Boiler problem
Boiler will not turn on?
No sound, no flame, nothing. Simple causes to rule out first, and what a technician will check next.
This is a referral line. When you call, you are connected with an independent local heating company.
Check these first
- Thermostat set to heat and above room temperature, with fresh batteries.
- The boiler service switch and the breaker.
- Fuel: gas to other appliances, or oil in the tank.
- Water level on steam, pressure on hot water.
- An oil burner reset button. Press it once only.
Angi notes a tripped breaker or bad fuse is the cheapest fix, around $75 if an electrician is needed, while thermostat, condensate, fuel line or pressure problems cost more, up to about $1,800.[source]
What a technician checks
Power to the controls, the thermostat circuit, the transformer, the ignition system, the low water cutoff on steam, safety switches, and the gas valve or oil burner.
Frozen condensate lines
High-efficiency boilers drain condensate, and the line can freeze in deep cold. Angi notes a frozen condensate pipe can sometimes be freed with warm water, but most other causes need a professional.[source]
Work through the chain
A boiler needs four things to run: a call for heat from the thermostat, power, fuel, and water (and on steam, the right water level). Most no start problems come from one of those four or from a safety control that has locked out. Work through them in order before you call.
- Thermostat: set to heat, set a few degrees above room temperature, display working. Replace batteries if the screen is blank.
- Power: check the breaker and the boiler service switch. Look for any lights on the boiler.
- Fuel: for gas, check that other gas appliances work. For oil, check the tank gauge.
- Water: check the pressure gauge on a hot water boiler, or the sight glass on a steam boiler.
Error codes and lockouts
Most boilers made in the last twenty years have a display or a light that flashes in a pattern when something fails. The meaning is in the manual or on a label inside the cover. Write it down exactly before you reset anything, because a reset can clear it.
If the boiler is in lockout, many models allow one manual reset. If it starts and runs, note the time and watch it. If it locks out again, call. Repeated resets do not fix the cause and on oil boilers can be unsafe.
Snow, ice and the venting
High efficiency boilers vent through plastic pipes out a side wall, often close to the ground. Drifting snow, ice buildup or a blocked intake screen can stop the boiler. After a storm, check that the vent pipes outside are clear by a good margin. The National Weather Service Binghamton office posts forecasts for the Utica area, and a heads up on a lake effect band is a good reminder to check.[source]
Condensate lines that run outside or through cold spaces can freeze and back up, which shuts many condensing boilers down. If the boiler shows a condensate or drain fault on a very cold day, that is a likely cause.
When the boiler hums but does nothing
If the boiler has power and you hear the fan run but there is no ignition, the pressure switch, igniter or control is the likely problem. If you hear clicking but no fan, the inducer motor may have failed. If the burner lights for a few seconds and goes out, the flame sensor is the usual suspect.
Describe exactly what you hear and see, in order. That helps the technician bring the right part on the first trip.
Old boilers and standing pilots
Older gas boilers in Utica area homes may have a standing pilot. If the pilot is out, the lighting instructions are on a label inside the boiler. Follow them only if you are comfortable and you do not smell gas. If the pilot lights but goes out when you release the knob, the thermocouple is likely bad.
If you smell gas at any point, stop, leave the house and call 911 or the gas utility from outside.
What to tell the company
Tell them what you checked and what you found: thermostat calling, power on, fuel available, pressure or water level, any error code, and what you hear when the thermostat calls. Mention any recent work, a recent power outage, or a storm. A power surge can damage control boards, and a storm can block vents.
Frequently asked
The boiler runs but there is no heat. See no heat; it is likely circulation, a zone valve, or for steam, vents or water level.It started after a power outage. Reset the breaker and service switch, and check the thermostat. A surge can damage control boards; mention the outage when you call.It works sometimes. Intermittent failures often come from flame sensors, loose wires or pressure switches. Note when it fails and any code.Gas, oil and electric boilers differ
Gas boilers depend on the ignition sequence, so most no start problems involve the igniter, flame sensor, pressure switch, inducer or control. Oil boilers depend on fuel delivery, so the tank, filter, nozzle and pump come first, followed by the electrodes and primary control. Electric boilers have no burner; a no start there usually means a breaker, a heating element, a relay or the control.
Telling the company which type you have, and what the boiler does when the thermostat calls, cuts diagnosis time. If you are not sure of the fuel, look for a gas pipe with a yellow handled valve, an oil line coming from a tank, or only electrical conduit entering the boiler.
If the boiler has not run since last spring, the first start of the season is a common time for failures. A dusty burner, a seized circulator after months of sitting, or a pilot that went out over the summer can all show up on the first cold night.
Before the technician arrives
Clear a path to the boiler, put pets away, and find the model plate. Write down any error codes and what the boiler did when you tried it.
Keep the manual
Keep the boiler manual in a bag near the boiler. It lists reset steps and codes.
What to have ready when you call
- Your address, so the company can tell you if you are in their area.
- Boiler type and fuel if you know it: steam or hot water, gas or oil. A sight glass with water in it usually means steam.
- What it is doing, plus any code on the display or the reading on the pressure or temperature gauge.
Not sure about any of it? Call anyway. The company will ask the right questions.
Common questions
Why does my boiler start and then stop?
See gas boiler repair for flame and venting causes.
Is it safe to keep resetting it?
No. Reset once. If it fails again, call.
Still not sure what is wrong?
Call and describe it. A local heating company will take it from there.
Call about your boiler(888) 835-0429