Why these three are a different conversation
Federal Pacific and Zinsco have a body of published research and regulatory attention behind the concern about them, which is why our guides on those two brands cite specific figures and why the recommendation there is direct. Pushmatic, Challenger and Wadsworth do not have an equivalent evidence base. Anyone quoting failure rates for these three is either borrowing numbers from the other brands or repeating something from the trade internet that traces back to nobody.
We are not going to do that, and it costs the argument nothing — because the case for replacing an obsolete panel does not rest on how often it fails. It rests on the fact that you cannot buy a part for it, that many of them cannot be switched off in one movement, and that they have been in service for forty to sixty years in a coastal climate. Those are checkable facts about your specific panel rather than a claim about a brand.
The parts problem, which is the real one
All three lines are out of production and have been for a long time. What exists is salvaged stock and refurbished units through specialist suppliers, which creates two distinct problems.
The first is a blocking problem. Adding a circuit means adding a breaker, and if breakers are not available then the panel is the reason you cannot have a charger, a heat pump circuit, a new kitchen or a sub-panel for the garage. Plenty of people meet their panel for the first time this way — not because anything went wrong, but because they wanted to add something and the panel said no.
The second is a quality problem. A breaker is a safety device whose entire purpose is to work correctly the one time it matters. Replacing a failed one with a used unit of unknown age, unknown storage history and unknown number of operations is not a satisfying answer, and refurbished does not mean tested to the standard a new device is manufactured to. On a sub-panel feeding a shed this is an acceptable compromise. On a main panel it is not one we would propose as a plan.
Split-bus panels and the missing main switch
This one surprises people, and it is worth understanding because it changes what you can do in an emergency.
A modern panel has a main breaker: one switch, at the top, that disconnects everything below it. Many older panels — including a large share of Pushmatic and Wadsworth installations — are SPLIT-BUS instead. The top section holds several large breakers feeding the major loads directly, and one of them feeds the lower section where the lighting and general-purpose circuits live. There is no single disconnect.
- Nothing turns the whole house off in one movement, and working out which combination does is not something to be doing under pressure
- The panel cannot be cleanly de-energised for work on it, which affects how any repair has to be approached
- The design predates modern expectations about service disconnects, and it is one of the reasons these panels read as obsolete to an inspector at a glance
- It is also why our advice about switching off the main during an emergency needs a caveat in these houses — there may not be one to switch
What we actually assess
Brand is where the conversation starts, not where it ends. What decides the recommendation is the panel in front of us.
- BUS CONDITION — corrosion, pitting, and any evidence of heat at the stabs where breakers connect. Near the coast this is the finding that most often settles it
- TERMINATIONS — whether connections are tight, whether anything has been overheating, whether previous work was done properly
- SPLIT-BUS or a proper main disconnect
- BREAKER OPERATION — Pushmatic mechanisms in particular stiffen when they have not been operated for decades, and a breaker that is reluctant to move is a breaker whose behaviour under fault is unknown
- CAPACITY against what you are planning to add, which is a separate question from condition and often the one that actually decides the timing
- THE SERVICE around it — an obsolete panel on a service that is itself due work is a different proposition from one on a sound modern service
Sometimes the honest answer is that the panel is in reasonable condition and the pressure to replace it is coming from a plan to add load rather than from the panel itself. That is worth knowing, because it changes the timing and sometimes the sequence — and because a written assessment saying so is useful when a carrier or a buyer asks.
What replacement involves here
Every main panel job we do is a full electrical service rebuild, whether it is an upsize or a like-for-like replacement at the same amperage. The service entrance conductors, the combination meter main, and the grounding and bonding all come up to current code alongside the new panel, breakers and a whole-house surge protector. This is worth saying plainly, because quotes that describe swapping the box for a smaller number are describing a smaller job than the one that has to happen.
On an OVERHEAD service the chain is weatherhead, mast, service entrance conductors, combination meter main, grounding. On an UNDERGROUND service there is no mast or weatherhead — the utility conductors come to a service point and terminate inside the combination meter main — and a like-for-like still needs PG&E to disconnect and reconnect at the splice. On an underground upsize the largest cost variable is whether existing conduit is two inches or larger and reusable, or whether new conduit has to be trenched; we assess the visible conduit when quoting, PG&E verifies after contract, and we requote if they require new conduit rather than springing it on you mid-job.
Most of these are a single day. PG&E disconnects, we rebuild, the AHJ inspects, PG&E reconnects, and you are without power for the working portion of the day — worth planning around if somebody works from home or there is medical equipment in the house. The panel we fit is Siemens unless you ask for another brand, and breakers always match whichever panel goes in, because mixing makers voids the UL listing of the assembly regardless of physical fit.
If yours is showing symptoms, stop reading
Everything above is a planning conversation. A panel that smells of burning, feels warm through the cover, makes noise, or has visible scorching is not a planning conversation. Switch off what you can safely reach, do not open the cover, and call. Obsolete brand or not, heat at a panel is heat at the connections that feed the whole house.