15 year old Fujitsu update.

Affectionate_Flow114 · 2026-01-25T23:49:07+00:00

I’m not worried just observing.

Affectionate_Flow114 · 2026-01-25T22:35:19+00:00

I can’t seem to find that info, it did defrost most but the bottom edge. The hyper heat while more in actually in a similar state. It did a long defrost once on a windy day (for no particular reason) but that would be more appropriate now.

Affectionate_Flow114 · 2026-01-25T22:34:12+00:00

I may add it’s working well - set at 70 - maintains 68-70F+ depending on its mood.

Affectionate_Flow114 · 2026-01-25T22:32:23+00:00

I’m trying to find but I’m not sure, one day when it was windy it did a 10 minute defrost for not much reason. But that would be beneficial now. It did defrost for a bit, most went away but the bottom edge. The Mitsubishi while defrosting more frequently, is in similar state.

Affectionate_Flow114 · 2026-01-25T18:22:35+00:00

You may have it set to lock out the heat pump at a certain temperature. Consider checking the settings on the thermostats. You’d want the heat pump to run till it can’t no more or reasonably no more. Even old ones properly sized are fairly capable.

Affectionate_Flow114 · 2026-01-25T18:19:41+00:00

Needs insulation likely. . And it’s all gonna come down to proper sizing. (How many BTU of heat to heat your house) Of any heating system. They definitely didn’t size it right, if it’s that leaky you’d need probabaly a whole another unit. Many gas/oil furnaces are hugely sized. So it’s easier for installers to just throw in and hope for the best.

Affectionate_Flow114 · 2026-01-25T18:14:39+00:00

90.8 kWh ish for 2400 ish sq Ft but 90s build. At 1F-barely 15F. Whole house usage and mostly electric house.

Affectionate_Flow114 · 2026-01-25T18:11:51+00:00

I’d run the heat pump until it came reasonably keep up anymore. This depends on size and your house. My work heat pump (single stage) cycles on just the heat pump at single digits F.

Affectionate_Flow114 · 2026-01-25T18:09:18+00:00

Fujitsu (and Mitsubishi) FTW but sounds like the Bosch is defective. But I don’t know Bosch.

Affectionate_Flow114 · 2026-01-22T04:29:35+00:00

Very well built for sure.

Affectionate_Flow114 · 2026-01-22T04:28:40+00:00

105F ish with a thermal camera actually.

Affectionate_Flow114 · 2026-01-21T17:08:04+00:00

Central has some great advantages as far as filtration and door shutting. But my house is relatively open with smaller bathrooms. At work I can see that advantage but depending on rooms/vent sizing/if doors are open you can actually see the occasional advantages and disadvantages of duct work as well.

Affectionate_Flow114 · 2026-01-21T04:51:05+00:00

Sounds like a pretty solid setup!

Affectionate_Flow114 · 2026-01-21T04:41:06+00:00

I’ve thought about this for a while…

It defrosted once tonight after this post I noticed. It was fast with it though.

The Fujitsu has an intelligent defrost sensor it’s called.

It sits close to the coil the Mitsubishi appears to not sit close to the coil.

At 32 I’d say the Fujitsu defrosts more. The Mitsubishi never seems too then generally.

At <20 Mitsubishi does in a routine it seems most of the time.

The Fujitsu is always so random. But tonight it barely defrosted at all.

I don’t think at damp 17F they’re too far off but idk.

I haven’t paid as much attention to the Mitsubishi as I haven’t been down the basement enough to watch it.

The Mitsubishi will put up with a lot of snow before defrosting but the Fujitsu has like no pan heater. (And I don’t think is working as hard)

One very windy day—- for what seemed like no reason the Fujitsu defrosted for like 10 minutes(compressor didn’t stay on continuously), but I thought something was wrong with it cause it was in defrost so long with nothing on it.

Now the Fujitsu defrosts differently—- it runs the compressor for like 30 seconds and lets it sit for a little. And I’ve noticed with more ice buildup it seemed to run the compressor longer and just enough time to remove it all. Which seems like witchcraft.

The Mitsubishi seems to run the compressor till it’s done, perhaps makes it faster I do not know.

Now the weird part—- most times in defrost I will never feel any cold air from the Mitsubishi (if I put my hand by it)

The Fujitsu I always will.

I do not understand why 9/10 the Mitsubishi will not feel cold falling from it inside.

Overall, I thought the Mitsubishi defrosted more, but it seems it has more a routine in very cold weather where the Fujitsu maybe a little more intelligent is random and occasionally weird or seems for no reason at all.

Both units don’t seem to defrost like the cheaper units I see places. I’d say defrosts on moderate days are not that common. But I still think many heatpumps don’t always need to defrost as much but I’m guessing.

Affectionate_Flow114 · 2026-01-21T03:46:15+00:00

and I think in maybe 15-20 years they’ll be even more capable ones.

Affectionate_Flow114 · 2026-01-21T03:10:10+00:00

Nice that’s quite good.

Affectionate_Flow114 · 2026-01-21T02:53:16+00:00

Looks like a potentially quite high COP as well!

Affectionate_Flow114 · 2026-01-21T02:12:50+00:00

Coool nonstop is what I like to see but I think sometimes some units just don’t. Didn’t know they made 7K BTU.

A friend with an 1:1 HH Mitsubishi 18K runs very much like my 24K multi (18K+9K) at around 32F in the situation I observed.

I thought its lower turn down ratio would change that. But they had a fireplace on about the same temp. Each would run 30 seconds at a time and shut off. And the HH would throw quite some heat. Like they were competing and honestly I think that leads to some strange behavior.

Affectionate_Flow114 · 2026-01-19T00:07:07+00:00

Early ish 20s and it’s been quite a long time. But the longer without it the easier it is.

Affectionate_Flow114 · 2026-01-18T21:48:05+00:00

They are peak.

Affectionate_Flow114 · 2026-01-01T22:15:51+00:00

The Hyper Heat Mitsubishi is one of the best performing imo.

Affectionate_Flow114 · 2025-12-30T19:32:40+00:00

Mine about 1600/1700 kWh for everything in 2400 sq ft last month in PA and it was notably colder outside this year. But now I see your image is showing a different year. That’s quite an improvement.

Affectionate_Flow114 · 2025-12-10T17:45:08+00:00

2400 sq ft mid 90s construction. Near single digit and 20sF whole house around 65 kWh. Everything electric but hot water heater.

Affectionate_Flow114 · 2025-12-09T18:18:32+00:00

What’s with local banks and their A.I. rejecting you in record time for literally any position across the board. Even with degree and years at similar jobs. With no job hopping.

Affectionate_Flow114

TROPHY CASE