Mitsubishi Electric CRHV-P600YA-HPB, Service Handbook

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[
II
Restrictions ]
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HWE1312A GB
6. Minimum and maximum water flow rates
A low flow rate will not only compromise the performance of the unit but also increase the water temperature difference be-
tween the periods when the unit is in operation and when the unit is stopped. A high flow rate will cause the pipes to corrode.
Adjust the circulating flow rate so that the difference between the inlet and outlet temperatures will be between 3 ºC and 10
ºC. Refer to the table below for the standard, minimum, and maximum flow rates.
The hot water flow rate will be considered appropriate if the difference between the inlet and outlet water temperatures is be-
tween 3 ºC and 10 ºC.
 If the temperature difference is less than 3 ºC
Decrease the flow rate.
 If the temperature difference is more than 10 ºC
Increase the flow rate. Check the pipes for air pockets, and make sure that the pump has enough capacity to sustain appro-
priate water pressure in a given water circuit.
7. Maintaining the appropriate amount of water in the water circuit.
(1) Amount of water in the water circuit
Shortage of water in the circulating water circuit may shorten the operation time of the unit or cause large fluctuations of water
temperature. The table below shows the minimum allowable amount of water in the water circuit. If the piping length is too
short to secure this amount, install a cushion tank to ensure that the circuit has enough water in it.
(2) Calculating the amount of water in the circuit
The amount of water in the circuit can be obtained using the following formula.
Amount of water in the water circuit = Amount of water in the water Amount of water in the unit + and Amount of water
in the load-side or heat source unit
The table below shows the amount of water in the water piping per 1 m
Amount of water in the piping
The table below shows the amount of water in the unit.
Amount of water in the unit
8. Sizes and the material types of the pipes on the unit
The table below shows the sizes of the pipes.
Pipe sizes
Standard, Minimum, and Maximum flow rates
Unit: m
3
/h
CRHV-P600YA-HPB
Standard flow rate (50Hz)
Minimum allowable flow
rate
Maximum allowable flow
rate
Heating
Hot water side 10.3 3.2 15.0
Heat source side 14.7 4.5 (counter flow)
16.0
2.0 (parallel flow)
Model Minimum allowable amount of hot water ( ℓ ) Minimum allowable amount of heat source ( ℓ )
CRHV-P600YA-HPB 550 390
Pipe size
3/4B (20A) 1B (25A) 1 1/4B (32A) 1 1/2B A(40A) 2B (50A) 1 1/2B (65A)
Internal volume per meter ( ℓ /m) 0.37 0.60 0.99 1.36 2.20 3.62
Model Hot water side ( ℓ ) Heat source side ( ℓ )
CRHV-P600YA-HPB 15 10
Model Hot water side Heat source side
CRHV-P600YA-HPB R2 male thread pipe <SUS304> R2 male thread pipe <SUS304>