Burnham Boiler Issue

Old 04-06-21, 10:23 AM
Thread Starter
Join Date: Apr 2021
Posts: 1
Received 0 Votes on 0 Posts
Burnham Boiler Issue

Hi all
Having a problem with a Burnham oil fired baseboard hot water boiler. Found the boiler in in a safety lock out. Pushed reset button furnace fired for 40 second and then it shutdown. Plenty of fuel(1/2 tank plus) tried again, same result. Checked CAD cell, Ohm readings seem off so I replaced it this morning. Boiler fired and stayed lit. Problem is, the boiler temp started to climb, but circulator pumps did not start, just as I was about to shut boiler down pressure release valve opened. I replaced the aquastat along with the CAD cell primary relay last year so they should be good, however I have not checked with meter. Any suggestions before I start wasting money swaping out parts? Thanks.... Bill
Old 04-07-21, 05:51 AM
rbeck's Avatar
Join Date: Jul 2007
Location: United States
Posts: 2,625
Received 40 Votes on 34 Posts
If this is a warm start boiler which means the boiler maintains temperature usually to the boiler have a domestic hot water coil in the boiler the circulator will not start until the boiler temperature rises above the low boiler setpoint.
As far as the relief valve blowing water that is a result of water logged expansion tank or low air charge.
If the tank is a steel tank normally hanging between the floor joists it would require a tank isolation with a valve, complete drain of water and allow air to enter the tank to recharge. The tank refills when the isolation valve is opened.
The bladder type tank first check for a defective bladder by depressing the valve on the bottom of the tank to see if you get water. If so replace the tank. If not remove water pressure from the boiler and recharge the tank to equal you system fill pressure.
This would not be a bad water feeder or leaking domestic hot water coil because the relief valve would have been leaking even if the boiler was not running.
spott voted this post useful.
Old 04-07-21, 06:39 PM
Join Date: Apr 2014
Location: us
Posts: 1,451
Received 91 Votes on 85 Posts
Any suggestions before I start wasting money swaping out parts?
OldRattler has multiple problems. Suggestion is to start by by checking basics: reason for burner lockout, water temperature 140F to 180F, pressure 12 psi, and venting.

1.Install modern burner control that displays real time status and reason for shutdown.
See DH posts #14 #16 in link for details: Beckett injector intermittently not firing/ Taco rs504 no zones

2.Verify pressure and temperature gauges.Unfortunately many boiler gauges are inaccurate. Here is classic DIY link on subject:

Pressure Relief Valve leaking? Service your bladder type expansion tank!

3. Wire pilot light to circulator motor to see when powered on.


Final note. Part swapping has limites. Many heating problems are due to control issues so DIYer should learn basics.Bad or intermirttent electrial connection is common.

Last edited by doughess; 04-07-21 at 08:53 PM.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: