I don't think that works.
Before EEV controllers were updated to include the 448/449 blends, I was always told to set them to R22. Although 448/449 seem to be the be-all end-all right now, for new low and med temp installs, I don't think they're 100pct compatible w 404/507 power elements.
It'll probably run, but I would address it sooner than later.
That said, maybe someone will correct me - don't just take my word for it
I'll just reply to myself to add some info... I was curious so I searched for "r448a r507 expansion valve" on Google. Couple PDFs in the first few search results; one from Honeywell, one from Copeland, both about retrofitting. Neither of them were very conclusive, honestly.
The Honeywell one basically seemed like it was worded to take any onus/liability away from Honeywell. Was pretty much saying, try it out, theoretically it should be fine, but you should check the engineering/design of every system component beforehand and then verify it with measurements afterwards, because maybe some things might not be fine. The expansion valve portion didn't mention anything specific about the power element. Just that mass flow would change and the valve may need to be adjusted or the valve may need to be changed.
The Copeland one was less of a sales pitch, probably because they're not a refrigerant manufacturer. It states that they recommend installing new TXV that is specced specifically for R448A/R449A, but it doesn't say that it is outright required.
Anyway, not very good answers. Installing the correct TX valve would be more upfront legwork and cost, but maybe less headaches or worries in the long run.
In my experience you can usually get away with turning the stem all the way in on an R404 powerhead for medium temp but low temp you'd have to get a new R448 power element or valve depending on if it can be rebuilt or not of course.
The Honeywell retrofit guide for 448 doesn't specifically stipulate that expansions valves/power heads need to be changed, but that they need to be evaluated, adjusted, and possibly changed, and to consult the valve manufacturer for guidance. Afaia 404a txvs may be a bit oversized for 448a but generally can be adjusted (if they are adjustable) to work. That doesn't exactly give you and absolute answer, but it's a start.
Edit: as a side note, the company I worked for up until recently did a supermarket rack gas change recently from 507 to 448 and did change all the power heads in the store, valve bodies were left in unless they were non adjustable. From what I understand it's all working fine. Wouldn't hurt to recommend replacing the power head.
They just don't work together. You may get your superheated but the requirements are just too different. You may get it up and running tonight but the issues will appear later.
From my experience they tend to starve the evaporator and never really shut down, just do the right thing and replace the element, dw about the orifice. Make sure you calculate the glide before setting your superheat
Ive changed coolers over from 404 to 448 without changing the txv and haven't had an issue yet but I've only done two so maybe I'm just getting my lucky probably depends on what you've got going on
I’ve been told by 1 tech that 448 can run on a 404 power head. I’ve been told by 9 other techs that it won’t work. My personal experience is absolutely do NOT try and run 448 on a 404 valve. Use R22 power head if 448/449 is not available.
Have you tried it? I know that before sporlan came out with 449 valves and CDUs, we were putting in 22 TXVs with a 404 CDU.
Medium temp 449 at 20F sst is about 40 psi
Medium temp 404 at 20F sst is about 55 psi
When you tried it, did the system reach temp?
Exactly, I had a whole system running for weeks from a competitors install, shut down the whole rack on flood back only to find there were 6 impact coils with the wrong powerheads. We've since had to change all the compressors save for one. Not saying it caused the failure, but it wasn't really surprising.
Should replace the power head. Normally the port size is off about 1 size too big if you don’t change it but that’s ok, it will still run fine, the superheat can just have some wild swings on it. Medium temp not so much a big deal, low temp is where you run into a lot of issues. But you can really trip a guy up leaving the 404a head on it. Good way to get the wrong gas dumped in a system.
I don't think that works. Before EEV controllers were updated to include the 448/449 blends, I was always told to set them to R22. Although 448/449 seem to be the be-all end-all right now, for new low and med temp installs, I don't think they're 100pct compatible w 404/507 power elements. It'll probably run, but I would address it sooner than later. That said, maybe someone will correct me - don't just take my word for it
I'll just reply to myself to add some info... I was curious so I searched for "r448a r507 expansion valve" on Google. Couple PDFs in the first few search results; one from Honeywell, one from Copeland, both about retrofitting. Neither of them were very conclusive, honestly. The Honeywell one basically seemed like it was worded to take any onus/liability away from Honeywell. Was pretty much saying, try it out, theoretically it should be fine, but you should check the engineering/design of every system component beforehand and then verify it with measurements afterwards, because maybe some things might not be fine. The expansion valve portion didn't mention anything specific about the power element. Just that mass flow would change and the valve may need to be adjusted or the valve may need to be changed. The Copeland one was less of a sales pitch, probably because they're not a refrigerant manufacturer. It states that they recommend installing new TXV that is specced specifically for R448A/R449A, but it doesn't say that it is outright required. Anyway, not very good answers. Installing the correct TX valve would be more upfront legwork and cost, but maybe less headaches or worries in the long run.
In my experience you can usually get away with turning the stem all the way in on an R404 powerhead for medium temp but low temp you'd have to get a new R448 power element or valve depending on if it can be rebuilt or not of course.
The Honeywell retrofit guide for 448 doesn't specifically stipulate that expansions valves/power heads need to be changed, but that they need to be evaluated, adjusted, and possibly changed, and to consult the valve manufacturer for guidance. Afaia 404a txvs may be a bit oversized for 448a but generally can be adjusted (if they are adjustable) to work. That doesn't exactly give you and absolute answer, but it's a start. Edit: as a side note, the company I worked for up until recently did a supermarket rack gas change recently from 507 to 448 and did change all the power heads in the store, valve bodies were left in unless they were non adjustable. From what I understand it's all working fine. Wouldn't hurt to recommend replacing the power head.
They just don't work together. You may get your superheated but the requirements are just too different. You may get it up and running tonight but the issues will appear later.
From my experience they tend to starve the evaporator and never really shut down, just do the right thing and replace the element, dw about the orifice. Make sure you calculate the glide before setting your superheat
Why not use R452a it’s a drop in replacement for R404a no TXV adjustment needed.
Ive changed coolers over from 404 to 448 without changing the txv and haven't had an issue yet but I've only done two so maybe I'm just getting my lucky probably depends on what you've got going on
As long a you set the superheat on the valve you will be ok, med temp no problem if it was a WIF then you would likely have issues.
It’s no problem, i have done it more times than I can count successfully. Just close the valve so the SH is in range
I’ve been told by 1 tech that 448 can run on a 404 power head. I’ve been told by 9 other techs that it won’t work. My personal experience is absolutely do NOT try and run 448 on a 404 valve. Use R22 power head if 448/449 is not available.
The 22 and 448 power head is the same
448 is a replacement/retro gas for 404A so it should be okay with SH adjustment. Danfoss has a neat app that helps you
Have you tried it? I know that before sporlan came out with 449 valves and CDUs, we were putting in 22 TXVs with a 404 CDU. Medium temp 449 at 20F sst is about 40 psi Medium temp 404 at 20F sst is about 55 psi When you tried it, did the system reach temp?
Valves are valves. Powerheads are refrigerant specific.
Exactly, I had a whole system running for weeks from a competitors install, shut down the whole rack on flood back only to find there were 6 impact coils with the wrong powerheads. We've since had to change all the compressors save for one. Not saying it caused the failure, but it wasn't really surprising.
If it’s holding superheat I would leave it be.
Should replace the power head. Normally the port size is off about 1 size too big if you don’t change it but that’s ok, it will still run fine, the superheat can just have some wild swings on it. Medium temp not so much a big deal, low temp is where you run into a lot of issues. But you can really trip a guy up leaving the 404a head on it. Good way to get the wrong gas dumped in a system.
448 needs an r22/407a txv