The Application of A2L refrigerants

Currently, many refrigerants have greenhouse effects. According to the Kigali Amendment, countries are phasing out some old and high GWP(global warming potential) refrigerants. For example, most residential air conditioners have switched to R32 refrigerant, which has less than half of the GWP of the previous refrigerants once leaked. However, this refrigerant is mid-flammable. The risk is low for residential air conditioners due to the small refrigerant charge amount, but we must be more cautious in commercial applications. For this reason, we provide a whole set of solutions: the refrigerant concentration in the air is sensed by the refrigerant leakage sensor(A2L sensor), and once the limit value is exceeded, the alarm will be generated through the "Mitgation board"  from Sanhua and the air conditioning system will be shut down. Japan has legislated that from 2025, commercial VRF air conditioner can use R32 refrigerant, but must with safety shut-off valves. The safety shut-off valves can isolate the indoor and outdoor parts of the A/C system once a refrigerant leak is detected, preventing flammable refrigerant from continuously entering the indoor area. Sanhua's EBV electric ball valve stands out among many industry solutions and is currently the most widely adopted shut-off valve solution.

Redefining the 5hp 4-way reversing valve:

There is a common practice in the industry that when mentioning a 5hp (used for air conditioning/heat pump) 4-way reversing valve:, people tend to assume it's the SHF-20 valve. However, this usage carries significant risks. First of all, the backgound of selecting a 5hp with a SHF-20 valve can be traced back to the era of R22 refrigerant. But today, the use of R410A is already very widespread. Nevertheless the capacity of the compressor remains similar, the 4-way reversing valve's capacity has greatly increased. When using R32, the 4-way reversing valve's capacity is more than 50% higher than that of R22. 

In other words: The 5hp system is still of the same capacity, but the SHF-20 valve is way much oversized today.

Secondly, the compressor's heating capacity will be reduced drawmatically in low-temperature applications. Combining both factors, the problem of oversizing has become quite serious. If other aspects of the system design are not properly considered, it may lead to the clog(fail-to-swith) of 4-way reversing valve.

In other words: The SHF-20 valve is no longer the same as before, and the 5hp system is also different.

According to our continuous tracking of 4-way reversing valve market failures in recent years, fail-to-switch accounts for 80% of the total number of defects, and a large part of it is due to the mismatch between the system and the valve. Therefore, Sanhua launched the SHF-20GR 4-way reversing valve. We have redesigned the capabilities of the SHF-20GR valve, which can better match the 4~6hp system when used in R410A or R32 AC/heat pump systems.