Weil-McLain 550-141-830/1202 manual Rapid cycling - burner turns

COMMON PROBLEMS	COMMON CAUSES	POSSIBLE CORRECTIONS
Rapid cycling - burner turns	Thermostat installed where drafts or	Locate thermostat on inner wall away from
on and off frequently.	heat affect reading.	heat sources or cool drafts.
	Heat anticipator in thermostat	Adjust heat anticipator to match current
	adjusted incorrectly.	draw. Refer to boiler wiring diagram.
	Incorrect limit setting.	Have qualified service technician increase
		limit setting to decrease cycling. Normal
		operation is usually less than 5 psig.
Need to frequently add	Leaks in boiler or piping.	Have qualified service technician repair leaks
makeup water.		at once to avoid constant use of makeup
		water.
Popping or percolating noise	Mineral deposits in sections due to	Have qualified service technician de-lime
heard in boiler.	constant use of makeup water. or	boiler and repair leaks at once to avoid
	incorrect pH.	constant use of makeup water and check
		pH (7.0-8.5).
Metal flakes found in flueway.	Contaminated combustion air supply.	Remove sources of hydrocarbons in or
		near boiler area. (Bleaches, cleaners,
		chemicals, sprays, fabric softeners, paint
		remover, etc.)
	Condensation of combustion gases.	Have qualified service technician check
		boiler operation.
Isolated radiation does not	Air vents or traps inoperative.	Have qualified service technician repair,
heat.		clean or replace air vents or traps.
Water disappearing from	Incorrect Hartford Loop piping.	Have qualified service technician pipe boiler
gauge glass and back into		exactly as shown in Boiler Manual.
system through return piping.
	Check-valve inoperative.	Have qualified service technician clean or
		replace check-valve.
	Vacuum-breaker inoperative.	Have qualified service technician clean or
		replace vacuum breaker.
Violent waterline fluctuations	Dirt, oil or other impurities in water.	Have qualified service technician skim
- surging.		boiler.
OR
	Waterline too high.	Have qualified service technician adjust
Water passing into steam
		waterline to normal height.
mains - priming.
	Incorrect piping.	Have qualified service technician pipe boiler
		exactly as shown in Boiler Manual.
	Sudden release of boiler steam	Have qualified service technician adjust
	pressure by action of zone valves.	valve operating time or install slow-opening
		valves.
Domestic water from tankless	Mineral deposits insulate internal	Have qualified service technician delime or
heater is hot then suddenly	waterways of heater.	replace coil.
turns cold.
	Boiler stop-leak compound has been	Have qualified service technician remove
OR
	added to boiler water and is insulating	and clean coil AND drain and flush boiler to
Domestic water from tankless
	outside of coil.	remove stop-leak.
heater is always lukewarm.
	Incorrect mixing valve setting for	Have qualified service technican adjust
	tankless heater.	mixing valve setting.
	Domestic flow rate too high.	Have qualified service technician install flow
		check valve set to rating of tankless heater.
	Incorrect setting on tankless heater	Have qualified service technician raise
	control.	tankless control setting. Adjust differential
		on tankless control to lower setting.

The problems and corrections above represent common situations that can occur. There may be others not listed above. It is important always to contact a qualified service techni- cian if you have any questions about the operation of your boiler or system.

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