Bosch Heat Pump Experience?

[EbS-P]

Supports my thoughts. Bosch is not top tier equipment but probably a good value. https://hvac-talk.com/vbb/threads/2242876-Bosch-Heat-Pump-Or-other?p=26282861#post26282861

Good advice…

Bosch vs American Standard

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[stoveliker]

Reading that thread I see more differences in contractor working habits than a legitimate comparison of two brands (in particular since the two offers are for qualitatively different systems).

I would not be able to conclude from that thread that Bosch is worse than A.S.

 

[EbS-P]

Reading that thread I see more differences in contractor working habits than a legitimate comparison of two brands (in particular since the two offers are for qualitatively different systems).

I would not be able to conclude from that thread that Bosch is worse than A.S.

my take was Bosh is not a Mitsubishi inverter and that’s drops it down to an equivalent price point of an AS two stage system.

Installer matters a lot probably more than brand. Ask for a Load calc and don’t use anyone who says it’s not necessary.

 

[peakbagger]

I think I qualified myself pretty well in my original post that this was directed to people who are in cold climates that routinely go under 20 F. I spent about 2 years carefully keeping a eye on my minisplit versus wood boiler and due to my unusual house setup I could do both as for 8 to 10 hours a day I would be in my office heated with the woodboiler with the main floor heated with a minisplit (main floor is less than 1000 square feet. My electric power is essentially free so it came down to comfort and my observations were that the minisplit gave out reasonable heat down to 20 F but anything lower and it was compromise especially if it was precipitating outside which led to more frequent defrosts. If it was col dry and sunny I could get down to 15 F but it was brderline. I live with sub 20 F nights for 3 to 4 months a year and seasonal lows can get down to -20 Fand in years past - 30 F was not unknown. The funny thing is, the ASHRAE design temps for the locality nearby is around -15 F but when I worked in the local plant we routinely experienced -30 F for a couple of stretches almost every year in late January early February. That is where I got familiar with poorly designed steam coil air preheaters that would literally freeze and split despite live steam being in the top header.

So if you live on an island or along the New England coast feel free to go all electric with mini splits but dont try to take your experiences in a relatively temperate climate and transfer to a truly cold climate.

 

[stoveliker]

Well, that is your experience. Mine was different - and whether this is for 24 hrs.or for 3 months doesn't change how the system works.

I also gave a few pointers as to how to avoid a bunch of the complaints you had.

I certainly agree these things are not the best in every situation.

 

[Prof]

I am currently heating my 2400 sq ft house with wood (Buck 91)/oil/heat pump (Trane). To offset the cost of oil and use less wood this year I have dropped the crossover outdoor temp of my heat pump to 20 degrees. Its keeping up for most part down to these temps but have hear Bosch Inverter Duct Split (IDS) can run down to 5 degrees effectively. Has anyone ran this model down to these temps or lower than 20 degrees?

Debating on replacing my heat pump for Bosch that claims to function in lower temps in hopes to offset the cost of oil....but don't want to waste my $$$$!

Thank you!

I have a Bosch heat pump. I have it set so the emergency heat typically kicks in at 15F. We had a cold week last year, so I dropped it down to 10F to see what would happen. It was in the teens and the Bosch didn't have a problem keeping my house at 68F. I still mostly use wood when things get cold, but the Bosch has exceeded my expectations. The inverter is great and keeps the unit working at the most efficient level. The cooling ability has really impressed me. Whole house AC in the summer, keeping my house at 68-70 only costs an extra $20. One window unit would raise my bill by that much in the past.

 

[stoveliker]

Back to Bosch, I wonder if spare parts may be an issue? (See e.g. European car maintenance in the US?)

 

[EbS-P]

Back to Bosch, I wonder if spare parts may be an issue? (See e.g. European car maintenance in the US?)

Even the made in the USA brands have had parts availability issues. Biggest killer of these inverter systems is voltage fluctuations. Really need whole house surge and a voltage monitor on the system.

 

[Brian26]

The Gree Flexx is the only true whole house ducted unit I know of using an enhanced vapor injection compressor. These blow away the old top discharge american units. These were exclusively found on mini siplits up until recently and offer huge boosts in efficiency and severe cold capacity. The Gree Flexx is also a side discharge and has a basepan heater and the same sophisticated defrost controls as a mini split. Not some dumb timer. They use sophisticated software to monitor coil temps, and the outdoor fan load to only defrost when absolute necessary.

General Electric just started selling the Gree Flexx as a rebadged unit called GE Connect. On another forum I visit a ton of these Gree/GE Connects are being installed in really cold parts of Canada because of their good extreme cold weather performance. The same Gree is also being rebadged by other brands in Canada. Some areas of Canada have some absurdly generous rebates and with carbon taxes these are being installed like crazy.

I'll try and find the post but some guy in I think Alberta put all kinds of crazy sensors on his GE Connect to monitor liquid and suction line temps, return air/supply, electricity consumption, cfm, etc. He was trying to automate it to get a real time COP number. He posted some data with his unit running at -33c (-27 f) and it was still putting out like 75% of its capacity at a COP of like 1.5. I believe the Flexx is rated to 79% capacity at -22.

The Mr Cool universal is also a rebadged Gree Flexx. That unit is also avaliable with the DIY quick connect fittings that requires no refrigerant work.

 

[EbS-P]

The Gree Flexx is the only true whole house ducted unit I know of using an enhanced vapor injection compressor. These blow away the old top discharge american units. These were exclusively found on mini siplits up until recently and offer huge boosts in efficiency and severe cold capacity. The Gree Flexx is also a side discharge and has a basepan heater and the same sophisticated defrost controls as a mini split. Not some dumb timer. They use sophisticated software to monitor coil temps, and the outdoor fan load to only defrost when absolute necessary.

General Electric just started selling the Gree Flexx as a rebadged unit called GE Connect. On another forum I visit a ton of these Gree/GE Connects are being installed in really cold parts of Canada because of their good extreme cold weather performance. The same Gree is also being rebadged by other brands in Canada. Some areas of Canada have some absurdly generous rebates and with carbon taxes these are being installed like crazy.

I'll try and find the post but some guy in I think Alberta put all kinds of crazy sensors on his GE Connect to monitor liquid and suction line temps, return air/supply, electricity consumption, cfm, etc. He was trying to automate it to get a real time COP number. He posted some data with his unit running at -33c (-27 f) and it was still putting out like 75% of its capacity at a COP of like 1.5. I believe the Flexx is rated to 79% capacity at -22.

The Mr Cool universal is also a rebadged Gree Flexx. That unit is also avaliable with the DIY quick connect fittings that requires no refrigerant work.

I’ve been watch hvac channels on YouTube. This gentleman is in the south somewhere. If free flex is good enough for a professional….. it’s probably worth looking into.

Edit.. floors are not insulated so how far south is that????

 

[EbS-P]

I’ve been watch hvac channels on YouTube. This gentleman is in the south somewhere. If free flex is good enough for a professional….. it’s probably worth looking into.

Edit.. floors are not insulated so how far south is that????

Looked up the data for a 5 ton unit. 26k btus (50% rated capacity about) and 1.3x COP at -22F. I’d probably install strips in a cold climate. I wonder if you can run strips and compressor at the same time? 10kw strips would be my choice.

ASHP

ashp.neep.org

 

[stoveliker]

In Knoxville, I had a (there) standard ducted HVAC system for heat and cooling. I hated the strips that kicked in when the heat pump did not perform below 40 F. When I replaced the system (old, breaking down), instead of the strips I put a gas burner in for when it was cold. Way faster heat and (then) way lower cost than resistive heat.

If one puts in strips, why not have the electric baseboard heating - same technical efficiency (100%, as all resistive heat), but less (duct) losses, and more amenable to only heating a few rooms because closing off vent registers messes with the balance and leakage of a ducted system.

 

[Prof]

Looked up the data for a 5 ton unit. 26k btus (50% rated capacity about) and 1.3x COP at -22F. I’d probably install strips in a cold climate. I wonder if you can run strips and compressor at the same time? 10kw strips would be my choice.

ASHP

ashp.neep.org

The strips will not run at the same time as the heatpump on my unit. I agree in a cold climate, I'd install strips. If the heatpump fails for any reason, I can still use the strips (i.e., emergency heat).

 

[EbS-P]

In Knoxville, I had a (there) standard ducted HVAC system for heat and cooling. I hated the strips that kicked in when the heat pump did not perform below 40 F. When I replaced the system (old, breaking down), instead of the strips I put a gas burner in for when it was cold. Way faster heat and (then) way lower cost than resistive heat.

If one puts in strips, why not have the electric baseboard heating - same technical efficiency (100%, as all resistive heat), but less (duct) losses, and more amenable to only heating a few rooms because closing off vent registers messes with the balance and leakage of a ducted system.

Ease of installation. Pull one set of conductors. Strips are cheap. And install in 10 minutes. What you save with a heatpump you can just burn some of that savings to run the strips. With the variable speed equipment you size for heating. Strips make it more comfortable during defrost and add capacity when you are below design temp. Yea you have duct losses. Encapsulate your crawl space and don’t run ducts in attics.

Installers need to ask more questions when setting up a unit. Or a thermostat needs to have a comfort $$$, normal and penny pincher settings. Strips should not come on at 40 degrees. Loot at the temperature performance data and choose the the temps when they come on.

The strips will not run at the same time as the heatpump on my unit. I agree in a cold climate, I'd install strips. If the heatpump fails for any reason, I can still use the strips (i.e., emergency heat).

I wonder if a safety or a setting only one at a time.

 

[Highbeam]

The Gree Flexx is the only true whole house ducted unit I know of using an enhanced vapor injection compressor. These blow away the old top discharge american units. These were exclusively found on mini siplits up until recently and offer huge boosts in efficiency and severe cold capacity. The Gree Flexx is also a side discharge and has a basepan heater and the same sophisticated defrost controls as a mini split. Not some dumb timer. They use sophisticated software to monitor coil temps, and the outdoor fan load to only defrost when absolute necessary.

General Electric just started selling the Gree Flexx as a rebadged unit called GE Connect. On another forum I visit a ton of these Gree/GE Connects are being installed in really cold parts of Canada because of their good extreme cold weather performance. The same Gree is also being rebadged by other brands in Canada. Some areas of Canada have some absurdly generous rebates and with carbon taxes these are being installed like crazy.

I'll try and find the post but some guy in I think Alberta put all kinds of crazy sensors on his GE Connect to monitor liquid and suction line temps, return air/supply, electricity consumption, cfm, etc. He was trying to automate it to get a real time COP number. He posted some data with his unit running at -33c (-27 f) and it was still putting out like 75% of its capacity at a COP of like 1.5. I believe the Flexx is rated to 79% capacity at -22.

The Mr Cool universal is also a rebadged Gree Flexx. That unit is also avaliable with the DIY quick connect fittings that requires no refrigerant work.

And it's cheap! If not for the PITA of installing ductwork (heavy permitting and physical challenges), I would be running a MRCool universal. I predict that it (and other rebadged versions) has made everything else obsolete.

 

[begreen]

Back to Bosch, I wonder if spare parts may be an issue? (See e.g. European car maintenance in the US?)

That's a reasonable concern. We have a made in Germany Bosch vacuum for which they stopped selling and removed all Bosch vacuum support in the country about 4 yrs after we bought it. This was not a cheap vac. On the other hand, we have a Bosch dishwasher that has been great. It was made in North Carolina, so support is more likely to be sustained.
Still, unless the cost savings was really major I think I would go with Mitsubishi or Daikin for their good track record and well-established network.

 

[EbS-P]

And it's cheap! If not for the PITA of installing ductwork (heavy permitting and physical challenges), I would be running a MRCool universal. I predict that it (and other rebadged versions) has made everything else obsolete.

I’m not sure I would go that far. But a it is a competitor that higher priced brands have to take note. Not sure it will increase quality but probably more reduce price. At the end of the day lack installing or changing filters probably kills more units that poor quality control.

 

[maple1]

Just a quick general comment on mini-split comfort.

I have found that floor mount units are noticeably more comfortable than the standard wall mounts when heating. For same size btu ratings. I plan to put one more in our place next year, it will be a 15 or 18k cold climate floor mount. There is a cost premium. But worth it.

 

[EbS-P]

Just a quick general comment on mini-split comfort.

I have found that floor mount units are noticeably more comfortable than the standard wall mounts when heating. For same size btu ratings. I plan to put one more in our place next year, it will be a 15 or 18k cold climate floor mount. There is a cost premium. But worth it.

How about cooling. High wall units make more sense from convective loop perspective. Floor units coils might get dirtier faster.

 

[stoveliker]

Mine can blow from near the ceiling where they are mounted to the floor 2.5 ft in front of the wall. You can feel it with your feet when walking: nice warm floor.

So that is what I do when heating. I think that is very close to having one mounted at floor level

I've seen many minisplit heads that don't blow as steep down.

 

[maple1]

How about cooling. High wall units make more sense from convective loop perspective. Floor units coils might get dirtier faster.

Works fine for cooling.

 

[maple1]

Mine can blow from near the ceiling where they are mounted to the floor 2.5 ft in front of the wall. You can feel it with your feet when walking: nice warm floor.

So that is what I do when heating. I think that is very close to having one mounted at floor level

I've seen many minisplit heads that don't blow as steep down.

Don't think that's quite the same effect as warm air blowing straight across the floor.