Half the houses here have the whole system on the roof
FreshLine HVAC works on both kinds: rooftop package units and conventional split systems, in houses and in commercial premises across Simi Valley, Moorpark and the Conejo and west San Fernando valleys. Which one you have changes almost everything about what a repair or a replacement involves, and most people have never been told which they own.
A package unit is the whole system in one box, and it lives in the worst place on the property
In most of the country a house has a condenser outside on a pad and a furnace or air handler inside. Across a great deal of Southern California tract housing, including a large share of Simi Valley, it is built the other way: one sealed box on the roof containing the compressor, the condenser coil, the evaporator, the blower and the heater, with supply and return ducts dropping through the roof deck into the ceiling.
It was done that way because it is cheap to build, it needs no indoor closet and no attic clearance, and on a slab house with a low-pitched roof there is nowhere else to put it. Those are real advantages, and they are why so many of these houses have one.
What follows from it is less often explained. That box sits in full sun on a dark roof every afternoon of a Simi Valley summer, which is a harder life than the same equipment would have at ground level in shade. The ducts run through an unconditioned roof space or in the ceiling plane. Every repair involves getting onto the roof. And a replacement is not a straight swap — there is a curb to match, roofing to make good, and sometimes a crane.
None of that is a reason to be unhappy with a package unit. It is a reason to understand what you own before somebody quotes on it.
What we look at before quoting a roof job
- The curb: its size, its condition, and whether a current unit will sit on it without an adapter
- The roof itself — tile, shake or composition — and what has to be made good afterwards
- Access: whether the unit can be walked up, or whether it needs a crane and a street closure
- The duct drops, which are usually older than the unit and frequently the actual problem
- Electrical at the unit, and the condensate route, both of which age badly in full sun
Houses and premises are different jobs
We do both, and we do not pretend they are the same work. A house is judged on how it feels at four in the afternoon. A business is judged on whether it can keep trading.
Houses
Repairs, replacements, ductwork and maintenance for houses across Simi Valley and the surrounding towns. Most of the stock is single-storey slab-on-grade from the sixties and seventies, which means a package unit on the roof, a single large return grille, and duct runs that have been up there as long as the house has.
- Heat load calculated from the house as it stands, not copied off the old nameplate
- The one big return checked for size — undersized return air is the commonest cause of a noisy, struggling, short-lived system here
- Duct leakage and static pressure measured before the equipment is blamed
- Honest advice on repair versus replace on a unit that is already fifteen years old
Businesses
Offices, clinics, restaurants, salons, retail units, warehousing and light industrial space along the 118 and through the Simi and Moorpark business parks. Commercial premises usually have several rooftop units of different ages, and the useful thing is to know which one is going to fail next rather than to treat them as one system.
- Each unit assessed and reported separately, with its own remaining life
- Make-up air and exhaust balance for kitchens and treatment rooms
- Planned maintenance with readings recorded and compared year on year
- Staged replacement where a whole-roof swap cannot be afforded in one budget year
The package-unit page is there for people who will never call us
It answers the questions that are hard to ask a contractor who is quoting: what is actually up there, what a replacement really involves on the day, how long one of these should last and what shortens it, and whether converting to a split system is worth the money.
That last one matters most, because the conversion is the larger sale and it is very often the wrong answer. The page says so plainly.
Questions we get asked most
How do I tell whether I have a package unit or a split system?
Look at the roof from the street. One large metal box up there, roughly the size of a chest freezer, and nothing standing beside the house, means a package unit — the compressor, both coils, the blower and the heater are all inside that one box and the ducts drop straight through the roof into your ceiling. A square unit with a fan on top sitting on a pad at the side of the house means a split system, with a furnace or air handler indoors joined to it by two insulated copper lines. It takes thirty seconds and it matters, because almost every piece of advice you will read online assumes one or the other, and advice written for a split system is actively misleading if you own a package unit.
Should I convert my rooftop package unit to a split system?
Usually not, and it is the larger job so it is the one you will most often be steered towards. The part people underestimate is that the indoor half has to go somewhere: a single-storey slab house with a low-pitched roof often has no closet deep enough and no attic with the clearance or the structural support for an air handler and its drain pan. On top of that you are paying for a condenser pad, a refrigerant line set run through the structure, a condensate route that has never existed, electrical to two locations instead of one, a plenum transition onto ducts built to come down from above, and a roofer to close the opening. It is genuinely worth it on a two-storey house, where the roof is being replaced anyway, or where a usable closet already exists. It is not an energy-saving measure that pays for itself, and we will tell you in writing which case yours is before quoting it.
How long should a rooftop package unit last here?
Twelve to eighteen years is the usual range in this valley and plenty go longer. What pushes one to the short end is almost entirely controllable: a starved return, which is the biggest killer here and usually caused by an undersized grille or a filter denser than the system was built to pull through; a condenser coil packed with dust and brush debris so the unit cannot reject heat on a hot afternoon; blocked condensate, which on a roof unit announces itself as a ceiling stain long after the damage started; and nobody ever going up there to look. Annual service is not an upsell on this kind of equipment — it is the difference between twelve years and eighteen.
Why does my house cool fine in the morning and give up after three?
That is a load and distribution problem, not a capacity problem, and fitting a bigger unit usually makes it worse rather than better. By mid-afternoon the roof and the roof space are at their hottest, the west-facing rooms are taking direct sun, and any duct leakage is losing conditioned air at the worst possible moment. The honest sequence is to measure static pressure and duct leakage first, check the return is not starving the system, and look at attic insulation and shading. Those usually cost less than new equipment and they fix the actual complaint. We measure before we quote for exactly this reason.
Do you re-roof, or arrange the crane?
We do not re-roof and we do not repair roofs — that is a roofer, and we name one rather than absorb it into a price. Where a changeout needs a crane we arrange it and bill it as what it is, as a separate priced item, because it is a real constraint with its own scheduling and sometimes a street permit. We also will not quote a roof changeout without going on the roof: the curb and the roof covering decide most of the cost, and a price given from the driveway is a guess that gets revised upwards on the day.
Which areas do you cover?
Simi Valley, Moorpark, Santa Susana, Oak Park, Thousand Oaks, Newbury Park, Chatsworth and Porter Ranch.
Tell us what it is doing
Call and describe it. If it is something you can check yourself in two minutes we will say so on the phone rather than book a visit, and if it belongs to a different trade we will tell you which one.
1263 E Jefferson Way
Simi Valley, CA 93065