VRV Questing Under Heating Opreation

[Goodland]

hello

When in heating operation under VRV3 u can select the speed of the fan H or L on some units HH

but once i turn all the indoor units on i cannot select the fan speed, is that normal ?

it still heats good but why sometimes i can select the fan speed other not ?

btw its

VRV 3

2 out door units RXYQ8P

indoor

2 units of FXSQ125VEB
3 units of FXFQ63VEB
1 unit of FXFQ80VEB

Controller is BRC1D528

Any ideas or if there is a manual to explain all the heating operation / conditions what will the system do in each situation

Thanks in advance

[mchild]

How many BRC controllers are part of the system? You say that when you turn on All indoor units the fan selection does not work. Does that mean if one unit is not turned on then all the other units you can select fan speed? Or does it mean if more than one unit is turn on then fan speed selection does work? If units are turned off then nothing should happen if you select fan speed - so I don't really understand as the units must be on to do anything type of selection whether fan speed of heating or cooling.

When fan speed selection does not work what happens? Is that portion of the BRC screen just blank?

[Goodland]

"You say that when you turn on All indoor units the fan selection does not work. Does that mean if one unit is not turned on then all the other units you can select fan speed? "

Exactly

and 6 BRC one for each indoor unit

[mchild]

"You say that when you turn on All indoor units the fan selection does not work. Does that mean if one unit is not turned on then all the other units you can select fan speed? " Exactly and 6 BRC one for each indoor unit

So if you have five or less units turned on the fan selection can be made on each indoor unit by each BRC, but if all six are turned on then what happens? Do the individual BRC controllers go blank in the fan speed area? Does the fan speed continue to show on the individual BRC screen but nothing changes on the screen when the fan speed button is pressed? Does the pressing of the fan speed cause the screen to change but the fan speed does not actually change? Please provide details of exactly what happens when the problem occurs.

[install monkey]

run it at heat 30 and check the coil temp in setting mode 41 to see if it exceeds 33 deg- as in heating mode the indoor fan wont speed up.

[Goodland]

the speed selection is still there it does not go to blank but the fan speed doesn't change it stays to Low "actual" while you can select on the BRC H and the fan wont speed faster.

how can i check into setting mode 41 the method to go into such menu ?

[mchild]

the speed selection is still there it does not go to blank but the fan speed doesn't change it stays to Low "actual" while you can select on the BRC H and the fan wont speed faster.

how can i check into setting mode 41 the method to go into such menu ?

You really should get the service manual for that system. There are a number of steps to get into the Service Mode (similar to filed codes but a step farther) and there are several codes - 41 is just one of them. The manual will help you understand how to get the temps that Install Monkey referred to and how to read each of the temps.

[install monkey]

with the system in heat 30 hi fan, and running, hold the test button(bottom left)for 10 seconds,(displays 10) hold the test button again for 10 seconds (display 40) press temp up for (41) in display. on the display 00 is showing the remote controller sensor ,press timer up and 01 is return air temp, timer up again display 02 and that value should increase as the unit starts up from room temp to around 33deg and the fan will speed up, its normal for this value to increase to around 45deg, to revert the controller to normal pust the test button again,
good luck

[Tayters]

The Daikin VRV's I've played with take a lot longer to change over than splits. A split will change in a couple of minutes while a VRV just appears to sit there for ages. If it's a heat recovery type then the changeover box causes some delay while the pressures sort themselves out.
From my experiance when changing to heating the fan starts when the liquid/suction pipe (No. 2 and 3 under the 41 menu) reads about 37*C.

Cheers,
Andy.

[Goodland]

okay will test and see what's the temp but the testing criteria is if the temp is above 30c it wont speed if less it will speed right ?


and is that a fault or normal behaviour ?

[Tayters]

okay will test and see what's the temp but the testing criteria is if the temp is above 30c it wont speed if less it will speed right ?


and is that a fault or normal behaviour ?

Not quite if I'm reading your sentence correctly.

Temp of indoor coil must be in the upper 30's for the fan to start up. Otherwise the defrost/preheating symbol stays on. Once coil reached correct temperature (which can be deduced from settings 2 and 3 from controller in 41 menu) then fan will start up. If coil temp drops down again then fan will stop, defrost/preheating symbol lights up until coil back up to temperature.

If room is especially cold (below 15*C) then expect this cycle to repeat a lot unit the room has got some heat in it. If it's proper chilly then it'll do it all day as we all found out here in England last year when it was especially cold.

Cheers,
Andy.

[VRVIII]

I would suggest you verify 100% the total indoor and outdoor capacity, in heating mode the indoor fans will be locked on low speed when the indoor thermostat demend is greater than 130% of outdoor capacity (connection ratio >130%).

[Goodland]

I would suggest you verify 100% the total indoor and outdoor capacity, in heating mode the indoor fans will be locked on low speed when the indoor thermostat demend is greater than 130% of outdoor capacity (connection ratio >130%).

the total of the indoor units is 130% exactly, the system setup is in my first post please have a look

as for Tayters i was referring to why the system don't reproduce the selection of fan Eg: if i set the fan on H it stays low only when i load all the system up "running all of the indoor units"

[Boxer]

The system appears to be staying on pre heat.
The system is short of refrigerant.
Decant,pressure test, repair leak, evacuate and scale in correct charge.

[sweimaker]

call daikin 01932 879200 and go from there

[Goodland]

i called the after sales they are getting on wed to check the system >><< the engineer told me that i should be able to select whatever fan so there must be something wrong they will come over check it and see whats what

Thanks for your input guys will keep ya posted on what the problem will be

[mburns]

Did happen to read this today. It's in a table which is easy to understand but should help.

In heating: Hot startup control when performing a startup, or after the defrosting cycle has been
completed, the indoor fan will be controlled as to prevent cold air draft and secure the starting
performance (quick pressure build-up).
Indoor unit fan: OFF
Heating operation is turned on with remote controller.
Indoor unit fan: LL tap
Indoor unit fan: L tap
Indoor unit fan: M tap (Continuing L tap on indoor unit without M tap equipped)
Indoor unit fan: Set fan speed
Condition
A Indoor unit heat exchanger temp. > 34°C
B Indoor unit heat exchanger temp. > indoor suction air temp. +17°C
(+12°C if outside temperature is < 5°C)
C Indoor unit heat exchanger temp. > indoor suction air temp. +22°C
(+20°C if outside temperature is < 5°C)
&
• 1 minute elapsed with LL tap
OR
• Condition A is met.
• Condition B is met.
• 3 minutes elapsed after compressor startup
&
• 1 minute elapsed with L tap
OR
• Condition A is met.
• Condition B is met.
• 5.5 minutes elapsed after compressor startup
&
• 1 minute elapsed with M tap
OR
• Condition A is met.
• Condition C is met.
• 10.5 minutes elapsed after compressor

[Goodland]

they are coming to check the system on wed hopefully they will be here but i left it running for more than 2 hours and none of the indoor fans Speeded to the H speed

Temp reading of gas 41 > 02 were as the following

if the system is able to run the Fan it would be 30s sometimes 27 "thats when im not running all of the indoor units"

if i run all the indoor units which when the fans will be locked to L the temp would read
35 somtimes 42

so not sure

also i noticed that one indoor unit made a loud noise while the system defrosted and that was after running for 1 and half hour in outdoor temp of 9 c

thanks for the input

[Goodland]

they came in today and after a while with service checker they added a small amount of refrigerant which solved the issue of some indoor units not heating very well, as for the fan control under full load they are clueless so they made a follow up case and will get back to me soon :S

so lets see whats what