Boiler oversized

mtlight

Post Hurricaine Sandy finding boilers quickly was difficult. I purchased a WM EG45(392 sq ft steam) rather than my old EG40(325 sq ft of steam) My connected load is 270 sq ft one pipe system. . As you can see, the smaller boiler put me closer to my connected load than the larger one. I still had some additional room for a radiator which i need for a kitchen remodel. since my install, I changed two main vents. Steam seems to move efficiently to the end of the main withing a minute or so of the steam beginning. I added a low pressure gauge. The boiler was skimmed 4 times and the water line seems pretty steady. My main and takeoffs were all insulated. Here are few issues that I could use some advice on:

From a cold start it takes the boiler about 40 min to get up to 2psi where the ptrol cuts out the boiler and the cuts back in between .25-.50 psi. once the pressure is reached from the cold start, the rads are almost hot all the way across but usually can not make a call of 3-4 degrees without cycling. Usually 3-4 cycles of 3min run then 2min off until the thrermo call is reached. Looking at the specs of these two boiler, it appears that the boiler size, weight, sections and controls are all the same expept for the manifold tray and maybe a part to the flu.

Question: If i change the manifold and the tray from a 6 burner to a 5 burner(which is what the user manual shows as the difference) with the flue part also changed, am i downsizing this boiler correctly to my prior size boiler (325 Sq ft). I have done a lot of the boiler work myself and im willing to do do this(in the summer lol) To me it logical and not too labor intensive. Am I missing something? suggestions? Thanks in advance

Mike

Mike Kusiak_2

Is it worth it?

While your boiler is slightly oversized, I don't think it is a good idea to do what you seem to be proposing. Are you planning on removing one burner but not removing the corresponding cast iron boiler section?



If you do this, the section without the burner will be at a different temperature than the remaining ones, resulting in cyclical mechanical stresses. In addition, cool excess air will still flow through that section with no burner, reducing efficiency.



A better idea might be to downfire the burners 10% by either changing orifices or reducing manifold pressure. It is also easily reversible in the case if you add the additional radiator and need extra output. This is a simple procedure, but should be done by someone with a combustion analyzer to insure safe and efficient operation.

JStar

Boiler

He wants to replace the entire burner tray, which sounds like the best idea. The sections are the same.



HOWEVER! I would highly advise that you get a professional to, at least, inspect the work before firing it up. Hire somebody with a combustion analyzer, who knows how to use it, to make the final adjustments

mtlight

Thanks

As JStar said, its the same boiler sections in both boilers except as per boiler parts manual the only difference is a 5 burner manifold as compared to a 6 burner manifold. I stripped and put the burner in initially with a plumber, so i know what it entails to undo a few things. Thinking about it now. Maybe a summer job

mtlight

Adjustments

Jstar If i remove the regulator and place it on the new burner tray, what adjustments will have to be made. I see it as just moving the regulator to a smaller burner tray which when bought from the manufacturer uses the same regulator? thanks in advance

JStar

Burners

I don't know what adjustments will need to be made. That's why it needs to be tested.



Take the time to do it right the first time and save yourself the heartache of hurting or killing somebody in the house. It's not worth neglecting.