Dvele Garage Conversion ADU: The San Bernardino Owner’s Guide
We stock and install Dvele-compatible garage conversion ADU components in San Bernardino, with most replacement parts available same-day and installed within one visit. A typical Dvele garage conversion ADU part replacement in San Bernardino runs $1,200-$4,800 installed, depending on whether we’re replacing a single subsystem or coordinating multiple integrated components. Most owners discover a problem when the Dvele smart monitoring system flags a fault, or when a climate-control, electrical, or structural interface stops responding as designed.
Which Dvele Models This Applies To
Dvele produces factory-built garage conversion ADU modules in several series, and the parts landscape differs significantly between them. The Dvele Home series uses a proprietary HVAC interface board (Part No. DV-HVAC-INT-22 and later DV-HVAC-INT-24) that is not backward compatible with the earlier Dvele Pod garage conversion units. If your unit was delivered between 2019 and 2022, check the electrical panel for a white label with a “DV-GC” prefix - this indicates the garage conversion-specific wiring harness, which uses a different connector pitch than Dvele’s detached ADU line.
We carry both OEM Dvele parts and quality aftermarket equivalents from Rheem, Schneider Electric, and Uponor where the specification matches. For the DV-HVAC-INT series specifically, we stock the OEM board because the firmware handshake with Dvele’s cloud monitoring is proprietary - an aftermarket equivalent will run the hardware but will not clear the fault code in the app. For plumbing manifolds and standard electrical breakers, we typically use aftermarket equivalents that carry the same UL listing at roughly 60% of OEM cost. We will tell you which choice we’re making and why, before we order.
Signs Your Dvele Garage Conversion ADU Is Failing

- The Dvele app shows a persistent “Climate System Offline” fault. This usually traces to the HVAC interface board losing communication with the central controller. In San Bernardino’s inland heat, the garage roof cavity where this board mounts can exceed 140°F in July, and we’ve seen capacitor degradation on the DV-HVAC-INT-22 series accelerate from a 10-year design life to failure in 4-6 years.
- Hot water runs cold at the kitchen tap after 30 seconds. Dvele garage conversions use a compact tankless unit mounted in the former garage’s utility chase. The heat exchanger scales hard in San Bernardino’s 280-320 ppm water hardness range, and the flow sensor - a small Hall-effect device - gums up first. We stock the replacement sensor and the descaling kit together.
- The floor near the original garage door header is damp after rain. Dvele’s garage conversion kit includes a threshold pan and integrated flashing, but the sealant bead at the header interface can fatigue. This is not a part failure in the traditional sense, but it requires Dvele-compatible header flashing (DV-GC-HDR-20 series) and proper sequencing with the existing slab edge.
- LED fixtures flicker or the subpanel trips on moderate load. Early Dvele garage conversion units shipped with a 100-amp subpanel that is technically code-compliant but leaves no headroom for EV charging or 240V appliances. We upgrade to a 125-amp or 200-amp panel using Dvele-compatible bus bars and breakers, with permit amendment included.
- The smart lock or entry system loses power intermittently. The low-voltage transformer in Dvele’s entry module is mounted in the exterior wall cavity. San Bernardino’s summer wall cavity temperatures can push this transformer past its 105°C thermal rating, causing thermal shutdown. We relocate the replacement to a ventilated interior chase.
Replacement Cost & What’s Included
In San Bernardino, Dvele garage conversion ADU part replacement typically falls in these ranges:
- HVAC interface board (OEM, with firmware sync): $1,200-$1,800
- Tankless water heater flow sensor + descaling: $680-$1,100
- Header flashing replacement with sealant detail: $1,400-$2,600
- Electrical subpanel upgrade (100A to 125A/200A): $2,800-$4,800
- Entry system transformer relocation + replacement: $890-$1,400
These are installed prices, inclusive of parts, labor, and the permit amendment or inspection coordination required. Under Haven Standard Clause 1, the written price you receive before work starts is the price you pay - no line-item additions once the scope is locked. The range reflects site access conditions (a finished interior requires more protection than an open garage) and whether we’re matching a single failed part or addressing the underlying cause that led to the failure. Our workmanship on ADU component replacement carries a 365-Day Done Right Promise: if the installed part does not perform as specified, we replace it at no charge.
DIY or Call Us?

There is a clear boundary here. A homeowner can safely check the Dvele app fault codes, reset the controller per the manual, and verify that breakers are seated - these steps resolve roughly 15% of the calls we receive. What we do not recommend: opening the HVAC interface enclosure (240V present even with breakers off, due to Dvele’s capacitor retention design), working on the tankless water heater gas connection, or disturbing the header flashing without understanding the original garage door load path. The header in a garage conversion ADU is often a engineered beam that was sized for the specific opening; removing sealant or fasteners without knowing the sequence can compromise the structural warranty.
We are an independent service provider, not affiliated with Dvele. Our technicians are background-checked, uniformed, and carry the specific Dvele part numbers on their trucks because we’ve done enough of these in San Bernardino to know what fails. If you’re unsure whether your symptom is user-serviceable, call (909) 359-6463 - we’ll walk through what you’ve seen and tell you whether it needs a truck roll. Estimates are free.
FAQs
The HVAC interface board is rated for 10 years but typically lasts 5-7 in San Bernardino’s heat, while the tankless flow sensor needs attention every 4-6 years due to regional water hardness. Call (909) 359-6463 and we can check your unit’s install date against the failure curves we’ve tracked.
Sometimes. A scaled flow sensor can be descaled in place, and we will recommend that if the element itself tests good. The HVAC interface board is not field-repairable - the surface-mount components and proprietary firmware load make replacement the only reliable fix. We test first, then tell you which path applies.
Most single-part replacements are completed in 2-4 hours of on-site time. A subpanel upgrade requires a half-day for the work plus SDGE coordination for the service disconnect, which we schedule as part of the project. You’ll receive a documented photo record of each phase.
We stock the high-failure items - HVAC interface boards, flow sensors, transformers, and common breaker sizes - on our San Bernardino service trucks. Specialized Dvele components ship from their Sacramento distribution center in 2-3 business days, and we coordinate delivery so the part arrives before we schedule the installation.
Written by Nadia Ellery, Owner, Ellery ADU Studio San Bernardino at Ellery ADU Studio San Bernardino, serving San Bernardino and nearby areas.