Apartment building boiler replacement
Domestic hot water boiler options, staged cutover and temporary hot water.
Commercial Water Heater Replacement for California Apartment Buildings
Replacing a central or multi-unit water heater plant while residents still need hot water. For California apartment, condo, senior and affordable housing buildings.
Multifamily buildings only. Not for restaurants, offices or retail.
- California multifamily onlyApartment, condo and affordable housing buildings.
- Central plants and in-unit heatersWater heaters, DHW boilers and central heat pumps.
- Incentive check includedCurrent program status reviewed for your address.
- Free, no-obligation assessmentFor owners, managers and authorized representatives.
Commercial water heater replacement in an apartment building is a different job from a restaurant or office. Dozens of households depend on one plant, so the cutover is planned around them, not around the equipment delivery.
Who this is for
Owners and managers of California multifamily buildings: apartments, condos and HOAs, senior housing and affordable housing. If you run a restaurant, office, hotel or other commercial building, this site is not the right fit.
Commercial water heater replacement or repair?
Some problems point clearly to replacement. Others are worth a repair quote first.
| What you see | What it usually points to |
|---|---|
| Water leaking from the tank body | Replacement. A leaking storage tank shell generally cannot be repaired. |
| Leak at a valve, fitting or pipe | Often a repair. Have the leak located before deciding. |
| Residents run out of hot water at peaks | Could be failing equipment, a lost tank, a bad mixing valve or a recirculation fault. Investigate before upsizing. |
| Equipment near or past its expected service life | Plan the replacement now, while you can choose the timing. |
| Parts discontinued or hard to source | Replacement, before a failure leaves you waiting on parts. |
Emergency replacement: the first 24 hours
This site does not dispatch emergency crews. If a plant fails, these steps protect residents and make the permanent replacement faster.
- Shut off and isolate the failed equipment. Keep water away from electrical equipment.
- Call your existing plumbing or service contractor for the immediate repair or isolation.
- Tell residents what happened and when you expect an update.
- Ask about temporary hot water: a temporary water heater or boiler connected to the system, if the plant room allows it.
- Photograph nameplates, tanks, venting and piping. Those photos speed up the replacement scope.
- Request an assessment for the permanent replacement, so you are not locked into whatever is on the truck.
Equipment options
Like-for-like gas storage
Replace the existing heaters and tanks with current equivalents. Usually the smallest change, but the venting, gas supply and clearances still have to suit the new units.
Tankless array
Several tankless heaters on a common manifold, often with a buffer tank. Saves floor space, but needs enough gas supply and a vent for each unit.
Conversion to a central heat pump water heater
Electric heat pumps with larger storage. A bigger project that depends on outdoor or ventilated space and electrical capacity. See central heat pump water heaters.
Sizing basics
Don't size the new plant from the old nameplate. The old equipment may have been oversized, undersized, or sized for a building that has since changed.
A designer works from peak demand, storage and recovery, and recirculation losses. The commercial water heater sizing guide explains each input.
Cutover in an occupied building
- Resident notice: agree who sends it, how far ahead and in which languages.
- Phasing: replace one heater or tank at a time where the piping allows, so part of the plant stays live.
- Timing: schedule shutdowns outside morning and evening peaks. After-hours work changes the price.
- Temporary hot water: decide early, because connections and space have to be planned.
- Return to service: confirm who checks temperatures at distant apartments before the crew leaves.
Permits and code
Water heater replacement in California needs a permit from the local building department. The state energy code (Title 24) and local air-district rules can affect which equipment is allowed and how it is installed. The contractor confirms the requirements for your address.
What drives the cost
The price depends on what can be reused and how hard the site is to work in. The biggest drivers:
- Equipment type and number of heaters and tanks
- New venting, gas piping or condensate drainage
- Crane, rigging or a difficult access route
- After-hours work and temporary hot water
- Electrical work if converting to heat pumps
The assessment produces the actual number for your building. For more detail, read what drives replacement cost.
Service area
Requests are accepted from multifamily buildings anywhere in California. Contractor coverage is confirmed for each property when the request is reviewed.
Owner questions
Commercial water heater replacement questions
Do you handle water heater replacement for restaurants, offices or retail?
No. This site covers multifamily residential buildings only: apartments, condos, senior housing and affordable housing in California. Restaurants, offices and other commercial buildings should contact a commercial plumbing contractor directly.
Can we replace the water heaters with the same model?
Sometimes. A like-for-like swap still has to meet current code, and the old model may be discontinued or no longer allowed in your air district. Venting, gas supply and clearances are checked before a direct swap is confirmed.
How long does a commercial water heater replacement take?
It depends on the scope: equipment lead time, permits, crane or access needs and how the cutover is staged. The contractor gives a schedule after the site survey. A like-for-like swap is usually shorter than a conversion to heat pumps.
Is this an emergency replacement service?
No. If hot water has failed today, call your existing plumbing or service contractor first. Use the form when you are planning a replacement, including one that follows an emergency repair.
Related guides
Boiler replacement cost
What drives the price of a boiler or water heater replacement, and how to get a firm quote.
Central heat pump water heaters
Equipment types, storage, siting and electrical readiness for a central plant.
Commercial water heater sizing
The inputs a designer needs to size central water heating for apartments.
Multifamily water heater rebates
California programs to check, with dated status and an eligibility checklist.
Water heaters for apartment buildings
The three ways apartment buildings make hot water, and how to choose.
Planning a replacement at an occupied building?
Send the building details once. Qualified requests go to a California contractor partner for a free, no-obligation assessment and quote.
Two short steps
Request a free assessment
The assessment and quote are free, with no obligation. Tell us about the building and the hot water equipment that serves it. An uncertain equipment age is fine.
- Central plants, DHW boilers and in-unit heaters at California multifamily properties
- With your consent, details go to a qualified California contractor partner who follows up
- Helpful later: nameplate photos, recent service notes and access constraints
This form is not an emergency dispatch service. If hot water has stopped, use the building's existing maintenance contacts.