Lochinvar Combi-Boiler Missing Outdoor Air Sensor
We had a Lochinvar – NKC199N (199,000 BTU) combi-boiler installed last fall. Our house is only 1,600 sq/ft and decently insulated so it seemed like overkill, but had to do with hot water demand?
At the time of install the tech said the outdoor air sensor causes them a lot of grief so they usually don’t install them. I can imagine these guys are often installing them in direct sunlight, etc.. any way…
I noticed this summer the boiler would short cycle maybe 1-2 times of hour. Go through a pre-purge cycle. Assuming it’s trying to keep itself as hot as possible since it has no idea it’s summer outside.
Would adding the outdoor air sensor help with this? The utility closet is on the north wall so it would be very easy to drill through the frieze board and put it in.
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Replies
I am not sure that particular issue is going to be fixed by that. The outdoor sensor should modulate the output water temp to the heating loop according to the outside temp. Depending on settings you could see water down to 100F to the radiators.
Since the heating should not be running I don't think that is it.
Beyond that I am not sure how combi boilers handle hot water. It would seem very old school and wasteful to keep the boiler up to temp at all times. My 1970 cast iron oil boiler did exactly what you describe before I replaced it
Pretty smart guys at heatinghelp.com will have the answer