Lockinvar cadet combustion chamber whining (and advice request on a new unit)

dhw_probs

The whining seems to be the combustion chamber-- motor is silent. It's not a single constant whine, it's more like countless short whines about 1 second long all overlapping each other. This was during DHW. What might this be?

This unit is only few years old and I've had constant problems since the begining  It gets annual maintenance but still breaks down 2-3 times a year. In the last 6 months alone I've spent over $1500 on it. It seems high efficiency systems are finicky and have specialized parts. I'm ready to replace this one with a normal efficiency unit. My current one is 120000 BTU and when working properly fits our needs just fine, running at 30-40% when putting out heat on cold days.

Any recommendations on brand & model for a normal efficiency unit? My current unit is a combi for heat and hot water, do normal efficiency units do both or would I then need a separate hot water heater? Also, I'm in NY metropolitan suburban area. What should I be looking for on the price of the unit and price of the labor when getting quotes? Everything is plumbed for the current system, so I don't know if that needs significant changes, but I'm just looking for a ballpark range so I can properly evaluate quotes.

Thanks!

hot_rod

Are you sure it is installed properly? I've had a Cadet since they were offered, without a single problem.

Whining on DHW high fire might indicate an undersized pump, or mispiping. They need a medium head circ as per the manual.

Combustion adjustments, or lack of, can also cause a whine noise.

EBEBRATT-Ed

@dhw_probs

We can't discus pricing on this site.

What @hot_rod said. Sounds like you need a new service tech. Check 'find a contractor" on this site. Maybe @JohnNY

MOD Cons can be finicky and parts are $$$ but without the right technician your lost.

Maybe call lockinvar and express your frustration and ask them for a recommendation.

dhw_probs

@EBEBRATT-Ed I went through Lochinvar for my current techs, which are a large(ish) company that services homes & companies and has people who specifically know Lochinvar units. They consulted with Lochinvar on the last issue I had, and unfortunately Lochinvar got it wrong and cost me $500 for an unnecessary repair + $150 for what ultimately fixed the issue. So I feel pretty much done with Lochinvar. I know they're supposed to be solid units, but I'm spending a heck of a lot more on repairs than I save in natural gas for the extra 15% efficiency.