TYPE OF PLANT: INDIVIDUAL, CENTRALIZAED OR COLLECTIVE
A CMV heat recovery plant for more residential units can be realized in different ways, each with positive aspects and possible contraindications: the best solution can not be determined in advance, but you have to evaluate project by project.
INDIVIDUAL CMV (dedicated plant for each apartment, completely independent)
It allows a fully independent operation, ideally integrated with air quality probe (CO₂, VOC / CO₂, R.H.) which acts on the fan speed, in combination with thermal bypass device (required by 01/01/2016). Each user is responsible for its own operating costs, in case of several apartments can be interesting to evaluate the total cost of system installed with the other methods (centralized or collective).
It is not necessary to have the chimneys (renewal and expulsion) on the roof, unless local context requires it.
CENTRALIZED CMV (one centralized unit to service more apartments or utilities)
Energy recovery, thermal by-pass and ventilation are centralized, with clear advantages: best overall efficiency, easy maintenance and less noise (unit positioned in a technical room or on the roof).
On the other hand, the bypass is centralized (cannot consider the different exposure of apartments) and the system is less flexible for users with different working (temperature and presence). Eventual probe of air quality takes into account the average conditions. Provide insulation of riser main pipes (part of the heat recovery circuit).
NOTE: to compensates any imbalances caused by a different load / operation of an apartment is recommended a plant management at a constant pressure to ensure constant flow rate to the individual user, combined with variable volume dampers with manual or automatic control (air quality probe).
COLLETTIVE CMV (Autonomous passive heat-recovery and 2 centralized fans to service more apartments or utilities)
By centralizing ventilation (one each riser pipe) I achieve best overall flow efficiency, easy maintenance and less noise (fans positioned in the technical room or on the roof); ideal for constant load utilities, it is likely a cheaper plant costs (more beneficial with the increase of the number of apartments).
On the other hand, absence of thermal by-pass and less flexible for users with different working (temperature and presence). Consider isolated riser main pipes to prevent condensation (drip, mold). Do not detect the status of filter clogging (centralized hour counter as alternative).
NOTE: to compensates any imbalances caused by a different load / operation of an apartment is recommended a plant management at a constant pressure to ensure constant flow rate to the individual user, combined with variable volume dampers downstream of passive heat-recovery (heat exchanger and filters), with manual or automatic control (air quality probe).
INDIVIDUAL
CENTRALIZED
COLLETTIVE
