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How to cold start my furnace to avoid cracks? Oil, forced hot water.
To avoid boiler cracks Is there a special way I need to start my house oil furnace from cold start, about 60 deg F. It's operating fine now , but I'm thinking if loose power from ice storm and it cools to 60 deg.
I'm thinking thermal shock/stress to it's cast iron during heat up.
In past I just turned it on, but now I'm wondering.
Forced hot water
60 year old National Sunray IV , boiler # 5-19A/O/OP , rated 128k BTU/hr 1.6 gal/hr
Has original burner, National -US model NB2-K2, firing rate .85-2.0 gal/hr, 1.1 gal/hr nozzle
Chimney is most 4 stories from cellar floor to top of it
Tankless coil in water jacket
Cast iron baseboards, 1ft tall .