Heat pump for a manufactured home: the crossover is the job

A manufactured home is built to HUD’s construction standard, not the same residential code as a stick-built house. The ducts often live in the belly, the space under the floor. On a double-wide, a flex crossover joins the two halves. If that hose is on the dirt, crushed, or torn, a new outdoor unit just pushes air into the crawl.

This is a hire guide. You are not hanging a wall head as a Saturday project through the marriage line. Heat pump vs furnace is still the machine fork. Ducted vs ductless is how the heat gets into rooms. Stay here until someone has looked under the home.

DOE’s buildings office is blunt about factory HVAC: the systems that ship with manufactured housing are often cheap to buy and expensive to run because the ducts leak. Their Slipstream project is about new homes leaving the plant ready for a heat pump, not about promising your 1998 single-wide a 57 percent cut. That 57 percent figure is a fleet estimate for new production, not your bill.

DOE: reimagining HVAC for new manufactured housing

Look under the home first

HUD’s circulating-air rule for manufactured homes is 24 CFR 3280.715. The manufacturer has to give instructions for supporting, fastening, sealing, and insulating each crossover. No portion of that duct is supposed to touch the ground. Crossovers and other ducts exposed to outside air under the chassis need R-8 insulation and a vapor retarder, and they have to be listed for exterior use.

Joints have to be mechanically secured and substantially airtight. Tape alone on a crushed flex run is not that.

eCFR: 24 CFR 3280.715

ENERGY STAR’s manufactured-home program says the same thing in plainer language: for multi-section homes, the crossover must be tightly sealed and must not rest on the ground. Ducts in unconditioned space get R-8.

ENERGY STAR: manufactured new homes program requirements (PDF)

Weatherize before the heat pump is still the order of work. On this house that means the belly board, the skirting, and the crossover, not only the attic. A patched belly and a hanging, insulated crossover can be the difference between a ducted swap and a whole-home mini-split.

If the installer will not go under the home, find one who will. A driveway quote that never names the crossover is a quote for a different building.

Ducted, ductless, or a packaged box

EnergySage’s 2026 marketplace average for an air-source heat pump is $15,393 before incentives. Ducted averages $14,529. Hybrid (heat pump plus furnace) is $14,353. Whole-home ductless is $25,957. Per ton, ducted is about $3,790 and ductless about $9,163. Those are mostly site-built quotes. A single-wide is fewer tons. It is not automatically cheaper if the belly work or a panel upgrade is in the same envelope.

EnergySage: air-source heat pump costs (2026)

Ducted, if the ducts are off the ground, sealed, and actually reach the rooms. You reuse the floor registers. You still need a load calculation for this envelope, not a rule of thumb from a two-story colonial. Manual J in plain English is that paperwork.

Ductless mini-splits, if the belly is junk, there is no crossover, or the park will not let you set a packaged unit on a pad. One outdoor box, line sets through the wall, heads in the rooms you live in. EnergySage’s whole-home ductless number is the expensive version because each head is another evaporator and another hole. A one- or two-head job for a single-wide is a different bid than five heads on a ranch.

A packaged unit on a pad beside the home, tied in through a listed exterior duct, is how a lot of older parks already cool. HUD 3280 treats those connecting ducts as part of the supply system, or as part of the listed appliance. The crossover still cannot sit on the dirt. A new package heat pump on a torn hose is the same failure with a new compressor.

Ask whether the equipment is listed for manufactured-home use, and whether the park or the community has a rule about outdoor units, pads, and line-set routing. HUD built the house. The park can still say no to the pad.

The panel, the belly, the federal line

EnergySage flags 100-amp panels as a common extra when you electrify. Manufactured homes often ship with that smaller service. 200-amp panel upgrade cost is the fork: a box swap versus a real service change. HomeGuide on that page puts a 100-to-200 jump around $1,300 to $1,600, or $1,800 to $2,500 if a new service panel is required. Get that in writing before the heat-pump bid pretends the outdoor unit is the whole job.

Federal 25C does not apply to property placed in service after December 31, 2025. A 2026 install does not get that IRS line. Ask the contractor to take last year’s credit off the quote. Utility and state money can still exist. How to check your rebates is that homework. Federal 25C expired is the date table.

IRS: Energy Efficient Home Improvement Credit

Do not let anyone guarantee a bill cut. DOE’s 57 percent is a research case for new homes with tighter envelopes and heat pumps, stacked across hundreds of thousands of future units. Your crossover and your panel decide what you actually bought.

What usually blows the manufactured-home number

A ducted bid on a crossover lying in the mud. HUD says it cannot touch the ground. Fix the hose or switch to ductless. Do not put a $14,529 average machine on a $40 flex that is already failed.

Sizing from square footage like a stick-built ranch. The belly, the metal roof, and the single-pane windows change the load. Demand a written calculation for this home.

A 100-amp panel left off the envelope. The outdoor unit is one invoice. The service is another.

A park rule that shows up after the pad is poured. Ask the office, in writing, about outdoor equipment, noise, and who owns the dirt the pad sits on.

Federal 25C still subtracted on a 2026 finish date. That line is $0.

Skipping the belly because “the registers blow.” Registers can blow while half the air never leaves the crawl. Have them show you the crossover, supported and off the ground, before you sign.

Two envelopes, same single-wide

Bid A, ducted swap. EnergySage’s ducted average is $14,529. On a small manufactured home the tonnage is lower, so the machine can come in under that, if the crossover is already legal. Add belly patch, R-8 flex, and supports. Add a 100-to-200 panel at $1,300 to $2,500 if the door says 100. A $9,000 outdoor-unit-only number that skips the crawl is not the cheap job.

Bid B, two-head ductless. Whole-home ductless at $25,957 is four or five heads on a site-built house. Two heads on a single-wide is a different envelope. You still need a load calc, a panel check, and park permission for the outdoor box. You skip the belly ducts.

If Bid A is $8,400 and Bid B is $11,200, ask which one includes the crossover repair or admits the ducts are abandoned. The gap is often the crawl, not the brand.

What the driveway questions sound like

Did you go under the home, and is the crossover off the ground, sealed, and insulated to R-8 the way HUD 3280.715 describes?

Is this equipment listed for a manufactured home, and does the park allow the pad and the line sets?

Ducted, ductless, or packaged, and why that fork for this belly?

Where is the written load calculation, not a rule of thumb?

What does the panel door say, and is a 100-to-200 jump in this number?

Is any federal credit in this quote for a 2026 placed-in-service date? If yes, take it out.

Who patches the belly board and the skirting after the duct work?

How do I decide this week?

Go under the home, or hire someone who will, before you pick a brand. HUD wants the crossover off the dirt.

Match the machine to the ducts you actually have. EnergySage ducted $14,529 if the belly works. Whole-home ductless is $25,957, which is not a one-head job. Packaged is the pad-and-listed-duct version.

Price the panel as its own line when the door says 100 amps. HomeGuide’s 100-to-200 band is $1,300 to $2,500.

Take 25C off a 2026 quote. Check the utility instead.

If the same crew wants to talk geothermal or a site-built furnace swap, send them back to this envelope. Geothermal vs air-source is a loop in the yard. You have a belly and a HUD label. Start there.