The Zehnder ComfoAir 155 WM, Wme (wall mounted) and CM (ceiling mounted) are economy MVHR systems.
Please note that the Zehnder ComfoAir 155 range is an updated version of the Greenwood Vireo 155 MVHR range. The functions, filters and dimensions have remained the same.
Key features:
| Model | ComfoAir 155 Wm | ComfoAir 155 Wme | ComfoAir 155 CM | |
| Type of system | Economy MVHR | Economy MVHR | Economy MVHR | |
| Recomm. max. floor area | [m2] | 140 m2 | 140 m2 | 140 m2 |
| Max. air flow @100Pa | [m3/h] | 293/ 81 l/s | 293/ 81 l/s | 280/ 78 l/s |
| Min. air flow | [m3/h] | 70/ 19 l/s | 70/ 19 l/s | 70/ 19 l/s |
| Recommended air flow | [m3/h] | 70-149/ 19-41 l/s | 70-149/ 19-41 l/s | 70-149/ 19-41 l/s |
| Orientation | vertical, spigots at top | vertical, spigots at top | ceiling, spigots side | |
| Performance | *** | *** | **** | |
| Heat Recovery (Passive H) | % | X | X | X |
| Heat Recovery (SAP) | % | 88-92% | 84-90% | 90-92% |
| Humidity Recovery | % | X | X | X |
| Specific Electric Power (PH) | [Wh/m3] | X | X | X |
| SFP (SAP) | [W/l/s} | 0.56-1.4 | 0.50-1.3 | 0.57-0.9 |
| SAP Kitchen + max. wet rms | K+5 | K+5 | K+3 | |
| Noise | * | ** | *** | |
| Breakout noise @3m @60% | [dB(A)] | 33.1 | 32.9 | 26.5 |
| Breakout noise @3m 60m3/h | [dB(A)] | 21 | 19 | 16 |
| Breakout noise @3m 90m3/h | [dB(A)] | 28 | 26 | 20 |
| Breakout noise @3m 120m3/h | [dB(A)] | 29 | 28 | 23 |
| Breakout noise @3m 150m3/h | [dB(A)] | 31 | 30 | 25 |
| Breakout noise @3m 180m3/h | [dB(A)] | 33 | 33 | 28 |
| Breakout noise @3m 210m3/h | [dB(A)] | 34 | 34 | 30 |
| Breakout noise @3m 240m3/h | [dB(A)] | 36 | 35 | 32 |
| Breakout noise @3m 270m3/h | [dB(A)] | 38 | 37 | 34 |
| Technical | ||||
| Spigot Size | [mm] | 125 external | 125 external | 125 external |
| Weight | [kg] | 18 | 17.5 | 20.5 |
| Materials internal | PP/ EPS | PP/ EPS | PP/ EPS | |
| Type of heat exchanger | HRV | HRV | HRV | |
| Condensate connection | [mm] | 21.5 | 21.5 | 21.5 |
| Filter grade (*optional) | G3/ G4* | G3/ G4* | G3/ G4* | |
| Frost protection | [°C] | dis-balance | dis-balance | dis-balance |
| Peak winter performance | No | No | No | |
| Max power pre-heater* | [W] | X | X | X |
| Max. power cons. w/o pre-h. | [W] | 165 | 165 | 165 |
| Motors, volume flow constant | EC, Not VFC | EC, Not VFC | EC, Not VFC | |
| Summer bypass | [100%] | Yes | Yes | Yes |
| Controls | in-built controller | in-built controller | ||
| Type of controller | Ext. switch | Ext. switch | Ext. switch | |
| App control/ monitoring | X | X | X | |
| Boost activation | Auto | Auto | Auto | |
| Humidity sensor | Integrated | Integrated | Integrated | |
| CO2 sensor | No | No | No | |
| BMS capability | Yes | Yes | Yes | |
| Fire alarm integration | indirect w. relay | indirect w. relay | indirect w. relay | |
| Fault indicator | No | No | No | |
| Heating & cooling options | X | X | X | |
| Cooling module | X | X | X | |
| Max. cooling output | [W] | X | X | X |
| Max. heat output | [W] | X | X | X |
| Integrated controls | X | X | X | |
| Refrigerant | X | X | X | |
| Hot water tank | X | X | X | |
| Servicability | Made in | UK | UK | UK |
| All parts replaceable | No | No | No | |
| Fan bearings exchangeable | No | No | No | |
| Warranty – free of charge | [years] | 2 | 2 | 2 |
| Warranty – extended | [years] | 5 (through us) | 5 (through us) | 5 (through us) |
We offer original Zehnder ComfoAir 155 filters at massive discounts, to encourage users to change their filters as intended. All three versions, CA155 Em, CA155 Wme and CA155 CM use the same filters.
You choice is between standard G3 and slighly better G4 filters.
Access is behind the two removable front panels.
Please note that the ComfoAir 185 (Greenwood Vireo 185) has different filters.
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Some general product information about the Zehnder ComfoAir 155/ Vireo MVHR range.
Some informatrion about filter changes and maintenance of the Ca155/ CA185 range
If you want to know what difference there is between the Economy and Passive House MVHR systems and which ones we can recommend, clikc here.
