gas-fired water boiler does not start;

sba

Hi, my gas-fired water boiler does not start; the pilot is fine, so gas is there, thermal fuse is fine. Pilot is automatic (i.e. not permanent & starts only when needed) so control is fine. It seems the gas does not flow thought the main pipe but I do not know why.

Pilot goes on for 15s then goes off.

i would need help to figure out what the issue is.

JUGHNE

Cleaning flame sensor often fixes this.....easy and free.

If a rod or part of the spark ignitor easy to clean with steel wool.

If a combined hot surface ignitor combined with sensor function, not real cleanable.....fragile.

It may glow but not sense flame as needed to keep gas on.

Ironman

More info is needed, like make and model of boiler, gas components, etc.

If you don’t have the tools and training to work on gas, you’ll be safer having someone who does look at it.

Try the contractor locator above.

sba

thanks for your help.

it is a weil mclain 1135-605. Natural gas i guess

Ironman

Can you post a couple of pictures of the boiler and controls?

sba

here is a video https://www.icloud.com/attachment/?u=https://cvws.icloud-content.com/B/AYppbys5MpwSaoR_fNlJ9moSXtmdAXFtZOCD0JKqlfkV8M_AgXGNuWKT/${f}?o=AuSRVGojkvpE2qBpQe9STEP41rnO9lglBv7yFxqhZ00b&v=1&x=3&a=CAog4OkUR-sUCiIjDUsKI3Iu10GzIMl5_88lVOBC9V_SDn8SdxCnpJKV0y4Yp7SN6dwuIgEAKggByAD_V-E3D1IEEl7ZnVoEjblik2omxpvAcNn74wTtMbqFnSm9lWe8YGgA6IN_DE48DrmxUUecVy3DMnJyJvoWi--d91ueB5yogUXCUMWBHS7SxMuvFhhu_MfdCvvOJFIDNYUQ&e=1605464447&fl=&r=73C26AF6-8822-42FF-A76A-CF3D9C1D75AA-1&k=${uk}&ckc=com.apple.largeattachment&ckz=CF0F8D9C-4B66-4E61-A046-919B4FDF025E&p=50&s=e_zCQQDCdSgOjgO2iVHIqtQI-3M&uk=ydO8Wt9XjS4xjyICbh4WSA&f=IMG_6856.MOV&sz=52648722

mikeapolis

It would appear to be the flame sensor. Can you show a video of the pilot flame making contact with the sensor?
Thanks

sba

I ll make a video when I ll be back home.
Actually there no flame beside the pilot.

sba

here is the video - https://photos.app.goo.gl/toZSEDAfrjQUP4bB9
not easy to see the sensor since it is behind the pilot.
I can remove the cover of the boiler to get a better video.


thanks again for your help

JUGHNE

The pilot flame looks probably good enough.
Does the spark igniter have both of its "legs" in the flame?

sba

yes; the "legs" are in the flame

HVACNUT

A volt meter and manometer would be awesome about now.

JUGHNE

If you remove the flame roll out shield with the hole in it for pilot viewing you may reach the spark ignitor and carefully clean with a SS wire brush or a strip of sandpaper....I use a soft minor abrasive flexible sanding pad cut into strips.
Still shot picture first that we could see.
You need to clean both legs of this. Especially where the flame lands on the legs.
Do not change the spark gap or bend either of the legs.
Replace the shield and try again.
Let us know.

sba

I have cleaned it up; here is the video after (without the shield) there is a picture as well

https://photos.app.goo.gl/Npm8aNYKyMJZ8XPd8

mikeapolis

Pilot flame looks great, new thermocouple . Hire a pro to install it, they can verify the rest of the system while they’re out.