Tk v200max 20

[aircon50]

Hi all

Above unit on a 2004 Transit, approx 6 cu m, with frozen spec insulation (eg freezer side door).
Has been running chilled but client now requires it for frozen. First things first, recover refrigerant, replace drier, and recharge with virgin R404a.

SP - Suct Press (psig). ST - Suct Temp at steel fitting to SPR valve. DP - Disch Press (psig)
RA - Return Air measured with Fluke 77 (Cº). CC - Cab control Temp (Cº)
Running on standby for constant compressor speed.
Time Amb SP ST DP RA CC Notes
15:30 23 18 1.4 270 -11.5 -11
15:45 23 17 1.5 265 -13.0 -13
16:00 24 14 1.8 250 -14.0 -14
16:15 24 13 -0.3 250 -15.3 -15 Suction frosting
16:30 25 13 0.2 250 -16.3 -16 - " -
16:45 25 11 0.6 240 -16.4 -16 - " -
17:00 24 11 -1.1 240 -16.4 -16 - " - heavily
Run through manual defrost and close TXV 1/2 turn.
17:15 23 16 5.0 260 -12.7 -11
17:30 22 13 4.3 240 -15.6 -15
17:45 21 11 2.6 230 -17.8 -16
18:00 21 10 1.5 225 -18.5 -18 Light frost on suction fitting
Comments please!

Another question - is it possible to convert a V090 from R134a to R404a? Apart from the HP and LP switches, will it require the installation of a liquid inj valve?
Thanks in advance
Graham

[charlie patt]

was your 200 originally on 134 or 404, you wont need liquid injection but you will need to change to 32 grade oil if running coninued freezer and connect drain line heaters they are not always there also alter your df term temp and sea if it has a thermistor on body of comp

[aircon50]

Hi Charlie
Thanks for your reply. As the title suggests, the V200 as a MAX was originally on R404a, and on a freezer spec van. I was hoping someone would peruse the figures. I still feel the TXV could close down a little more.
The conversion question was regarding a V090, which was only supplied by TK on R134a. I was looking to help the client by giving a bit more capacity.
By the way - seeing as you are in Devon - do we know each other? My business was Reefercare back in the early 90's, and worked very closely with Ken at Roadfridge (whom, I see, are still going strong!).
Graham

[charlie patt]

sorry i should have seen the max bit, as regard to capacity of unit its either the tev wants a tweak or the orifice is restricted, and of course i no ken but john runs it now, as far as the 134 unit pressure switches mop tev oil change but your ambient is warmer so thats not a must and adjust df parameters and dl heater if it aint a big van it will do it ok