De-Rate a Burnham

Dick_3

I'd like to de-rate a Burnham Independence gas fired steam boiler
from a rated DOE capacity of 144M to 106M. Lower manifold psi or change orifices?

Thanks in advance.

<A HREF="http://www.heatinghelp.com/getListed.cfm?id=363&Step=30">To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"</A>

hr

Check with the factory

for the correct, and safe method. Quite a bit liability involved when you start field modifing equipment. Best to get the approved method, in writing, from the manufacture.

hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

bob young

downsize

i tried to get that from crown & they flat out refused.

[Deleted User]

Can't says I blame them...

It messes with their equipments ability to make steam. Everything in that box was made for a specific rating. Substantial differences CAN result in either equipment failures or performance failures, or both.

THAT is why they don't want you messing with it.

Can't say as I blame them...

Why do you feel the need to turn one down? Matching EDR or heat loss... Just wonderin'...

ME

Robert O'Connor_11

What about that debate?

EDR vs Heatloss.

I'm still going with EDR for replacement steamers. However, I see room to play with the pickup factor and go with "heat loss" as a method of sizing replacement steamers..

Boiler Pro Dave , anyone.. Any new experiences or data?

All the best

Robert

ME

PS : With the volume of lawyers in our marketplace I am compelled to agree with HR's advice. Only by the book ...

Jacob Myron_18

Derate a boiler.

Jacob Myron_18

Derate a boiler.

Jacob Myron_18

Derate a boiler.

Jacob Myron_18

Derate a boiler.

Jacob Myron_18

Derate a boiler.

Jacob Myron_18

Derate a boiler?

What do you think you will gain by derating the toy you call a boiler by 38,000 btuh.

You need to remember that the boiler will burn the 144,000 Btus in one hour if the boiler runs an hour.

If your house uses lets say 100,000 BTUh and the extra capacity of the boiler is used heating the house a bit sooner the boiler will only run proportionatley the heating need.

Simply said if you reach the set steam pressure sooner the boiler operate less.


Jake

Dick_3

Keep in mind this is a steam boiler. I have a calulated connected load of 79M and used a .33 pickup factor to get a total load of 106M. The existing boiler is rated at 144M DOE.

The customer, which is a lawyer, requested to have several problems corrected - one of which is a short cycling boiler. The air vents are new and operational, water clean, psi low, and all rads are heating 100%.

Just wishfull thinking, as far as, de-rating the boiler. The manufacturer recommends lowering the manifold psi no more than 10%. I can appreciate the liability issues.

The installing contractor re-piped the new boiler 3 times before getting the near boiler piping correct one year ago.

Customer still is not satisfied with the operation. Quess we'll quote a new boiler to solve the short cycling problem. Anybody want a deal on a 144M steamer-one year old? Any other ideas?

Thanks, in advance.



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mark Hunt

De-rate that boiler at your own risk


I do not know you and I do not know what skill level you are at, but if you mess around with the firing capacity of that boiler you own it.

Can you perform a combustion analysis after you are done?

Can you document your findings??

In a court of law, the lawyer would eat you alive if you can't.

So before you start changing things, be sure you can document that you have changed things for the better. If you can't do that, leave the damn boiler as it sits.

Mark H

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Dick_5

Why not plug several orifices in the burner gas manifold?

Long Beach Ed

I've done it.

I've derated several of my own boilers by about 15%, but I own them, own the buildings and have the proper license. The liability is certainly a factor and the advice you have been offered is really good.

Also remember, what are you earning for taking on the liability and risk?

There was a time that one manufacturer would say that 20% is fine. Of course you don't want to run the risk of "simmering" the water and wasting fuel.

I really wouldn't bet that what you want to do will solve the problem. A pick up factor of 50% isn't uncommon with some steam and God knows we've seen thousands of systems with Grosssly oversized beasts that heat just fine.

If the thing heats all the radiators, builds pressure, shuts down then cycles on presssure, you are fine. If it's cycling without heating all the radiators, you have a problem. Sure the mains are vented well?

Long Beach Ed