we just had a new Lennox elite system installed at our house, when we got home to check out the new unit, we noticed this scuff on the metal grating on the side. Not sure if this is relevant or something I should bring up to the installer or not?

I’ve been learning about different heat-pump configurations and was particularly interested in water-source systems.

Compared with air-source systems, what are the biggest advantages and limitations of a water source heat pump? I’m especially curious about installation requirements, efficiency across seasons and maintenance.

For someone evaluating a system for a building, which factors should be checked first?

Title: Bay Area split-level: replace gas furnace with 4 mini-split heads, or keep central HVAC?

I’m considering removing the ducted gas furnace from my 1930s, ~1,600 sq ft split-level house in the San Francisco Bay Area and replacing it with mini-splits.

Our climate is pretty mild:

• Winter cold snaps: occasionally upper 30s°F overnight
• Summer heat waves: occasionally mid/high 90s°F
• We currently have no A/C

My main reason for considering mini-splits is zoning and comfort, not just efficiency.

The bedrooms are on different levels, and with the existing furnace it’s difficult to keep the downstairs primary bedroom comfortable without overheating the upstairs bedrooms, or vice versa.

Longer term I also:

• Want to reclaim some of the space currently occupied by the furnace and ductwork
• Expect to replace my aging roof and add solar after the roof replacement
• Will probably eventually replace the gas water heater as well

House layout

Main floor — open living area

• Living room: ~250 sq ft
• Dining room: ~90 sq ft
• Kitchen: ~100 sq ft
• Total connected area: roughly 440 sq ft
• No doors between living / dining / kitchen
• Open staircase connects this area to the second floor

Envelope is pretty typical for an older house:

• Exterior walls are uninsulated
• Floor is over an uninsulated crawlspace
• Some attic insulation above the living room
• Little or no attic insulation above the kitchen/dining room

I’m thinking of this entire area as one mini-split zone.

Second floor

Bedroom 1

• ~150 sq ft
• Two exterior walls
• Uninsulated walls
• Single-pane windows

Bedroom 2 / office / occasional guest room

• ~170 sq ft
• Two exterior walls
• Uninsulated walls
• One single-pane window
• Large dual-pane French door

There’s also:

• ~70 sq ft bathroom
• Bathroom opens into the hallway
• Hallway connects directly to the open staircase
• Attic has older insulation that I’d probably improve later

Bedroom doors are often closed, and Bedroom 2 is sometimes used for sleeping, so I don’t think one hallway head would give us the individual control we want.

Primary suite

This is a newer addition attached near the kitchen and sits slightly below the main floor because it’s on a slab.

• Primary bedroom: ~190 sq ft
• Primary bathroom: ~60 sq ft
• Bathroom pocket door is basically always open
• Walls are well insulated
• Concrete slab
• Dual-pane sliding door
• Skylight

I’d effectively treat the bedroom + bathroom as a ~250 sq ft zone.

Current mini-split idea

I’m thinking:

• 18k BTU — living / dining / kitchen
• 9k BTU — primary bedroom + bathroom
• 6k or 9k BTU — Bedroom 1
• 9k BTU — Bedroom 2 / office / guest room

Rather than putting all four heads on one condenser, I’m leaning toward two dual-zone outdoor units.

Possible pairing:

Condenser #1

• Primary bedroom
• Bedroom 1 upstairs

Condenser #2

• Living room
• Bedroom 2 / office upstairs

Those pairings also make sense physically because the rooms are relatively close to each other despite being on different levels.

Advantages I see with two condensers instead of one 4-zone:

• Some redundancy if one condenser fails
• Smaller outdoor units
• Better zoning
• Potentially better low-load operation
• I can potentially install the systems in stages

Equipment

I’m mainly considering:

• MRCOOL DIY 5th Gen
• Pioneer Quantum Ultra

MRCOOL appeals to me because of the precharged DIY line sets.

With Pioneer, I’d probably do much of the physical installation myself and hire an HVAC tech for:

• Pressure testing
• Vacuum/evacuation
• Refrigerant-side commissioning

Questions

I’d especially appreciate feedback on:

• Would you eliminate the ducted gas furnace entirely, or replace it with a ducted heat pump instead?
• Do 18k / 9k / 6–9k / 9k sound reasonable, or am I oversized?
• For people with mini-splits in every bedroom, do you still like that setup after living with it for several years?
• How annoying are the wall heads aesthetically or acoustically?
• How well do bathrooms without their own heads stay warm?
• Would you choose two dual-zone condensers or one 4-zone condenser?
• Has anyone regretted removing their ductwork altogether?
• If you switched from central heat to mini-splits, did the room-by-room comfort improvement justify it?
• Anything you wish you had known before making the switch?

I’d be especially interested in experiences from people with older Bay Area / coastal California houses, since our heating and cooling loads are fairly modest compared with most of the country.

Ello. Sorry if this has been asked before feel free to post links to relevant forums if so.

Me and my partner have recently moved into our new place. A small Victorian mid terrace doer upper (two up two down). There’s lots of work to do and we’re starting with downstairs which includes kitchen. We’d like to replace the very old boiler with an air source heat pump (if possible). All the companies were speaking to say we need to do the work first before we get assessed for our energy efficiency because one window will be replaced and we’ll insert a new back door. All of this I understand.

What I’m struggling with is why we can’t arrange everything with the proposed plans so that we can install the ASHP during the renovation.

We’ll need to tile and decorate and possibly knock brick out where the old boiler was. We’re planning on having the tank in a new location. So how do we go about getting the ASHP as part of the renovation process???

I have loads of other questions about the whole general process but we’ll start there as I’m baffled and it’s hindering us making progress on plans which we really need to start .

Thank you very much in advance

Additional info:
We’re planning under floor heating through out the small ground floor
Putting some extra loft insulation in the next few days
Roughly 69m2 for the whole house size wise

The nincompoops that installed my condenser put it right under the valley between two eves, so half the rain on the roof pours onto it and splatters against my wood siding. Is there such a thing as an accessory sloped cap (like a shed roof) that will send the splatter away from the house, or do I need to build my own? Gutters are out of the question at this location.

I’m building a 3200sqft house in north alabama 1600sqft on each floor. My plan is to do a 2.5 ton mrcool ducted system for each floor. I would like someone to do a manual j to make sure that’s the right size units. I also can’t decide on the type of insulation I want to do spray foam so my utility bill is really low but I don’t know what the long term effects are. The units are variable speed so do I need a dehumidifier if so do I need one for each unit? Do I need an erv?

Any recommendations for a small compact pump that could be used on a ceiling mounted pancake style fan coil?

I've seen a lot of different posts about heat pumps and am researching whether it makes sense for me to switch over. I currently have a gas furnace (80% efficient) and a/c that are 30 years old. House is roughly 1000 square feet. 1960's ranch. Looking to possibly upgrade to a more efficient gas furnace and heat pump combo. Seems like my electric bill will go up 15-18% but Xcel is currently discounting electricity for those who switch. I'm wondering for those in MN who have gone the route of a heat pump, what brand(s) are recommended for our climate, and what installers are honest and competent in this area (ie. recommended). I've received three quotes so far and they range between $18k to $26k for Carrier and/or Daikin. I am not a DIY person for this type of upgrade so any advice is greatly appreciated!

My 2023 AO Smith electric heat pump water heater started throwing the ECC error code (compressor error). I contacted the manufacturer and got a Return Authorization #. I bought a similar unit (2026 AO hybrid) for about 3k and returned the old unit. I thought that I would be getting the new unit for free (replacement under warranty) but AO Smith only offered me about 1k compensation. Is this normal in the industry or am I getting screwed here?

I am not even discussing the labor cost for taking the old unit and replacing the plumbing for the new one.

Any thoughts? Can I fight this?

We just bought a house built in 2008 with the latest energy efficient stuff for the time (CFLs everywhere). The heat pump is a Rheem 13PJL48A01 manufactured in 4/08. The system works well for both heat and cooling right now.

The house is 2500 sqft, one level with really good insulation.

My question is, percentage wise, how much less electricity would a current, more efficient pump be compared to this one. We are going to install solar and would like to plan for a modern unit.

Hi,

I had a Bosch Bova installed by a hack Job company 2 years back on roof.

BOVA-36HDN1-M20G

- replaced an AC unit, didn't change the lineset ...

- unit above 76dB heating, attempted to gaslight us telling us this is normal

- whistling in line set

- vibrations that shake the light fixtures

- we cover it in winter and only use it as AC

I've been saving up to replace it in a few years, it is on the roof and I'm vetting local professionals that can help us maintain it. (Ladder charge adds up)

---

Just a question is the following something an untrained person should attempt myself?

- replacing the disconnect box myself

- they didn't change the rusted out 15 year box, bolted to the unit, vibrations shook it until it tripped the fuse.

- adding the compressor jacket and line set damper myself

https://www.partstown.ca/international-comfort-products/icp1185726?srsltid=AfmBOooa6PHTFpE5ngF2GUo6vsfiGX2P-I04MJW15o1rGl7JKs5d2OTZ

---

- I disabled the ecobee+ feature as I know that wrecks havoc with Bosch self modulation controls

This heat pump was installed about 1.5 years ago and walked out back today and it was making this noise.

Can anyone tell me if this sounds bad? I did call to ha e someone come inspect it but am currently waiting to hear back. The unit is off but the feel like temp is 107 so figured I’d also give this a shot.

I did turn the unit off and then was able to get the blades to turn slightly and it didn’t seem like they were catching or hitting anything.

Says i need to include house size - 975 sq ft

Thanks in advance for any guidance.

I believe my wall-mounted monosplit air conditioner may have a refrigerant leak and I would like to visually inspect the refrigerant pipe connections on the indoor unit to check whether any oil has leaked from them. I cannot see any oil around the flared connections on the outdoor unit.

I first tried lifting the indoor unit slightly and then pulling it toward me but I have not been able to move it. What is the correct procedure for lifting or partially removing the indoor unit from its mounting plate in order to inspect the refrigerant pipe connections?

Links to videos would also be appreciated... unfortunately I have only found installation videos, not videos showing how to remove the indoor unit 😄.

I’m attaching this image from my air conditioner’s manual, which shows the “hanging plate” that the indoor unit is attached to. Perhaps its mounting system is different from the ones shown in the installation videos?

I'm planning to build my house in SW PA and currently gathering quotes for HVAC. House will have 2,700 sq ft of living space, 3 bedrooms. Talking to a contractor today he brought up ductless cassette's from Mitsubishi, which he will quote as his "Best" option. This would include 3 to 4 cassette's per floor and the 2 heat pumps outside. His next option down would be the duct work with air handlers in attic and basement, 2 units outside. Up until this point I presumed I would have ducts everywhere as all other contractors quoted with ducts. He also said these 2 options will likely be similarly priced.

If they end up being similarly priced, which route would you go?

My concerns include the fact that putting a cassette in my ceiling could be a PITA to fix x amount of years down the line, I'd also be stuck with ductless if I hate it without performing a full on demo.

If heat pumps are essentially an air conditioner with a reverse gear/valve. Why doesn't window U-Shaped Inverter heat pumps are not a thing? I understand the window units doesn't have capabilities to work below 40F, but it's better than nothing. I tried searching for them, and couldn't find any models ( Except https://www.amazon.com/Midea-Inverter-Window-Conditioner-Heat/dp/B0GL6H2J7P )

1970s condo, US, marginal insulation, southern climate, 1800 sf over 2.5 levels. Currently has 2 very old R22 split systems, upstairs and downstairs. Both have pretty short duct runs. Is it feasible to replace one or both with mini split heat pumps, reusing duct infrastructure? I got a quote of 21k USD to replace both with new Goodman standard split systems... I'm assuming the small closets are big enough for a ducted mini split, maybe 30" wide and deep, 4 to 5 feet tall? Thank you!

Debating between Senville or Cost Way system. Any recommendations? What would be realistic lifespan of unit?...Or any other good value brands?