ccjersey - 4/25/2024 10:09

If the connection sizes are the same then you’re ahead of the game.

Condensers are designed to start out with parallel paths for the vapor and then as the vapor condenses, they combine into a single outlet tube. So hooking them up in series is probably going to just reduce the liquid temp and dramatically increase the refrigerant charge required more than it’ll reduce the head pressure. Most of the volume of a condenser is full of vapor and only the bottom of it has liquid that’s being hopefully being sub-cooled. Hooking up the second one in series, you’ll have a lot more volume for subcooling………LOTS more volume!

Ideally you would connect them in parallel to have more room for hot vapor (lower head pressure) but to have the same “several paths that combine into one” construction. There’s such a thing as too low head pressure. We don’t normally experience it because the designers of the systems don’t let it happen. If the compressor doesn’t make the vapor hot (temp and pressure are directly related) then on a hot day, there may not be enough difference between condenser and air flowing over it to get heat to transfer as well. If heat doesn’t transfer out in the condenser, the system doesn’t remove heat from the cab.

You want there to be a supply of reasonably cool liquid refrigerant available at the expansion valve at all times. Bubbles are not a good thing there.

I wouldn’t bother doubling up unless you use an add-on condenser designed for that purpose or hook the two normal condensers in parallel.