daikin vrv's

[frank]

Stupid me - I've just caught up with the postings in the Moderators Area

[Peter_1]

Me to, but that doesn't make me to change my post nor edit it.
Now it comes...........again.......all the abbreviations with 4 letters, NRIJ,.....describing the whole being of a person in just 4 letters.
A M A Z I N G
Could refrigeration be that simple......

[MRcoolingMAJIC]

Me to, but that doesn't make me to change my post nor edit it.

Hi, Peter_1.

What is the difference between changing a post and editing a post?

Thanx for the attention.

[Abe]

Is this place becoming all

schitzophrenic?????????

( I have never been able to spell that)

[frank]

Hi Raymond

Just re-visiting this old thread.

Did you manage to sort out the problem with your G series unit?

Any chance of an update - don't forget - we do site visits for reasonable reward

[Latte]

Hi Raymond

Just re-visiting this old thread.

Did you manage to sort out the problem with your G series unit?

Any chance of an update - don't forget - we do site visits for reasonable reward

Hi Frank,

First things first, ever thought of moving to Cambridge. I know a company looking for a good Daikin engineer, Unfortunatly they got me instead

Strangly got called back to the site today as the customer wants it SORTED OH REALLY !!!

Now, can't be arsed to go through previous posts to see what i've put plus my dial up is getting slower and slower so would take me all night, what i think however

VRV has a cooling rating of 162.5
Indoor units add up to 212 so in theory should have never worked. Customer response "It used to work !"

Now the reception area of the building used to be seperate rooms but now its all gone open plan so i think more duty is being put on the unit. Also the unit is getting older (Arnt we all) and therefore probably having to work harder.

Now, i would like to reclaim, vac out overnight and regas. My problem then is, If i regas to the original VRV spec, surely this is enough gas to cope with a 162.5 capacity and not 212, therefore how much extra gas should i put in.

The problem its on a fully comp contract. Therefore my company doesn't want me to spend vast amounts on gas and it not clear the fault, the customer on the other hand doesn't care how often they call us as i doesn't cost them.

Oh the joys of the job

Regards

Ray

[frank]

Raymond

First things first, ever thought of moving to Cambridge. I know a company looking for a good Daikin engineer, Unfortunatly they got me instead

What's the PAY like

My daughter lives in St Ives so I'm a regular visitor to the area

Customer response "It used to work !"

Yes but did it work as it should?

Now, i would like to reclaim, vac out overnight and regas. My problem then is, If i regas to the original VRV spec, surely this is enough gas to cope with a 162.5 capacity and not 212, therefore how much extra gas should i put in.

You just can't overcharge a system that is out of manufacturers spec and expect the extra refrigerant to make it work It is out of design - full stop (based on your previous information). What you need to do now is come up with a solution to make the system work - not to just give the customer what he wants to hear.

Why not suggest to the customer that you ought to bring in a Daikin specialist to confirm the system is not installed to manufacturers specs and that to solve the problem will cost him some money? after all it's not your fault. Plus I may get to spend the night visiting the daughter

I'll only charge the same as Space Air or Daikin UK

[Latte]

Raymond


What's the PAY like

My daughter lives in St Ives so I'm a regular visitor to the area

Hi Frank,

Better speak to cooling-gurus about that one

Looking at the site list i have, the main reception open plan area just off it have 2x40's 1x32 & 2x25. This if my math is righ is 162. There are two other units on this system on offices both 25's. I suppose the obvious answer would be to take these two off the circuit and put on their own condensing units.

Sounds simple but i expect it to be a pig of a job.

Anyway i have done my bit, i can only report what i find. Its up to those far higher up the ladder than me to come up with a solution

Regards

Raymond

[eggs]

VRV has a cooling rating of 162.5
Indoor units add up to 212 so in theory should have never worked.

I don't know too much about these things but...
Can you not size a vrv/vrf at 130% ? because not all indoor units will be switched on or running at 100% all of the time.

ie 162.5 +30% = 211 therfore,just inside the design limit.

cheers

eggs

[frank]

There are two other units on this system on offices both 25's. I suppose the obvious answer would be to take these two off the circuit and put on their own condensing units.

Unfortunately you can't put VRV indoor units on normal condensing units. Each VRV indoor unit has a built in EEV for refrigerant control and Skyair condensing units have the EEV on the outdoor.

Although you could use the 2 x 25's on a super multi but this would be more expensive than just putting in 2 new split systems.

[rbartlett]

Unfortunately you can't put VRV indoor units on normal condensing units. Each VRV indoor unit has a built in EEV for refrigerant control and Skyair condensing units have the EEV on the outdoor.

Although you could use the 2 x 25's on a super multi but this would be more expensive than just putting in 2 new split systems.

this is a R22 system so you're effed anyway...

cheers

richard

[frank]

I don't know too much about these things but...
Can you not size a vrv/vrf at 130% ? because not all indoor units will be switched on or running at 100% all of the time.

ie 162.5 +30% = 211 therfore,just inside the design limit.

cheers

eggs

Not quite Eggs.

In one respect the system can operate at 135% capacity which will mean that the indoor performance is reduced but the maximum index of the outdoor unit should not be exceeded. The high end index number relates to the 135% capacity so if you go over this then the indoor performance reduces even more as is evident by Raymond's system.

When designing a system you should calculate the indoor index numbers then select the outdoor to match - if some of your indoor units only run very little and you don't mind the temporary drop in performance then you can select the outdoor at a high index.

It's easier to understand with the selection charts in front of you

[Latte]

Hi Eggs,

I theory it could work like that, unfortunatly since they have gone all open plan the units are having to work hard all the time, especially as the receptionist thinks she's in spain and runs it at 25 all day long. I think the system would have coped before as units will have shut down in their smaller area's but no chance of that now

Regards

Fatboy

[frank]

Raymond

I found this troubleshooting guide for checking refrigerant charge

[Brian_UK]

Nice one, thanks Frank

[abdulazman]

RD
I was going to mail message you some details regarding the fault encounter but system was down. Here are the attachment. Mine are all hardcopies, hard to post the manuals down here. If you're here maybe I can hand it over to you.
Hope this things helps.