- Balanced;
- advantages - whole house fresh air in and stale air out with mechanically controlled ventilation
- disadvantages -
- needs to be climate specific for heat recovery or energy recovery
- difficult to get optimal results in high temperature and moisture changing climates
- may require make up air when exhaust only systems are also installed for combustion appliances
- Exhaust-only;
- advantages - removes point source moisture and particulate
- disadvantages -
- does not remove moisture or replace fresh air for whole home
- may require make up are for combustion appliances
Supply-only
- Advantages - brings fresh air to the home
- Disadvantages
- no exhaust of stale air may lead to increased moisture in the home
- particularly problematic with tight building envelopes