Hoshi 502 to 22 .... Can Do or NOT?

[R12rules]

I got a Hoshi 600 # remote. The TX is bad. It's an old R502 system.

Billi-Bob just did a unit replacement for them.
He made sure and used lots of Ductape! Oh, and he let his two best clamp on Watsco line tap valves jus for good measure! :p

(ya gotta love the small town atmosphere) :D


Anyway, since I have to cut this sucker open anyway, I thought I would get the charge changed to something the newer models ran on for awhile.

Has anyone converted a 502 Hoshi to 22 and been sucessful?

Gosh I hope that guy didnt install a new unit filled with 404!
That may be what's fudging up the TX valve.

Sorry Dice, I didnt mean to attract you here by using the keyword: "fudge".

[a\c don]

I have converted some 502 systems to 22 with no prob.
Changed txv, oil, evacuate, recharge and go.

[a\c don]

Originally posted by a\c don
I have converted some 502 systems to 22 with no prob.
Changed txv, oil, evacuate, recharge and go.

Not familiar with Hoshie

[condenseddave]

It can be done, but you need Hoshizaki's valves, of which, Hoshizaki will never tell you the tonnage.

Best bet is to drop in 408.

[icemeister]

Back around '93 Hoshizaki switched over to R22 for a while before finally going with R404A later on. The R22 systems had cap tube liquid injection as an attempt to keep the discharge temperatures from going through the roof, which always appeared to me to be a good example of 11th hour enginneering that allowed them to sell machines but compromised the system reliability. R22 was not a good refrigerant for these machine IMHO.

Stick with R408A or R402A (HP80) and you'll have no problems. I've got a couple of Hoshi 1200 R502 remotes running on HP80 (and no oil change) for 7-8 years with no problems. I haven't seen any old R22 machines lately. ;)

[gdavis]

Whats wrong with putting HP-81 in the machine? Its what we do and it works excellent.

[icemeister]

HP81 will work but it's really a specialty refrigerant for Manitowoc B-machines and not necessary for a Hoshizaki. The lower discharge temperatures you get with R408A or R402A will help extend the life of the compressor as well.

[condenseddave]

Originally posted by gdavis
Whats wrong with putting HP-81 in the machine? Its what we do and it works excellent.

You can buy 502 for a few dollars more than 81., why bother retrofitting??????????/

[gdavis]

Hey I dont have a clue as to how much some of this mess I use costs. If it aint broke I dont care about it. I dont get involved in the financial end of it. Someone asks me how much something costs and I give them the office phone number and who to talk to.

[R12rules]

Originally posted by gdavis
Hey I dont have a clue as to how much some of this mess I use costs. If it aint broke I dont care about it. I dont get involved in the financial end of it. Someone asks me how much something costs and I give them the office phone number and who to talk to.

The policy setters are both service tech as well as bean counter.

If a guy has been around a long time, like Icemeister or Dave, they know it both ways & inside out. That's how they are able to decipher which would be the best repair method.

This does not make the lowly service tech a bad dude, it just means he is more than likely going to be told what to do, rather than being able to determine the best course of action .... all on his lonesome.

And there is absolutley nothing wrong with that method. We have all lived with it for many years.

However, for a service company to have a man who is both familiar with that they are doing .... as well as the money aspect ... that person will definately be the most valuable employee over the long haul.


There is a Bible verse, it says; "Study to show yourself approved".
In our context, this would mean we should learn all we can of the "how's" as well as the "why's" of this service oriented industry.

[r404a]

R12-

Icemeister beat me to the punch. Ditto what he said about 402A. I worked for a Hoshizaki distributor in the 90's and remember when they switched over.