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toonice_gw

Aquastat Settings, and Hot Water Question

15 years ago

I recently purchased a home with a new yorker oil boiler(95' I've been told) that has a coil for domestic hot water, or summer/winter hook up and old cast iron radiators for heat. When I moved in the aquastat settings were the typical 180 HI, 160 LO settings. When we purchased the home we had a mixing valve installed before closing to prevent scalding. When trying to take showers, typically the water starts out hot, then goes to lukewarm-cool for some time, then after 5-10 minutes of the cool-lukewarm water, returns to hot again. Could this be due to the mixing valve, or settings on the boiler itself?

We had an HVAC tech out to clean the boiler, and while here he adjusting the aquastat settings to what looks like just under 150 on the LO. He left the HI unchanged...and said adjusting the LO would cut down on oil usage. I should mention that we have used 3/4 of a 250 gallon tank of oil in 3 weeks, which seems like a lot...but it has also been a very cold 3 weeks in PA. After the HVAC tech adjusted the LO setting, the showers got even colder. Without really knowing what I was doing, I adjusted the mixing valve higher which helped somewhat, but not completely.

Is there anything I can try, or adjust to help with this hot water problem? Should I move the LO setting back to 160 degrees, and keep the mixing valve high? Also, does the use of 3/4 of a 250 gallon oil tank in 3 weeks seem typical? Or is that a large amount? We usually have the thermostat set at 66 during the day, and 63 at night. The area that the thermostat is located does seem slightly colder than other parts of the house due to old drafty windows, which we plan to replace shortly. Would that help?

I should also mention that it appears the DIFF setting on the aquastat is set somewhere between 10 and 15. Is this okay? I know there are a couple questions here, but any responses would be very appreciated. Thanks

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