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Aquastat - Oil -Gas Boiler Interchangable?

wgardner26 Member Posts: 9
Hello - I have a Crown CXE-5 (1997 vintage) gas boiler (150k BTU/HR, not high effiecency). I recently noticed the Honeywell L7224U1002 Aquastat a tech installed over a year ago is specified for use it oil boilers. Should I be concerned? My mechanical aquastat had failed.

Also, when scrolling through the digital settings on the Aquastat I noted the low temp cutoff is turned off. Is this correct? The high point is 199 and the differential is 10. I have 4 zones serving 3 baseboard loops and an indirect DHW tank. One circulator. I live in the northeast. I had the unit cleaned/inspected last fall with no issues. I have read some threads,with no firm conclusions, regarding cold start vs maintaining the boiler warm. I should note that the boiler temp never seems to exceed 140 and can linger in the 110 -120 range for very long periods in the winter (likely related to my system's inability to maintain the house temp during the winter).

Thank you.


  • Paul48
    Paul48 Member Posts: 4,469
    edited October 2016
    I'd suggest you get a qualified pro in to check the system out. You most likely have a problem. The fact that a cast iron boiler never seems to exceed 140, and lingers in the 110-120 range, is cause for concern. If you take those facts and add them to the fact the boiler doesn't heat the house properly, there is definitely a problem.
  • wgardner26
    wgardner26 Member Posts: 9
    Paul - Thank you for your response. The service tech verified with Honeywell that this Aquastat can be used on my gas boiler. Apparently, this oil boiler aquastat has a 120v tap that is needed in my case to run the induction blower. He also reviewed the system and did not note any obvious problems. It was a warm day, so he did not witness the system being overwhelmed by cold weather. I will post a separate entry with details regarding my system.