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After the storm, and before the next one
What surge protection does for air conditioning equipment, what it does not, and what to check when something has already gone wrong.
The check
This is about equipment, not about electrical safety inspection — where the two meet, an electrician or the utility decides first. It runs in your browser and nothing is sent anywhere.
What to do
Protection is layered, and the layers are not interchangeable. In order of what they do:
- A device at the panel, sized and installed by an electrician, deals with what arrives on the supply.
- A device at the equipment disconnect deals with what gets past it and with surges made inside the house.
- Sound bonding and grounding, because every device above depends on it and older houses often fall short.
- Switching the system off at the breaker when a severe storm is overhead, which costs nothing and works.
A breaker that trips during a storm and resets cleanly may have done exactly its job. A breaker that trips again is telling you something.
- Reset it once. If it holds and the system runs normally, watch it for a few days.
- If it trips again, leave it off. Repeated resetting into a fault damages more than it fixes.
- Listen at the first start: a hum with no fan, or a start that lasts seconds, both mean switch it off and call.
- Tell us it tripped after a storm when you book — it changes what we bring.
Surge damage is often partial: a control board that works intermittently, a contactor that chatters, a thermostat that has lost half its functions, a motor that runs hot.
- Note exactly what is different — the symptom is the diagnosis here more than usual.
- If anything smells hot or electrical, switch it off at the breaker and leave it off.
- Have it looked at before the next hot week rather than after. Partial damage rarely gets better.
- If you intend to claim, photograph everything before anyone works on it.
A system that is completely dead after a storm has usually lost a fuse, a contactor, a board or a transformer — but it can also mean damage further back, which is not ours to touch.
- Check that the breaker is on and the service switch by the outdoor unit has not been knocked off.
- Do not open the disconnect or the panel yourself, and do not stand in water to reach either.
- If there is any sign of burning at the meter, the panel or the service entry, that is the utility and an electrician before it is us.
- Otherwise book the visit and say it died in a storm — that tells us to bring boards, contactors and fuses.
No protection fitted. That is common and it is fixable. The panel device is the first step and it is an electrician's job; the device at the equipment we can fit when we are there. Neither is a guarantee — protection reduces damage, it does not promise none.
A panel device is a good start. Surge devices wear out, often silently, and many have an indicator that nobody checks. Ask for it to be checked after any significant storm, and consider a second device at the equipment.
Both layers fitted. That is the sensible arrangement. Have the indicators checked after big storms — a device that has taken a hit may have protected the equipment and finished itself doing it.
Worth finding out. A surge device at the panel is usually a small module beside the breakers; at the equipment it is a box at the disconnect. We can tell you what you have on the next visit, and whether it is still alive.
Four honest limits
- Protection is not insuranceA device reduces the energy that reaches the equipment. A direct strike can exceed anything fitted, and we will not pretend otherwise.
- Devices have a lifeThey absorb damage until they cannot. Many fail quietly, which is why the indicator matters and why checking it belongs on a maintenance visit.
- Grounding does the heavy liftingProtection that cannot get energy to earth does very little. In older houses this is the part that needs attention first.
- We do not do the panel workFitting at the panel is an electrician's job and we will say so. We fit at the equipment, test what is there, and coordinate with your electrician.
