A
- Output classes: Bosch 5 and 7; Buderus 4 and 6
- Max. flow temperature: 62 °C
- Efficiency: A++ at W55; SCOP up to 5.1 at W35 and 3.58 at W55
| Design | Bosch | Buderus | Integrated tank |
|---|---|---|---|
| wall-mounted | AWE / AWB | E S+ / B S+ | none |
| floor-standing with buffer tank | AWMB | TP120 S+ | 120 l buffer tank |
| Tower | AWM / AWMS | T190 S+ / TS185 S+ | approx. 180–190 l domestic hot water tank |
AWMS or TS185 S+ additionally has a solar heat exchanger.
Compared with CS7001i/WLW196i, the main optimizations concern sound deflection, the refrigerant circuit, and compressor and fan operation. The selection is therefore limited to two smaller output classes.
Sources: Bosch Compress 7400i AW, Technical data Bosch CS7400i AW (PDF), Buderus Logatherm WLW196i AR S+
Bosch CS8800i AW = Buderus WLW186i MBE+ AR
The Bosch Compress 8800i AW and the Buderus Logatherm WLW186i MBE+ AR form the new high-output high-temperature model family for existing buildings:
- Refrigerant: R290
- Output classes: 11, 13 and 15 kW
- Max. flow temperature: 75 °C
- Efficiency: A+++ even at W55; SCOP up to 5.4 at W35 and 4.13 at W55
| Design | Bosch | Buderus | Integrated tank |
|---|---|---|---|
| wall-mounted | AWEi D | E | none |
| floor-standing with buffer tank | AWMBi D | TP70 | 70 l buffer tank |
The new MBE+ outdoor unit must not be confused with the previous WLW-MB outdoor units of the CS5800i/6800i or WLW176i/186i family. Instead of a rotary piston compressor, this model family uses a scroll compressor, which is somewhat more efficient but cannot modulate down as far, which could lead to more frequent cycling. The manufacturer data specifies a minimum output of 4.0 kW for MBE+ at A2/W35.
Sources: Bosch Compress 8800i AW, Buderus Logatherm WLW186i MBE+ AR