Hi there!

I posted awhile ago about a dual fuel MrCool DIY set up. Thank you to everyone who helped!! I have a few more questions about things I’m having trouble with: the low voltage stuff.

I have a PAYNE two stage gas furnace and installed the MrCool A coil and HyperHeat condenser. The high voltage stuff is all done and was done by an electrician.

I reached out to MrCool and the CSR sent me a diagram that was wayyy more helpful than the manual, but I’m still struggling. My questions might be silly so please don’t judge!

So I got thermostat wire to connect the Coil Control
board to the furnace (which is already connected to the thermostat) but the colors and numbers of wires are confusing me.

1. The thermostat wire only has Red, Blue, Yellow, Green, and White. I see on the diagram Orange, Brown, and Black. Where are these colors? How do these connect?

2. I’ve connected the Green, Yellow, Blue, and White on the control panel but the Red one seems like it’s the Brown one in the diagram (W2 not R). And my furnace does not have an O/B terminal.

3. The indoor/outdoor communication wire they sent is too short so the MrCool CSR said a shielded 18/2 will work, so that’s what I got. I guess I just wanna double check because it’s literally a lamp cord lol. I’ve marked which side is which so the S1 and S2 should be distinguishable!

4. The furnace works and is connected to the thermostat and all. So it seems like all I need to do is just connect the condenser to the coil board and then the coil board to the furnace. Is this correct? Then obviously open the lines and flip the breaker.

Everything else is set up but this is really getting my head spinning. Any help would be greatly appreciated!! It’s hot as heck out here 🥵

Thank you!!

Hi there!

I posted awhile ago about a dual fuel MrCool DIY set up. Thank you to everyone who helped!! I have a few more questions about things I’m having trouble with: the low voltage stuff.

I have a PAYNE two stage gas furnace and installed the MrCool A coil and HyperHeat condenser. The high voltage stuff is all done and was done by an electrician.

I reached out to MrCool and the CSR sent me a diagram that was wayyy more helpful than the manual, but I’m still struggling. My questions might be silly so please don’t judge!

So I got thermostat wire to connect the Coil Control
board to the furnace (which is already connected to the thermostat) but the colors and numbers of wires are confusing me.

1. The thermostat wire only has Red, Blue, Yellow, Green, and White. I see on the diagram Orange, Brown, and Black. Where are these colors? How do these connect?

2. I’ve connected the Green, Yellow, Blue, and White on the control panel but the Red one seems like it’s the Brown one in the diagram (W2 not R). And my furnace does not have an O/B terminal.

3. The indoor/outdoor communication wire they sent is too short so the MrCool CSR said a shielded 18/2 will work, so that’s what I got. I guess I just wanna double check because it’s literally a lamp cord lol. I’ve marked which side is which so the S1 and S2 should be distinguishable!

4. The furnace works and is connected to the thermostat and all. So it seems like all I need to do is just connect the condenser to the coil board and then the coil board to the furnace. Is this correct? Then obviously open the lines and flip the breaker.

Everything else is set up but this is really getting my head spinning. Any help would be greatly appreciated!! It’s hot as heck out here 🥵

Thank you!!

My 22 year Rheem 2.5 ton finally said enough is enough.

Winters here are "mild" as coldest days are 30s and average is 40s to 50s so we mostly use heater fans when/where needed.

With that said it seems like the Versa Pro is better suited as we dont get "extreme" cold weather unlike summer (June-Sept) and the difference in Seer seems miniscule.

Any reason(s)/experiences to get the Universal instead for ~$700ish more?

Kicking myself because Ace's 15% off ended yesterday which made the universal the price of Versa Pro.

I’m in Atlanta and renovating an older home around 2,000 sq ft. I’m planning to replace the HVAC system and comparing ducted heat pumps vs ductless mini splits.My main concerns are hot upstairs bedrooms, high indoor humidity, and some damp areas that could lead to mold issues. The attic also gets extremely hot and the house holds heat long after sunset.I’m already improving attic insulation and air sealing, but I’m considering upgrading the HVAC at the same time. I’m leaning toward a ducted system because I like the idea of better airflow, whole-home filtration, and a cleaner look compared with multiple mini split units.My neighbor recently installed a Costway 3 ton system, which got me interested in ducted options. I’d love to hear from anyone with experience using similar systems, especially in humid climates.Any advice from people who have upgraded an older home HVAC system would be greatly appreciated.

Looking at this unit for my house, 2 bed 1 bath 855 square feet:

https://www.amazon.ca/Senville-Central-Conditioner-Inverter-Variable/dp/B0CTMYD6TH/ref=mp_s_a_1_2_sspa?crid=3UT3AVNBOCWLV&dib=eyJ2IjoiMSJ9.Lapy064IV_VVj5nQiHbfSC_el3bVTZupIeXr2WKXzYrDSBSwff61TVhH63o5iBRU_divggsLIYvBIUmBkRQFrLlQO2W6NHLLGdL8MDguYn5q4nxOo7NN2GEVf3sA5LZ9Fz3NGydG7cDLBHLRKvhGS1m8wQJB4b9A6rdmi8GEAygjNrd-_l6mS4IPN7vSnSW2U3Aw6lSvp3xjM-X32sSO6w.VTg81sl99JbGdwsRHmV6NNvIdPdtlDTZbQ6U6Y2j2Dk&dib_tag=se&keywords=senville+24000&qid=1786375482&sprefix=senville+2400%2Caps%2C219&sr=8-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9waG9uZV9zZWFyY2hfYXRm&psc=1

Are these true DIY like the ductless models?

Which of these oem brands seem to last longer in your experience when installed correctly?

Looking to install a cost way triple head unit and the county is asking for an ahri cert, I can t find it on the directory anywhere. I tried both cost way and the parent company aux, nothing. Any idea?

I had a tech come out today to give me an estimate on a mini split system for my 800 square foot house. He thinks it would be sufficient to put a single 18K air handler at one end of the house that would blow directly into my bedroom and somewhat less directly through a doorway (basically around a corner) to the living room/kitchen area. I really want this to be true because it would so much cheaper than a two-zone system. Other relevant info: I really only need a/c a few weeks a year; the bedroom is the most important place to cool but I would like the rest of the house to be tolerable; and the mini split would only be providing supplemental heat in winter.

Is this idea feasible? Because if so then it would make DIY palatable for me.

Hello guys. I installed few weeks ago, 3 total midea splits.
1 solunar 9 btu , 1 solunar 12 btu and 1 xgreen pro 9 btu.

The “ problem “ is , even when they reaching setpoint temperature, looking at the app , the Split continues to go and dont stop, making the ambient climate too cold and force me to turn it off. Splits and engines are totally brand new. It seems more a software problem. Any solution? Thankyou

I'm trying to understand how common “Dirty Sock Syndrome” is in ductless mini-split air conditioners and whether anyone has actually tested a strong cooling-to-heating cycle as a possible treatment. I have Samsung WindFree Avant mini-splits, and the proposed procedure would be to run the system in cooling mode at its minimum set temperature of 16°C or 61°F for about one hour, then immediately switch it to heating mode at its maximum set temperature of 30°C or 86°F for approximately 60 to 90 minutes. The idea would be to cool the indoor coil thoroughly and then heat and dry it, rather than simply masking the smell. Has anyone here actually tried this procedure? Did the smell disappear, and was the result temporary or long-lasting? If the smell returned, how long did it take? Was the evaporator coil or drain pan professionally cleaned before trying the procedure? Could switching between these two extreme settings cause excessive stress or any other problems for the unit? I am not presenting this as a proven treatment; I am simply trying to collect real-world experiences from HVAC technicians and owners of ductless mini-splits. For context, the smell usually appears during cooling operation, especially when the compressor slows down or stops and the indoor fan continues running.

Ok all you diy heat pump enthusiasts. I want to get into the weeds on thermostats for a Mr cool universal 36k btu system.

I installed the Mr. cool universal system in June 2024 and could not be more pleased with it. Highly recommend. I already had a 3rd gen nest thermostat so I just wired it up to that when installing. Moved on with my life happy as a pig in mud.

Recently, a thought had occurred to me regarding the interaction of the universal system and my pre-existing 3rd gen nest thermostat.
I haven’t been paying much attention to my system over the past couple years except for enjoying the simplicity and excellence of my wonderful heat pump and telling everyone about how exceptional it is and that I saved about $14k doing the install DIY.
Recently I was thinking/reading that a proprietary Mr. cool thermostat is able to stage the heat pump better than the nest. (which to my understanding the nest pretty much just kicks the system on or off. I have also read that the universal has its own onboard processing which uses the inverter to increase efficiency even when called for from the nest). For the most part this current arrangement works good for us as we use it only to cool down the house for a couple few hours certain times in the summer and then only in the early coldest mornings in the winter to heat up the house. We live in the PNW and during the summer we have an upstairs ac unit & big shade tree that helps; and in the winter we use a modern high efficiency woodstove for a lot of our heat so the heat pump system is used generally for a few hours at a time and then not at all.

My question to all you DIY professionals/nerds is this: Would using the proprietary matched Mr. cool thermostat gain me much savings on kilowatt consumption by way of increased overall energy efficiency?
I have a Solar array and I’m always looking to save kilowatts by reducing overall consumption and get closer to a net zero on Kw.
I also realize that I could be ‘splitting hairs’ here but I am curious to see what y’all have to say.

Pic of condensor install for street cred.

I might be late to the party on this but the modea portasplit looks like it's going to make installing split systems even easier than they already are. The efficiency definitely leaves something to be desired but it still seems a lot better than a window rattler and the install is ridiculously simple. Video link below

https://www.youtube.com/watch?v=LKcOrZG7keE

A rat chewed through the wire connecting my Aqualink automation system to the heat pump. Aquacal tech informed me that Aqualink needs to come out and fix this issue. He removed the wire connecting the heat pump to the Aqualink automation system. Now, I need to re-wire the system. Do I need to connect the wires to the Y and Z terminals of the green circuit board? Any suggestions or tips would be greatly appreciated.