How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Phil Your Own Question
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7737
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
23932409
Type Your HVAC Question Here...
Phil is online now
A new question is answered every 9 seconds

Weil Mclain gas boiler pilot light on flame is fine but will

Resolved Question:

Weil Mclain gas boiler pilot light on flame is fine but will not fire up system. it has a white-rogers cyle pilot ignition
Submitted: 5 years ago.
Category: HVAC
Expert:  Phil replied 5 years ago.

Phil :

All work to be done by licensed professional. WE KEEP GOING UNTIL YOU HAVE THE INFORMATION YOU NEED, I come and go. This is step ONE.

Phil :

Hello, we can address that issue, but first a word of caution... replacing various parts at random can lead to progressively more and more problems as many times the replacement parts are not exactly the same internally as the old part..or errors can be made in the wiring.

Phil :

in the current situation is is about 80% likely that the flame sensor is not detecting flame because it is dirty. and about 20% likely that the boiler is off on one of its safely controls.

Phil :

Look the units wiring diagram over and locate its flame sensor and tell me as much as you can about what you find.

Phil :

look on the unit for the actual item....

Phil :

We can go from there until this resolves.

Phil :

Phil

Customer:

The dsensor is a Mercury flame Sensor Weil Mclain # XXXXX Manufacturer White =-Rogers part No. 3098-149

Customer:

If you can walk me through a repair/replace I'll be glad to pay the $50.

Phil :

Hello, that sensor has been made illegal, and is no longer available, except at best through a Weil McLain dealer who will only sell to licensed boiler contractors for liability reasons.

Customer:

ouch

Phil :

Adapting a different sort of ignition control to a boiler is possible but involved to say the least, and costs more than a new boiler in many cases.

Customer:

I guess I have to call the repairman

Phil :

However an old cast iron McLain, as you have, will generally go 50 years or longer...and from today outlast any of the new high efficiency boilers on the market (average life span seems to be 10 years, as a result of light weight heat exchangers and fragile electronic components.)

Phil :

There is a chance that over time one might show up on ebya.

Phil :

I will check

Phil :

You are in luck!! act *fast

Phil :

http://www.ebay.com/sch/i.html?_kw=flame&_kw=sensor&_kw=control

Phil :

We can go from there.

Phil :

Phil

Phil :

those are $250 from McLain if they will even sell you, most will not

Customer:

this boiler was bought by the previous owner in 1987. I know I had trouble with the ignition before but the boiler has never been a problem I will check the ebay listing

Phil :

For $49 you might want both of them... getting one a few years from now might be virtually impossible... the boiler itself might last another 50 years.

Phil :

Phil

Phil :

http://www.ebay.com/sch/i.html?_kw=flame&_kw=sensor&_kw=control

Phil :

just in case :)

Customer:

the sensor looks right but the part # XXXXX my parts list says 3098-149 and the ebay says 3098-156 does that seem like a problem and yes both seem smart

Customer:

I am accepting the charge for your help, thank you and hope you can help me with a walk through if I go ahead with the ebay listing I don't see any on line directions for replacing this part.

Phil and other HVAC Specialists are ready to help you

Related HVAC Questions