Results 1 to 13 of 13
  1. #1
    Join Date
    Oct 2014
    Location
    Braga
    Age
    26
    Posts
    3
    Rep Power
    0

    R290 as replacement of R404a



    Hi all!

    If I want to change the refrigerant (R404a to R290) of the equipment I need to do some changes like the compressor?



  2. #2
    Join Date
    Sep 2007
    Location
    Split Croatia
    Age
    51
    Posts
    6,100
    Blog Entries
    6
    Rep Power
    30

    Re: R290 as replacement of R404a

    Yes! Compressor Oil, expansion device etc... Depending on system.
    Now, when I am officialy citizen off EU, I am looking for decent job! For any job offer please check my profile!

  3. #3
    Join Date
    May 2012
    Location
    England
    Age
    53
    Posts
    1,234
    Rep Power
    28

    Re: R290 as replacement of R404a

    .

    I'd be more worried about the electrics.

    Some R290 systems I've seen use standard R404a compressors
    and TEV's but the electrics are different.

    Make sure all the electrics are either sealed or up or out of the way of
    any possible refrigerant leaks. All fan motors need to be constructed
    to a certain standard.

    EX rated motors
    (see http://www.hse.gov.uk/offshore/infosheets/is3-2010.htm for brief description).

    Fortunately most fridge motors are of an EX construction.

    Compressor starting and defrost control is the area that needs most attention.
    Anywhere on the system where a spark can take place (HP & LP switches) need
    to be sealed or removed up and out of the way.

    Regards

    Rob

    .
    Last edited by Rob White; 16-10-2014 at 08:36 AM.
    .. ... -. .----. - / -- --- .-. ... . / -.-. --- -.. . / --. --- --- -..

  4. #4
    Join Date
    May 2012
    Location
    England
    Age
    53
    Posts
    1,234
    Rep Power
    28

    Re: R290 as replacement of R404a

    .

    In the UK we don't recommend retro fitting an existing fridge to R290.

    It can be done but full risk assessments need to be taken beforehand.

    Rob

    .
    .. ... -. .----. - / -- --- .-. ... . / -.-. --- -.. . / --. --- --- -..

  5. #5
    Join Date
    Oct 2014
    Location
    Braga
    Age
    26
    Posts
    3
    Rep Power
    0

    Re: R290 as replacement of R404a

    Thanks guys,

    And what you think about performance? It will be better for same custs?

  6. #6
    Join Date
    May 2012
    Location
    England
    Age
    53
    Posts
    1,234
    Rep Power
    28

    Re: R290 as replacement of R404a

    Quote Originally Posted by tiagomartins007 View Post
    Thanks guys,

    And what you think about performance? It will be better for same custs?
    On paper it should be more efficient.

    In real life with all the variations that there are, you might
    find it to be no better or no worse.

    Rob

    .
    .. ... -. .----. - / -- --- .-. ... . / -.-. --- -.. . / --. --- --- -..

  7. #7
    Join Date
    Apr 2006
    Location
    Not so sunny coast (BC Canada)
    Age
    35
    Posts
    1,646
    Rep Power
    17

    Re: R290 as replacement of R404a

    I find on real world usages for air conditioning systems it proves to be much better in performance for cooling Vs electrical consumption., keeping in mind these are smaller systems.
    Now in Redvers Sask.

  8. #8
    Join Date
    Oct 2014
    Location
    Braga
    Age
    26
    Posts
    3
    Rep Power
    0

    Re: R290 as replacement of R404a

    And what about legislation?

    I read this
    "IEC 60335-2-24 and IEC 60335-2-89 currently restrict the charge size for commercial refrigerators
    and freezers and household refrigerators and freezers to 150 g of flammable refrigerant, respectively.
    This charge amount is considered to be safe if the appliance itself is tested for safety. The standard
    does not establish safety guidelines for units with a propane charge greater than 150 g"

    It meens it cannot be comercialized??

  9. #9
    Join Date
    May 2012
    Location
    England
    Age
    53
    Posts
    1,234
    Rep Power
    28

    Re: R290 as replacement of R404a

    .

    Your location says Braga. Braga in Portugal?
    You are European same as me and we use the same legislation.

    Depends on what you want it for.

    150 g is the limit for mobile and integral systems
    1.5 Kg is the limit in public areas (can go upto 5 Kg)
    2.5 Kg is the limit in commercial - private areas (can go upto 10 Kg)
    10 Kg is the limit for commercial - industrial areas (can go upto 25 Kg)
    No limit for a self contained packaged unit in a secure well ventilated area.

    This is a European directive so should be the same throughout Europe,
    but you will need to do training and research your local rules and regulations.

    Rob

    .
    Last edited by Rob White; 17-10-2014 at 01:32 PM.
    .. ... -. .----. - / -- --- .-. ... . / -.-. --- -.. . / --. --- --- -..

  10. #10
    Join Date
    Jun 2010
    Location
    Yorkshire
    Age
    52
    Posts
    504
    Rep Power
    12

    Re: R290 as replacement of R404a

    From what I remember when doing my first f gas certificate, the 2078, we just covered the storage and transportation of it, 3kg rings a bell when being used/stored in a room of 10 cubic meters. Only once ever come across it once and that was back in the early eighties on an old Carlisle water chiller centralised unit specifically made to run on lpg, that we decommissioned. Infact that was the first time that we ever used a recovery unit, that in turn was built by my boss out of canabalised parts, it took all day to fill 3x 30lb dumpies.

    And all the time being supervised by a clark of works that possesed no instruction or method statement, only ever asking us about our method of decommissioning then just simply agreeing with us and giving us permission to go ahead and refrain from smoking and using sources of ignition.

    Non of us could understand why this gas was being used, as we only ever come across r12 and r22 back in those days, and once came across a gas that was ether based, and we didn't know it had that inside until venting it. And it was me that found out it was ether as I ended up passing out whilst up the ladder. We just put it down that some boffins must have built it who knew about that kind of thing back then.

    I myself don't posses the lpg based licence but do however have the category on my gas safe card to work with it as a fuel. And I should imagine that low level ventilation would be a requirement when being used/stored inside a building? And as other posts state, the controls would have to be either intrinsically safe or class 2 flame proof category as a minimum, or standard controls located within a prescribed zone?
    50 hertz but 100s worse

  11. #11
    Join Date
    Feb 2010
    Location
    GREECE
    Age
    43
    Posts
    33
    Rep Power
    0

    Re: R290 as replacement of R404a

    Well ... why not go for the R407A??? instead?
    It will be a straight forward change with less hassle ...

    Now in case want for research... R290 requires changing the Condenser as well..

    For replacing the quantity of refrigerant... A very easy apply is that R290 will be the 1/3 of nominal R404A refrigerant supply. therefore Charge with 1/3 of the nominal capacity as the tech sticker suggest...

    Of course you may need to reduce or increase charging by grams...

  12. #12
    Join Date
    Feb 2015
    Location
    uk
    Posts
    34
    Rep Power
    0

    Re: R290 as replacement of R404a

    having had a lucky escape from a call out i went to were cowboys had filled a r134a system with r290 without telling anyone or even labeling the unit up as a flammable gas i would say stick with r404a as long as possible because when that stuff goes up it really goes up

  13. #13
    Join Date
    Dec 2007
    Location
    australia
    Posts
    2,459
    Rep Power
    27

    Re: R290 as replacement of R404a

    Quote Originally Posted by abp32 View Post
    having had a lucky escape from a call out i went to were cowboys had filled a r134a system with r290 without telling anyone or even labeling the unit up as a flammable gas i would say stick with r404a as long as possible because when that stuff goes up it really goes up
    Because of the "Cowboy" problem, we have a procedure & equipment to check systems before working on them, to check refrigerant is not propane etc.
    This is used on equipment we have not worked on or have history.
    You may only get one chance to check it or get it wrong, before accident happens.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •