Daikin vrv 3 cooling only convert to heat pump

[Stefce]

Hi i have a RXQ5 vrv3 that i converted to a heat pump by installling a 4way valve and an eev..i have few questions i would like to get help if possible
1. As far as the pcb it shows the same pcb is on my unit EB0668(A) with the pcb on the heat pump unit which has an Y in the model number RXYQ5 newer replacement pcb is Seb11050 according to the service parts ..what i dont understand is why i cant make the unit heat even with the right dip switches appplied..it always shows cool fan and dry and no heat..i tried installing a manual switch on the unit which selects cool..fan or heat .and it works for fan only and than cooling and drying but doesnt switch to heating.. My unit has a manual switch PCB installed even if its a cooling only unit which makes no sense..
2. My unit had a RT6 probe which is for defrost even if its not shown on the diagram on the unit..also when power up it checks the eev on the outside unit.and so on..no error message and so..but i cant make it to heating.. What was odd it was that the DS1-3. Switch was out from factory and clearly on the service manual it says that when a virgin pcb is used this switch should be On for cooling only and off for heat/cool..and it was off..
3. I am looking trough the net and i see same pcbs layouts as mine are listed for sale as new. But have different designation like seb0768..can i buy it and try since i have run out of ideas..whats so different on the pcbs and have different designations..its the same pcb as mine when i compare it. And according to the parts manual it says i need a replacement instead of my EB0668 a SEB11050 as a newer part..
4. Isnt there a master reset for the pcb so i can return it to stock??is it possible to lock a pcb for cooling only from the factory with a factory eprom flash or so ,and now no matter what i do i cant use it with heating..?pcb locked to cooling only?
5. One other odd thing is that my setup is one outside unit and 2 wall indoor units with 2 wired remotes..i cant seem to make one slave and the other main Rc..they only come out of booting if they are both master RC..when one is selected as Sub Rc it stays on checking connection and doesnt come on..i checked on the outdoor pcb ..the units sees as 2 units connected to it..and also the icon for central control /changeover stays on both all the time..wired remotes are brand new on the install..
4.i have tested ..and the unit turns on and works in cooling when i heat the room the termostats..now i am just stuck with it..i cant make it heat..

Sorry for the first long post and i hope some one can help..
I havent found. Anyone that turned a cooling only to heating and i cant ask for help..maybe i can help others in future if i figure out why isnt changing over..
Thanks..

[nike123]

And you will never make it heat!

[Stefce]

Why wouldnt it heat?

[hyperion]

You would have been much better off buying an RXYQ5 unit and cutting your losses.

[Stefce]

Well i ordered a replacement pcb for around 400$ and it works..heats and all..i guess i can copy the eprom from the new pcb and compare it or just copy over the eprom of the old pcb and have both pcb's heat..
Daikin did its homework and thought how to make money on parts also..since they knew somebody would think to add a eev to the daikin and a 4 way valve and make it heat..but no..they went a step ahead and disabled heating in the eprom..and cooling only can be selected on the ds1-3 dipswitch..if its up..but no..they had to make sure somebody spent more money to make it heat...

[Brian_UK]

Well of course they did, do you really think that manufacturers are going to give away their technology for nothing.

Have you now calculated your total expenditure of buying a cooling only unit, an EEV, a 4 way valve, a new PCB and labour. How much cheaper was it than buying a ready made heat pump?

[Stefce]

Total cost around 600 or 700$.. if u consider labour
Unit price was 600$..with 2 wall mounted units and 2 wall remotes.. so 1300$ for the total value