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Can I stop my oversized boiler from short cycling?
I guess my question is 2 part:
1. Anything I can do to stop my combi boiler from short cycling when moving between DHW and space heat calls?
2. Why does this only seem to happen when outside temps hit -25F and colder?
Issue: my Lochinvar Noble combi is oversized for the house. Space heat set point is 135F, DWH is 120F. If we use any hot water while there is a call for heat, the boiler cannot transition back to the space heat call without going into a short cycle. A new ignition flame will ramp up the 120 water right up to 145 and the boiler can’t modulate down quickly enough, and takes a 1 minute nap before repeating the cycle. We’ve had to resort to planning out any warm water use by ramping down our thermostats to ensure a call for heat won’t come around the same time we are using DHW. This mainly seems to happen during very cold spells of about -25F and colder, which alaska is experiencing a pretty long stretch of right now. However, I’m wondering if this has always been a problem and am just really noticing it now since the boiler is running for most of the day. Any easy solution to this? Thank you!