re commision hitachi ras30fxn

[tait71]

hi i have been asked to recommission a Hitachi system which has 16x ras30fxs the job was installed 6 years ago but has sat not in use until now we started by reclaiming the gas (410a) which should of weighed 59kg but we only got 50kg out out of the first unit, we have pressure tested to 21bar and its holding ok, the questions are : is this acceptable amout of refrigerant loss over6 years of standing and should i reuse the gas i have taken out and top up with 9kg?
all units have the extra gas weight written on but there are no commissioning sheets for the job so who says the correct gas charge was weighed in to start with?!

[jonjon]

I'd be tempted to start from scratch make sure you have the correct pipe lenght etc ..

[AlexAlex]

hi i have been asked to recommission a Hitachi system which has 16x ras30fxs the job was installed 6 years ago but has sat not in use until now we started by reclaiming the gas (410a) which should of weighed 59kg but we only got 50kg out out of the first unit, we have pressure tested to 21bar and its holding ok, the questions are : is this acceptable amout of refrigerant loss over6 years of standing and should i reuse the gas i have taken out and top up with 9kg?
all units have the extra gas weight written on but there are no commissioning sheets for the job so who says the correct gas charge was weighed in to start with?!

Hi, tait71

1. Pressure test for refrigerant R410 is performed at a pressure of 41 bar.

2. Recommend calculate the required amount of refrigerant. Pipe length + cooling capacity of indoor units = number of refrigerant to be charged. Do you have all the technical documentation for RAS30FXN and idoor units ?

3. If there was a leak of refrigerant R410 9kg. IMHO Better fill the conditioner with new refrigerant. Glide 410 refrigerant is small, but it is not zero.

Alex.

[assailant]

59kg of r410a :eek:

i can tell you what would happen in australia - if no leak, topping up with 9kg.
59kg of new r410a would be worth about the gdp of a small african nation.

[still learning]

did you seperate the indoor part of the system from the outdoor , if there is a leak is it indoors or on the outdoor unit?
9 kg is a lot , but only 4.1 grams a day, if i am right .
i take the indoor pipework to 41bar(410a) , and then see , hitachi may have a maximum presure for the lp switch .
i have seen a flare not leak at 20 bar , but leak at 40 bar , only a blip( using the green bubbly stuff) mind you but still a leak .
was it a 24 hour pressure test?

[tait71]

set pressure test to 25 bar and it sat there for 6 days ! measured out a couple of systems pipe runs and they have been marked up ok and most of the systems gas charges are within 6 to 9 kg diffrence so i expect them to be ok, next question is anybody know about c net boxs on these systems ? we have 200 ish indoors with 16 outdoors and 2 c net boxes, we have had a hitachei service partner out to replace and set up a replacement box( as one u/s) this was done but the next day it was auto configering every 30 mins now it just says error on the pc! and we can only see half the system, the only thing we have done today is turn off 2 outdoors to reclaim gas out off, surely doing this wouldnt stop the other 6 outdoors running if so its the daftest thing i have ever seen!
P.s no other control on systems

[Air Bear]

But it's ok now.
Steve.