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singaman
15-05-2009, 10:36 AM
Hi
Can someone tell me how to check a vrv system with only a set of manifolds and a tong available?
Suppose the unit has a standard and an inverter compressors. The complaint is room not cold. No fault is shown and system is running. Can I use the same method to check like the normal system? That means to check the suction and discharge pressures and also the running amperes of the compressor.
Thanks

Sridhar1312
15-05-2009, 10:57 AM
Check the dry bulb & wet bulb at return air room air and grill temperatures in the indoor unit where you are getting complaint.
Then go to the outdoor and check

singaman
15-05-2009, 11:16 AM
Thanks Sridhar
What i meant is can i use the mentioned method to check the right pressures and operating ampere like the non VRV system

icecube51
17-05-2009, 05:28 PM
it depend on wat brand you are working on. if it is a Daikin,or Mitsubishi you need a service tool for PC. if it is a hitashi it is possible to work on whitout. you need to now some basics of vrv first. need the lenght of the tubes,the basic amount of refrig and the surplus to add. then you can reweigh the total an correct wats wrong.
than,and only then you can besure of the refrig side thats wright and look for other problems to the system.

Ice

singaman
20-05-2009, 01:46 PM
Hi Ice

Thanks for the information.Yes i do know basic of VRV. Limited I should say. What i really want to know is to perform a normal check using the basic manifold and tong meter to confirm enough gas and to replenish if necessary. Brands are Daikin and Sanyo.
Hope to hear from you.

Thanks again

sinewave
20-05-2009, 07:24 PM
to confirm enough gas and to replenish if necessary.


:confused:

Simmo
20-05-2009, 10:22 PM
Have you checked discharge superheat's??????

eggs
20-05-2009, 11:39 PM
I don't know much but i do know this, with respect to VRV/VRF thingies.
Manifolds are only useful for gassing the things up in the first place and for getting out of the van to impress impressionable clients, along with every other clever tool in the van when the things aint working.

Get busy with a simple thermometer and interrogate the controller before you get the clever tools out.

Eggs

El Padre
21-05-2009, 08:26 AM
If its a Daikin, and there are hard wired controllers fitted, you can perform a test run so that all units are in cooling with a thermostat on demand and then check the coil sensor readings via code 41 on the controller, if there is a shortage of refrigerant you will see an increase in coil temperature on the furthest fancoils.

Cheers

kcuk
21-05-2009, 04:02 PM
also what you can do is turn all the other units off on the line and leave only that one working then, make sure the condenser is still running, then like the fella above me said check 41 in test mode to see if you are getting any refrigerant down to the last unit, if the compressors are running and, other units are working ok when they are switched on, check the tev itl be either on the bsv box above a ceiling somewhere, if it hasnt this then it is using its own tev in the indoor unit, sometimes these get stuck open and closed.

but check the operation with all other units of first then post back your results.

techguy
21-05-2009, 04:41 PM
HI Singa ,

See attached.

T

techguy
21-05-2009, 04:42 PM
HI Singa,

Thats for SANYO VRF , :-)

T

singaman
24-05-2009, 07:51 AM
Hi guys
Thanks for all the suggestions. Will carry out your valuable ideas.
Regards

icecube51
24-05-2009, 08:32 PM
if you do a lot of work on the daikin VRV , maybe you could considder the service-checker from daikin. then you have everything you need to do service on the daikin units.

Ice

singaman
25-05-2009, 04:39 AM
Hi Ice
are you referring to compressor checker ?
Pls enlighten me.
Thanks