“A professional range is a gas appliance first and a kitchen fitting second, and in Cambridge it usually went in before the kitchen was finished around it.

It is not dangerous, but it is telling you something. Continuous sparking after ignition means the module is not seeing a flame at the sense electrode — usually a wet or dirty electrode after a boil-over, a burner cap sitting a millimetre off its seat, or a cracked porcelain insulator. Dry it, seat the cap square, and if it still clicks with a good flame the electrode or the module needs attention.

The service call is a flat $95 and it covers coming out and finding the fault properly. It comes off the bill when you approve the repair, and the repair price is given before anything is taken apart.

Sometimes, and that is the first thing checked. Most of these ovens have an offset adjustment for exactly this, and if the cavity is a consistent twenty degrees out with a healthy element and a sound door seal, an offset is the correct fix. A cavity that swings — right at one temperature and wrong at another — is a sensor or an element, and no amount of offset will settle it.

Not for the visit. Almost everything is done in place: burners, igniters, valves, elements, sensors, hinges, pumps and boards all come out through the front of the appliance. Worth mentioning when you book, though, because access decides how long a job takes and what gets carried up.

Often it is not. Standing water at the end of a cycle is a drain problem before it is a pump problem: a blocked filter, a check valve holding open, a drain hose without a high loop, or a disposal air gap that was never cleared after the last install. Those get eliminated first because they are quick and they are free.

Yes. The older sealed-burner ranges are mechanically straightforward and parts for the common wear items are still available. What changes with age is the electronics: an obsolete board on a very old unit is where a repair sometimes stops making sense, and you will be told that rather than sold a part.