Can't find model # on aquastat

Old 10-04-20, 04:58 PM
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Can't find model # on aquastat

I think I'll be needing a replacement aquastat since the one on my domestic HW boiler has starting making loud and erratic clicking sounds. It's a very old Honeywell that only has 5 wires going to it. The only number I see is R19A. Question is what replacement aquastat should I order? I'm looking for something simple, perhaps universal. See attached photos.

Old 10-04-20, 06:02 PM
Join Date: Jun 2012
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Doesn't appear to be an Aquastat but just a transformer/relay combo. Direct replacement is Honeywell RA89A.

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