Register now or log in to join your professional community.
Cost is mainly the diasadvantage. Particularly, the need for a back-up unit because when the condenser unit bogs down the whole system would not be operational. Therefore, should that happen multiple offices or departments can be disrupted of business operation. As opposed to conventional units which are "1 is to1" and individualized in respective offices the problem is contained only in one specific location. To have a back-up unit, however, would mean double the installation cost and since VRF units are already expensive so it all boils down to costing. Otherwise, in terms of electricity consumption, installation space, etc... the VRF system is ideal.
Dear
In m opinion the system is good overall and very rapidly increasing in the market but it has the following disadvantages or you can say limitations
1. Price per ton is too high.
2. cooling heating simultaneously is limited. (2 or3 pipe system also very expensive)
3. for high rise building the system cannot be used.
4. for not so high rise building the compressor will be very big to over come additional piping and pressure loss.
5. All manufacturers are not providing this.
6. Limited BMS System and integration with IBMS System is not possible.
7. Standby system is also limited for critical areas.
8. need to increase tonnage for longer piping.
Hope this will work
very expensive
not suitable for High rise building
limited standby sysytem
potential for Refrigernat leaks
Less economizer cycle benefit may occur with the smaller ventilation system since the
ducting is sized just for ventilation.
• Use of supplementary heat may be required for quick recovery from night setback. This
can be avoided to a great extent by providing sufficient time to allow the heat pump cycle
to be used with the compressors running at maximum capacity to provide morning warm
up.
• Use of backup strip heat for space heating in cold weather would be a detriment to the
efficiency of the system. However, as indicated above in the list of advantages, speed
variation and other features help increase the heat pump capacity to offset some of the
vapor compression cycle degradation with lower temperatures. This can avoid or
minimize the need for backup heat. Integrated gas heating systems are not available as
yet as a dual fuel option.
• It may be less economical to provide high efficiency components (such as fans, or filter
systems) for many decentralized indoor units compared to the efficiency of these systems
when installed in a single larger centralized system.
Control system between outdoor and indoorunits is proprietary; this means no independentcontrols contractor can service, or repair, orupgrade the control system-you “are married” tothe manufacturer for the life of the system and Complex oil management/recovery system;approximately every 6-9 hours an “oil recovery”cycle occurs in which all compressors are forcedto full load and all electronic valves open fullyfans are reduced to minimum cfm. Cycle lasts6-8 minutes
1. Per TR Cost is High. Particularly, the need for a back-up unit because when the condenser unit bogs down the whole system would not be operational. Therefore, should that happen multiple offices or departments can be disrupted of business operation. As opposed to conventional units which are "1 is to1" and individualized in respective offices the problem is contained only in one specific location. To have a back-up unit, however, would mean double the installation cost and since VRF units are already expensive so it all boils down to costing. Otherwise, in terms of electricity consumption, installation space, etc... the VRF system is ideal.
In m opinion the system is good overall and very rapidly increasing in the market but it has the following disadvantages or you can say limitations
1. Price per ton is too high.
2. cooling heating simultaneously is limited. (2 or3 pipe system also very expensive)
3. for high rise building the system cannot be used.
4. for not so high rise building the compressor will be very big to over come additional piping and pressure loss.
5. All manufacturers are not providing this.
6. Limited BMS System and integration with IBMS System is not possible.
7. Standby system is also limited for critical areas.
8. need to increase tonnage for longer piping.
