anyone got any affordable hydronic fan coil recommendations

BTW, just to be the first commentor on my own thread ;- ), some of the cost on these fan coils is wrapped up in control and my best experience has been with dumb units where i control delivery temp of water and maybe manual flow adjustment and maybe manual adjustment of fan speed to obtain balanced comfort under constant circulation. so my ideal fan coil would not have a zone valve or complicated fan operation controls.

@Big Ed_4 I presume by OEM you mean a unit complete with case and controls and condensate management for non-concealed mounting.

I get that I could box a coil myself to make a simple fan coil and save vs the sometimes extravagant pricing for an off the shelf package, but the DX units most often present with a finished wall or ceiling unit (or an air handler with condensate collection and plenum/duct fittings comparable to capacity). But if you aren't parsimonious you can pay as much for a stand alone hydronic fan coil as for an entire DX system. That just doesn't feel right to me, but maybe it is a question of the market being constrained to commercial and tower scale residential that either don't move the number of units that the residential market does or maybe just are more elastic as to capital investment so margins are not as constrained by pricing pressures.

if i was only thinking about heating i'd be less focused on a package product. maybe this is a technology at a chicken and egg point. Everyone is going DX and while refrigerants and refrigerant piping are an achilles heal there, the hydronic alternative with extra heat exchanging stage has its own complications keeping air to water heat pump sales low comparatively and then the costs of anti-burst fluid management and insulated lines. My experience with chillers suggests to me that over the long haul such systems will last longer but not sure the payback is there. Open to comments on whether my affection for hydronics is just comfort with what I believe in and in advocating for chiller style heat pumps which have failed to take root, I'm like the marxists going on about how no-one has done communism right instead of just giving up and going DX which is where the capitalists are headed at the moment.

my biases admitted, I wonder if the lack of hydronic fan coil penetration in the residential market to date is a negative thing. yeah, you had to run 120 for the units but you didn't need the wall space and a lot of times it would be easier and less expensive to get ODR capable emitter plan without going full radiant. i guess the residential version that follows on residentail AC boom is really coils in the air handler although air handlers need . . . ducts. so even with attention to continuous insulation I prefer to run pipes to ducts. yet another bias :- ).

when i first began servicing a residential complex with these units in the early 1970s where, ironically, these space age looking units were employed so as not to cover the historic baseboards with hydronics and to provide the option for central air, i'll admit that keeping up with filters and fans alone– nevermind longer arc maintenance of zone valves and controls–made be long for the passive emitters I was more familiar with. But of course those could not function for cooling (albeit condensate collection introduces more cleaning and maintenance). And, over the course of maintaining that same building until we sold it last year I became impressed with the ability of the units to adapt to ODR compared to traditional residential hydronic emitters. And I solved the zone valve problem by getting rid of them and just going to constant circulation with ODR control. There was even enough passive capability in these units given that they tended to be tall enough to effect modest thermal air circulation that tenants often didn't run the fans especially on the sunny side of the building. (everyone ran the fans in AC season).

traditionally the zone valves were actuated by return air temp sensed at the unit with constant running of fans. with no remote sensing, i.e. distant room thermostat, beyond the onboard zone valve balancing units was handled just by tenants switching the fan speed-which they mostly set it and forget it unless they experienced discomfort. balancing valves would be a handy first order but where the load varies depending on sunlight or other factors I would have run room thermostat wire when these were installed to control the fans, or maybe a proportioning valve but that seems like more of maintenance headache than multi or variable speed fans.

I know some manufacturers are providing wireless thermostat controls that i imagine provide some of this functionality but nothing like a wire if you can plan during reno for its routing. I'm not insistent on massively intellgient algorithms, I ran these units 50 years with no zone valves and manual fan control and the only complaints I ever got was when the domestic hot water had priority and folks would be taking a shower but that cut into the feed temps for the fan coils (solved that by getting the DHW separated onto on demand takagi and the mod cons ran cooler, condensed more. i don't like combined systems whether indirect tank or within the appliance. I was handling 10 showers with a 199,000 btu takagi without complaint–partly due to the more stochastic nature of usage than in the old 9-5 realm. only EPA could screw up something perfectly good like that by trying to get rid of non-condensing on demands. the condensing units work fine and save a little extra but my experience is the service life is in the mid single digits vs decades for non-condensing. from life cycle point of view, what makes sense isn't even close unless you need the venting convenience of the condensing. but I digress).

For conditioning larger spaces with larger individual units (maybe 30,000 btu/hr?) at some point you might get some payback from sophisticated control of variable speed fan motors but even the rudimentary constant circ ODR system I backed into was pretty damn satisfactory.

And while the filters and cleaning the squirrel cages, etc. remain a PIA, that can have an independent contribution to indoor air quality. OF course probably some particulates is good for us since habituation to too clean ain't necessarily the best balance; but, while I didn't do air quality testing, the stuff I saw changing filters and cleaning fans suggested to me that there would have been some useful benefit although not sure how much of this was sustained in the air from the circulation itself. comments?

these units were Trane, e.g. B22A00xU style. they long ago gave up supporting them but the motors were universal enough and the filters likewise such that I was able to maintain them and they were working just fine almost 60 years after install. Trane tried for that space age, look ma no screws, so taking the covers off was more difficult than necessay and the fan mounts that used partial physical sheet metal interlock and partially screws could have been better from a serviceman's point of view but was robust enough that didn't need repair even 60 years in. Trane came up with better quality drip trays from the original styrofoam although they stopped offering them before I had replaced all of ours. should have had the vision to buy them all ahead. and i replaced the coin vents with 1/8 inch ball vales and elbows but all in all I give the units decent marks. I feel like there must be something equivalent out there under a grand. Am I dreaming?

@jumper that is good thinking but doesn't it strike you as odd that we have to got through that. I would think there would be more of a market for modest fan coils with finish trim. but that's me.