Heto freezer

[dennis korah]

Hi, i am facing a problem with "HETO - FRREZER" Cascade system Low side compressor charged with R-170 Ethane Gas, please let me know any other replacement gas is suitable for this Freezer.

[srikanth_5430]

Respected Engineers,

please give me information for heto freezer (UF5420) and circuit diagram and trouble shooting.

[norseman]

Hi to both with a Heto problem.

May be you know, but the thing is that Heto is not out in the market anymore. The Danish producer was bought up together with the French Jouan by Thermo scientific later merged to Thermo Fisher.
This huge company just let the both drop dead and that was proably due to make less competition.

R170 return oil very easily due to it is a hydrocarbon type. The oil separator is a pretty weak type too so if you try some other stuff, you can end up with a restricted capillary tube. It should be quite easy to get hand on R170. I have testet R508B on similar systems and added R290 propan up to 1abs. pressure before charge for the oil return and it worked. Very expensive the 508B and proably not easier to get hands on + you have to get some R290.
R23 create very high discharge temperature so I would not tried that one out.

Manuals and schematic can you get if lucky by contacting Thermo Fisher, but I think they do not stack a room full of them and the interest in serving Heto problems is probably at a zero level, but who knows? May be some Danish refrigeration guy see you request and help you out. The biggest market was in Denmark. They made them the last year or two in Slovakia I believe.