Anyone have experience with Mr. Cool heat pumps?

[yeti]

I'm going back and forth on whether or not to go all in on electric -- solar panels, heat pump, and electric water heater -- and ditch natural gas altogether. The problem I'm having with HVAC is that the Mr. Cool heat pump that I'd like to install (MDUO1836) only appears to be capable of upflow or horizontal orientation for the air handler while I need downflow. Does anyone have any experience with this model or type of air handler? I asked to question to Mr. Cool customer service but didn't receive any response. I'd like to be able to install myself and have had good luck with Mr. Cool mini-splits.

[yachi]

I'm going back and forth on whether or not to go all in on electric -- solar panels, heat pump, and electric water heater -- and ditch natural gas altogether. The problem I'm having with HVAC is that the Mr. Cool heat pump that I'd like to install (MDUO1836) only appears to be capable of upflow or horizontal orientation for the air handler while I need downflow. Does anyone have any experience with this model or type of air handler? I asked to question to Mr. Cool customer service but didn't receive any response. I'd like to be able to install myself and have had good luck with Mr. Cool mini-splits.

Are you sure you don't mean MDUI18036?  I see that more on a google search.  The installation manual for it says: "The return ductwork is to be introduced into the air handler bottom (upflow configuration)"

If you're asking "should I install this model in an orientation inconsistent with the manufacturer's recommendations" I'll give you a hearty heck no.  Everything from how the driptray functions, to how well the components are protected from moisture, to how efficiently and silently the blower runs could be affected.

When we first moved in to our house, we had a split system with natural gas fed heat.  The air handler or ductwork had an issue whereby the air flow was turbulent where it discharged into the main duct at the top of the unit.  The airflow was so odd, that it suspended the droplets that condensed out of the airstream, and leaked where it wasn't supposed to - missing the driptray and corroding the natural gas components.  I'm not sure how often the previous owners used the system, but we replaced it as it was 30 years old when we moved in.

[yeti]

Thanks for the response. Yes that's the same unit, I just used the model number off the Mr. Cool website

I understand that there are issues with moisture and changing direction of the drain pan, but in theory there shouldn't be a difference in swapping the fan and heat exchanger and reversing the fan direction (physically being able to do this is another story) -- other brands of AHU do allow this and even some Mr. Cool products do from what I've seen. I'm not suggesting that I would go buy one and hack it up -- I was just wondering if anyone else had experience with this model. Perhaps no DIY downflow heat pump solution exists.

[yachi]

Thanks for the response. Yes that's the same unit, I just used the model number off the Mr. Cool website

I understand that there are issues with moisture and changing direction of the drain pan, but in theory there shouldn't be a difference in swapping the fan and heat exchanger and reversing the fan direction (physically being able to do this is another story) -- other brands of AHU do allow this and even some Mr. Cool products do from what I've seen. I'm not suggesting that I would go buy one and hack it up -- I was just wondering if anyone else had experience with this model. Perhaps no DIY downflow heat pump solution exists.

It's best to find a model that works for downflow, or modify your ductwork to make it work.  I'd be hesitant about changing the direction of the airflow through the unit.  When a manufacturer does this, they then subject the unit to testing to make sure the airflow is still laminar through the unit, and water doesn't pool in weird places.  Given enough motivation, I think you could do something and have it work at least 5 years, but if you're getting a bit of moisture on a critical component, it might not make it 15 years.

[uniwelder]

What do you mean when you say you need down flow?  What's the current configuration of ducting?  Is your natural gas unit in the attic with a main return in the ceiling and a network of ducts to the various rooms?

[yeti]

It's best to find a model that works for downflow, or modify your ductwork to make it work.  I'd be hesitant about changing the direction of the airflow through the unit.  When a manufacturer does this, they then subject the unit to testing to make sure the airflow is still laminar through the unit, and water doesn't pool in weird places.  Given enough motivation, I think you could do something and have it work at least 5 years, but if you're getting a bit of moisture on a critical component, it might not make it 15 years.

I wish I could find a downflow model that works with their precharged linesets, but I'm not aware of any. The modifications I could do would be to build a duct to reverse the flow either from upflow or horizontal. I guess I could see certain things that could affect the airflow, but as long as the fan and heat exchanger are oriented the same and the return and supply duct conections are the same size there shouldn't be much difference.

[yeti]

What do you mean when you say you need down flow?  What's the current configuration of ducting?  Is your natural gas unit in the attic with a main return in the ceiling and a network of ducts to the various rooms?

My current configuration is the ducts are built into the foundation (slab on grade) so there's no modifications that can be done there. The furnace is in the garage and blows down into the ducts which also connect to the swamp cooler outside (would have to be blocked off if I install a heat pump). The air return is a single vent that goes through the garage wall into the furnace, near the ceiling obviously.

[Ripple4]

I'm going back and forth on whether or not to go all in on electric -- solar panels, heat pump, and electric water heater -- and ditch natural gas altogether. The problem I'm having with HVAC is that the Mr. Cool heat pump that I'd like to install (MDUO1836) only appears to be capable of upflow or horizontal orientation for the air handler while I need downflow. Does anyone have any experience with this model or type of air handler? I asked to question to Mr. Cool customer service but didn't receive any response. I'd like to be able to install myself and have had good luck with Mr. Cool mini-splits.

If the furnace is in the garage maybe the horizonal layout could work just build a workbench over it and have a 90deg duct shoot into the floor? alternately keep the furnace you have, put a ECM blower in and a good filter and install a few minisplits in the most used rooms then the air will move around and get filtered via the old furance. I like that Mr.cool 3kbtu deal and I also like the no-NG idea. there is youtube where a guy put in one and it only cost him ~$3xx more over the year to heat and cool, in a northen climate no less. but he saved ~8K on the DIY install.

[yachi]

Thanks for the response. Yes that's the same unit, I just used the model number off the Mr. Cool website

I understand that there are issues with moisture and changing direction of the drain pan, but in theory there shouldn't be a difference in swapping the fan and heat exchanger and reversing the fan direction (physically being able to do this is another story) -- other brands of AHU do allow this and even some Mr. Cool products do from what I've seen. I'm not suggesting that I would go buy one and hack it up -- I was just wondering if anyone else had experience with this model. Perhaps no DIY downflow heat pump solution exists.

They make a conversion kit for some other models.  You can see what it consists of here: https://www.homedepot.com/p/MRCOOL-Signature-Air-Handler-3-5-Ton-Down-Flow-Kit-MSHDK3660/314412475

Insulated drain pan
Insulated downflow coil support brackets
Insulated inner drain pan drip shields
Non-insulated outer coil slab shields
Front and rear insulated air seal plates
Tapping screws and some insulated foam tape

Insulated stuff because the drip pan water is going to be cold - you don't want air condensing on the underside of the drip pan and dripping on the blower.

You could contact MrCool and see what they would suggest instead.  See if they're considering a conversion kit for this one.

[sonofsven]

I don't have any experience with Mr. Cool; however, the pool heater I just installed has detailed instructions to change the orientation by re-arranging the internals. Have you downloaded the installation guide and read it?
Also, contact the company, and always follow the recommended install or you will void the warranty if you have problems.

[index]

Get the Midea version which allows for down flow and vacuum the linset.

https://www.minisplitwarehouse.com/product/midea-24000-btu-20-seer-central-ducted-split-hyper-heat-pump-ac

If you have installed a few mr cool diy units, you are plenty capable of commissioning the unit.  You will need a few hundred dollars worth of tools which you can resell or use again later:

$100 Vacuum pump, $130 micron Guage, $35 vacuum rated hose, $50 core removal tool, $30 blank off valve.

I would by the core tools and micron guage on ebay and you should be able to recover 80% of the cost.