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Mitsubsihi Electric PUHZ-P200

June 15, 2015, 1:09 pm
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We have an application where there's a PHE installed between compressor and outdoor coil. The PHE is fed with brine of 12°C.
The outdoor is installed in the cellar (indoor) because there was no possibility to install the unit outdoor.
We extract heat in winter for heating and release heat to the brine in summer.
So a second heat exchanger in serial with the standard aircoil.
I realise this is no a common setup;

We have following thermistors 0n the outdoor
TH3: liquid (outlet condensor)
TH4: Discharge
TH6: Second face pipe (halfway condenser) What' the purpose of this sensor.
TH7: Outdoor

Does somebody know what the logic is for determining the speed of the compressor? What ramps up or down the compressor?
What the logic is or determining the speed of the condenser fans?
What the logic is for determining the opening of the EEV?
We now have strange phenomenas where the EEV closes for a TE of - 25°C while in cooling mode and an indoor of almost 30°C.
Is the unit trying to maintain an always fix superheat of +/- 4K?
In heating mode, unit is working perfect.
We only have problems in cooling mode (P6 error = liquid pîpe temperature is lower than -15°C) because te EEV regulates for -25°C. (brine 12C and indoor temperature is 28°C) So superheat is +/- 50K.
When we stop brine flow through PHE (it then becomes very hot in the cellar of course because we're then condensing on the outdoor coil only) then the compressor ramps up and we have a TE of +10°C for an indoor of 30°C.
Obviously, the cooling rate of the brine is too big for condensing. We're somehow overcondensing and the thermistor and/or the software are seeing this as an error.

manual page 13 http://www.mitsubi****ech.co.uk/Data...CH424revD).pdf
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Ecodan installation around Reading assistance required

June 16, 2015, 1:53 am
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Customer of ours is having a new build and the designer has spec'ed a 14kw ecodan. we are not approved for these so will need to pass it over

If anyone is interested please let me know asap.

Richard
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not pumping down

June 16, 2015, 10:24 am
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Looking at a cold store today customer said it not stopping when door switch activated the switch is a basic switch that could be used for lighting etc,this switch energizes the liquid line mag valve,checked no power at valve attached gauges suction pressure high 65psi closed receiver valve ,no difference closed suction valve no difference? Asked customer if temperature log shows any warm readings no all seems to be right the compressor is a maneurop mtz 64 back to the compressor again closed valves again all works fine? I suspect the compressor is faulty as the customer said it did not stop when entry switch was used yesterday,any ideas has this happened to anyone in the past
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WRV 163 issue? never seen this before (video)

June 16, 2015, 2:25 pm
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A WRV 163 unit I encountered a while back, been lazy and only uploaded the video now.

I did the alignment, left it with the motor 0.05mm higher than the compressor (was told some time 15 years ago that compressors in the WRV range lifts 0.05 mm when they start running, so rule of thumb is to leave the motor higher, don't know if it's true), sideways and angular was 0.03.

The first pipe is the discharge pipe, the second pipe, towards the end is the start/stop unloading pipe between the oil separator and suction

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Sanyo controller fault indication

June 17, 2015, 4:32 am
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Hi I am trying to establish what the problem is which a Sanyo controller RCS-TM80BG is indicating. There is a small flashing triangle with an exclamation mark in it. I understand from some info I have downloaded that this refers to 'protective device activated' but that is all I can find. Does anyone know what this means and where I can find more info on it?

Thanks in advance
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Ambguity in Refrigeration tonnage of Chiller

June 17, 2015, 10:50 am
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My model is YPC-ST-400 meaning its TonsOfRefrigeration (TR) is 400
As can be seen we have total refrigerant (water) amount of 550kg



Using steam tables at (~5celsius) saturated properties of water:

Code:
SATURATED
Sat. pressure            0.8718 kPa ~6.5mmHg
Sat. temperature        5.0000 C
Quality                  1.0000
Moisture                0.0000
Enthalpy
  hf                    21.0067 kJ/kg
  hfg                2489.7275 kJ/kg
  hg                  2510.7342 kJ/kg
Internal energy
  uf                    21.0058 kJ/kg
  ufg                2361.4265 kJ/kg
  ug                  2382.4323 kJ/kg
Entropy
  sf                    0.0762 kJ/kg/C
  sfg                    8.9507 kJ/kg/C
  sg                    9.0269 kJ/kg/C
Specific volume
  vf                    0.0010 m3/kg
  vfg                  147.1621 m3/kg
  vg                  147.1631 m3/kg
Thus at evaporator per kg water being evaporated @6.5mmHg will remove ~2489.7275kJ
of enthalpy from the chilled water. Assuming that ~60% of 550kg water is continously
circulated to evaporator we can calculate max. amount of enthalpy that is being
removed & then translate it to TR ...1TR=~3.5kW ...1kJ/sec=1kW

TR = 2489.7275kJ/kg x (550x0.6)kg/hr x 1hr/3600sec x 1TR/3.5kW = 65.2TR

Even if I had 100% water circulation to evaporator which is nonsense I cannot get the value 400TR?
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Daikin pcb

June 17, 2015, 10:58 am
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Can anyone help we have 2 ftxs 25 wall mounted units on a multi of 2mxs 50 only 6 months old a board was faulty on one indoor unit we change the board over and we are getting a code of u4 which is comication but now we have a problem the other unit does not work now we reset the power
This is strange
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Tk ts 200

June 17, 2015, 11:40 am
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got a code 68 up internal controller ? Any assistance gents never had this one before ta charlie
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Charging

June 19, 2015, 4:04 am
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Hi All I was wondering if you guys could please clear up question for me & my friend.
We are both new to the refrigeration trade so are both learning & doubting are selfs some times we are both being told different things by engineers & having a debate on which is correct..

My friend came to & told me he was charging a walk in freezer with 404a but was not getting any of the running pressure that he should have been I've been told by superior for a freezer back pressure of 1bar & head just above 200 psi in not sure what my friend has been told but he was getting no where near these pressure & was told when it's a long pipe run just ignore the pressure & fill to the sight glass basically only use the gauges to check for blockages.. My stand is that you go off sight glass & running pressure not just sight.. I'd have thought it does not matter on the size of the system cause you accomadate for that by adding extra refrigerant..

Please some one clear this up!?
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Flea market: International Journal of Refrigeration on sale

June 19, 2015, 8:32 am
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Ten full years of the International Journal of Refrigeration, complete and in perfect shape. Journal reserved to IIF/IIR members, not sold in public. Academic and university research in the field of refrigeration, air conditioning and heat pumps. Retail value of 75 Euro per issue. Collection of over 80 issues. Over 5000 Euro value! Only pickup, the weight is over 50Kgs. Contact me if you are abroad or overseas.

http://www.ebay.it/itm/121680721151?...84.m1555.l2649
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Opinions on Freezer Room condition

June 19, 2015, 2:11 pm
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Recently got a service call to a large Freezer Room. The complaint was that the room took longer than expected to reach set point (-20*) after room was turned off for cleaning.
Readings for the last 5 days seem okay apart from the day in question.
The evaporator has had a history of partial freezing and had the txv and orifice replaced within the last month.
Today I checked the evaporator to find the partial freezing had returned.....the room was at -18.5*.
Evaporator coils were ice free as was the expansion valve, the ice formed on bottom left surface on the fins.

Anyway I'm wondering what you think of the condition of the system from the readings I took. Condensing Unit is on the building roof and the room has quite a large stock level but not overstocked.
R404a refrigerant
Ambient Temperature on roof 20*c
Saturation Temperature on gauge fitted to compressor suction port -30*c
Suction line temp at evaporator outlet -19*c
Temperature on gauge fitted to discharge port at compressor 34*c
Temperature of condenser outlet liquid line 17*
Air on condenser 17.5*
Air off condenser 19.5*
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Lennox LCH 803

June 20, 2015, 6:51 am
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Hello all
chiller Lennox LCH803
How to disable the operation of the compressor 1,2
Controller CLIMATIC 50
In the work leave the compressor 3
Thank you for your support
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No Low pressure liquid Pump

June 21, 2015, 3:47 am
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Hi

After having lot of problems with my cold store (leaking and highly inefficiency) I took charge of it and decided to replace old system/ upgrade with new ones. So I went for new condensers, addition of new evaporators and thicker insulations.

Also I planned to add new compressors of 290 KW instead of smaller 120 KW compressors I had to save electricity.


I was studying 2 diagrams of basic ammonia refrigeration and both shows presence of Low pressure liquid pumps which is just before low pressure liquid receiver.

http://www.rmtech.net/Copy_of_Refrigeration.jpg
http://www.coolpartners.dk/wp-conten...ystem-Full.jpg


The problem is that I do not have these pumps installed since last many years and I called some people in same industry and they also confirmed or heard of such pumps.

Can some one help me by solving this question that
1) What is function of this Low pressure liquid pump
2) Is it required in refrigeration where temperature is required at +3.0 Degree C

Our store is meant to store fresh fruits.

Your help would be really appreciated.

Regards
Salman Khan
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Converting Home Ac's to Centralized AC system with single compressor / condenssor

June 21, 2015, 11:52 am
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Hi

I am in Pakistan, temperature here in summers are 40.0 C ++ and I have at least 4 Ac's running all day long. Electric bills are high and so are maintenance costs.

I am planning to convert to 1 single compressor (400 volts) and 1 condenser (water + air based) to save electric cost and save maintenance.

For this purpose I am planning to install 4 evaporators separately each in one room with a carrier reefer container compressor.

http://www.carrier.com/container-ref...nits/ThinLINE/
http://www.containerequipment.nl/car...er-repair.html

This would be frequency drive such that frequency on compressor would be depending on number of evaporators working. For example for 1 evaporator 30 HZ, for 2, 40 HZ and for 4 50 Hz.... just an idea on frequency.

1) Do you think this would work?
2) Will this save electric cost?

Regards
Salman Khan
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Carlyle multiple reciprocating compressor systems/ low oil alarm in Carrier chiller

June 21, 2015, 3:25 pm
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Hello Dear Friends,
I have a refurbish carrier chiller type 30HT.
After I started up the chiller both systems A and B sounds an alarm 50 and 51 " Low oil pressure compressor A1 lead comp. in sys. A and B1 lead comp. in sys. B. (Note the compressors have oil equalizer pipe in each system).
I added a required oil to both systems and then less an hour all the oil in sys. A "four comp." and sys. B "three comp." disappeared completely.
Now I am confused !!
What happened and what should I do?
Even if one compressor in work also drag the oil from the rests.
Is it compressor's o-ring or vales problem?
I'm waiting your kind help my friends.
http://www.hosbv.com/data/specifications/3258%20-%20Carrier%2030%20HW%20052.pdf
Attached Images
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Ac compressor explosion

June 22, 2015, 6:50 am
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Hi
how r u
i got yesterday samsung mini split ac unit
with compressor exploded from terminal cover
exactly one of the terminal has blow up
my question
why a compressor blowup?
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DX Coil Control

June 22, 2015, 7:06 am
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Hell there, I have been asked to connect a Toshiba RAV-SM564ATP-E condenser unit to a DX coil mounted in a AHU. Am I right to assume that as the expansion device is in the condenser unit I need no further control at the coil?
Pipe sizes are 1/4" and 1/2"
The condenser is the same type you would fit on a split a/c system.
Many thanks in advance for any advice on this
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ex employee takes tools !

June 22, 2015, 12:27 pm
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Hi guys
we sacked a engineer the other day and he drove off in the van before we could sort out tools ,paperwork etc
we had to go pick the van up which was emptied ..
Short story is he diconnected the tracker then told us where it was but now he wants to be paid as normal even though we have no idea about his paperwork and the tools that have gone missing plus phone laptop uniform etc
anyone got any idea how we should deal with it?
The tools is annoying but we would let this go if he returned the other kit is phone etc
could we withhold final wages till he returns them ?

Thanks in advance
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inverter board

June 22, 2015, 12:27 pm
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Hello all,
I need help to know from where I can buy from UK an inverter board for a VRF unit PURY-P350 VGMA as this is out of stock in my country,an early reply is highly apreceated .
Regards
Kuti
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Daikin 3 pipe VRV Blocked pipe

June 24, 2015, 1:40 am
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Hi Guys,

Just like to run this by the Daikin experts out there. I was involved in a 3 pipe VRV install 2 years ago and i have received a service report from Daikin, stating that they had to replace a split reversing valve caused by a blockage in the equalizing line, their is a REYQ16PY, 12, and a 10 linked together. They have stated that this would not have been picked up during commissioning. I am of the opinion that it should have been picked up when the system was commissioned. Just for the record there was 3 other installers on site and one of them had left the stub closed on the equalising line and brazed the new pipe over the top. i have to reply to the builder this week so i thought i would get some input as to your thoughts on this. TIA
Kev
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