410 vs 454b refrigerant
anonymoususer
| Posted in Mechanicals on
hi, mechanical professionals ! I notice that neither mitsubishi nor fujitsu (both are common brands in my community) offers a “cold climate” heat pump compressor that allows any refrigerant other than 410A. I understand the epa is phasing this chemical out. I want to buy equipment but am holding off till 454b-friendly compressors become available in case I ever needed refrigerant added or swapped out in future. What are other people doing who need heat pumps now: holding off or waiting ? Any clue when mitsubishi or fujitsu will start offering 454b friendly compressors ? Thanks
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I am waiting. I plan on installing a number of smaller single units for greatest efficiency and turn down for low loads. Not really wanting to hear an HVAC tech look at me and tell me that I really should switch to 454B equipment because I am still on the "getting more expensive and scarcer" legacy refrigerant (410A). I know there are hundreds of thousands if not millions of the units using the old refrigerant and that there will need to be a replacement for them...I just don't want to be part of that group.
Additionally....the lessening of the environmental impact with the new refrigerants if you believe the numbers are a crazy reduction.
Our heating contractor has pushed the dates back a few times for the availability on the new refrigerant units…they are now saying Fall of 2025 but who knows.
I am far from an expert....but for my two cents....I'm gonna wait for Mitsubishi....which seem to be taking......a ................reallly.......................long.....................................time.
Best of luck with your project.
THank you. A local hvac contractor states that his supply house is finally offering some 454B equipment from Mitsubishi. I believe Samsung heat pumps are also widely available using this. Like you, I am going with multiple small (half ton) single zone ductless systems cuz I hear too much bad about multizone. The visual detriment of having multiple compressors outdoors is not an issue. I thought I could save by opting for one multizone four-ton with 8 indoor heads vs eight half-ton single zone systems. I got bids from several installers and so far the cost difference has been less than $1000. Good luck to you as well !
Have you seen the NEEP tool for heat pump sizing? It's a little tricky to use and you need to follow the steps to get the benefit out of it. First enter your parameter information to get a list of heat pumps. Then you click on the specific heat pump (Use the Advanced System Sizing button and toggle the View back and forth between Classic and Basic) and use that to generate a graph (at the very bottom) that shows given your room load and outdoor temp what percentage of the time you will be short cycling, unable to meet load, modulating, etc. It's incredibly useful for imagining your use case and sizing your heat pump. I have attached a screenshot of a room I have with a 10K load using a 6K MUZ-FSOGNA***...if you know the heat pump you're going to be using I think you can enter it directly on the Selection Page. Anyway you need to spend time with it to make the data meaningful...or at least I did. In general you want your results to have a long green line like the graph included here with minimal short cycling and close attention to where the unit won't be able to meet the load. This is the link: https://ashp.neep.org/#!/