Haier AU242FHBHA Installation Manual page 22

Others and Test Run
Containers for R407C refrigerant must be marked with R407C and a brown Stripe.
R407C and R22 refrigerants cannot share the same instrument distributor and filling pipes.
2. Calculating method of refrigerant concentration
Calculate concentration as follows.
(1) Calculate the total amount of refrigerant of each cooling system(kg) = Refrigerant
charge amount of one system of outdoor unit + Additional refrigerant charge amount
Refrigerant charge amount of one system of outdoor unit means: Refrigerant amount when leaving factory
Additional refrigerant charge amount means: Additional refrigerant amount charged according to piping
length and piping diameter during site operation.
(2) Calculate space of the smallest room installing indoor unit
(3) Calculate the concentration of refrigerant
Total charge amount of cooling system
Space of the smallest room
installing indoor unit
3. Method of avoiding refrigerant concentration to exceed critical concentration
(1)Open an vent opening
Open vent opening on both top and bottom part of door which connects to outdoor.
Each opening is no less than 0.15% of the room space. Vent opening could also be opened on the wall directly.
(2)Decease charge amount of refrigerant Shorten piping length.
Let indoor unit and outdoor unit nearer to shorten piping length so as to decrease refrigerant amount.
Decrease indoor and outdoor unit capacity
Constitute one outdoor unit with several units.
Then each outdoor unit capacity decreases and refrigerant amount is less.
(3)Set the scavenger fan by oneself
In order to keep refrigerant concentration below critical concentration, user can use the scavenger fan all the
while to let in fresh air.
In condition of non-stop scavenging cannot be executed, let scavenger fan correlative to leakage alarm
(In case of leaking, scavenger fan works immediately.) (As follow)
Outdoor unit
Indoor unit
NOTE : (for adding R407C refrigerant)
Example of scavenging system
Scavenger fan and its correlative leakage alarm
Gas leakage alarm should be set
at the place where leaked
refrigerant gather together.
The room where refrigerant leakage takes place.
(Refrigerants will all leak out.)
Refrigerant concentration0.3(kg/m
scavenge port
21
3
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