repourposing a 410a MiniSplit condensing unit

[JMG1951]

repurposing a 410a MiniSplit condensing unit

just when I think I've heard it all...

Today a client asked me to look at a brand new Mitsubishi MUZ-a09 outdoor condensing unit. Brand spanking new in the box.

He wants to know if I can use it to remote a three door cooler he has in his bar. Too much noise and heat being put out by the top mounted R22 3/4hp Copeland (which is uber-old and well past its retirement)

I'm hesitant because I've never seen it done, but it seems I could replace the R22 TXV and set the appropriate thermistor temps.

Ideas???

 

[Milton Shaw]

What is the BTU rating of the present compressor/cooling setup. I would think that pressures would be too high for existing evaporator and lines. You should be able to get a remote refrigeration unit that would do a better job. Sort of like grocery stores use for all their coolers. Pressures would be way off from R22 to R410 systems and BTU differences would make the system freeze or not cool, either one with a lot of food it it would be a problem.

 

[Jackfre]

I would be way more than shy of trying to fool the electronics of the Mitsu. Given they are modulating they are all the time looking at internal coil temp, room temp, outdoor fan speed and compressor speed. Sounds like a no win job from a lot of perspectives.

 

[JMG1951]

yeah, I was concerned jumping from 250 to 400psi!

the thermistors are easy enough to fool but the Inverter controls are going to take so long to work around that any savings he might see with a 'free' condensing unit would be eaten up PLUS heaven help the next tech to see that Frankenstein.

 

[Jackfre]

Also, if you feel pressured to do this and go forward with it you will OWN that thing, and it you. As soon as this guy pays you ten bucks on this he will expect success. It is remarkable how customers have a convenient lapse in memory when they push their way and it goes sideways. I have seen so many situations where you try to satisfy a customer and it ends up costing you the account. As a businessman, the best thing is to stand up for your customers interests as well as your own and tell him he is throwing good money after bad. You are the pro. Research the proper method of handling this and be prepared with pricing and provide the options, proper options that is.

 

[JMG1951]

boy howdy brother, we've all had good intentions come back to bite us in the ****.

In his defense though, it was an interesting question that I had never considered.

He has access to 31 of these condensers and I wanted to throw the idea around...

 

[LS6 Tommy]

I'd politely decline and offer to relocate the existing condenser outside. Mini split outdoor units don't work the same as regular split refrigeration systems and you can't use an R22 line set or evaporator with 410a. Even if you could, due to the difference in load range, it won't work (well). IMO, you will end up losing a client.

Tommy

 

[eddieK]

I would be way more than shy of trying to fool the electronics of the Mitsu. Given they are modulating they are all the time looking at internal coil temp, room temp, outdoor fan speed and compressor speed. Sounds like a no win job from a lot of perspectives.

Yep - Communicating equipment.

In the early days I did use the simple mini split condensing units with conventional systems, all that was needed was installing a contactor. Those days are long past.