Boiler Temp

[mstrlucky74]

Not sure whether these are 277/480. Trying to determine load in amps for 135 HP and 290HP. Thank.

 

[Ingenieur]

pretty sure that is boiler hp, not motor/pump hp

https://www.engineeringtoolbox.com/boiler-horsepower-d_1061.html

 

[drcampbell]

It does say "BOILER HORSE POWER" at the top of each column.
One boiler horsepower is about 9.8 kW.

It's about 13x more power than a mechanical horsepower because in days of old, when it was defined, it represented the amount of heat required to get a mechanical horsepower out of a steam engine, which achieved about 7% efficiency at the time.

One of the nice thing about standards (such as horsepower) is that there are so many different ones to choose from.

To eliminate ambiguity, (and 80% of errors) follow the guidelines.
Guide for the Use of the International System of Units (SI)
National Institute of Standards and Technology
Special Publicatio n 811
https://physics.nist.gov/cuu/pdf/sp811.pdf

 

[Jraef]

It should be noted though that Boiler HP only relates to electrical loads if they are electrically heated boilers. I would find it unusual to see that much boiler load done electrically. It’s more likely has or oil fed boilers.

 

[gadfly56]

It should be noted though that Boiler HP only relates to electrical loads if they are electrically heated boilers. I would find it unusual to see that much boiler load done electrically. It’s more likely has or oil fed boilers.

I'm going to assume you meant "gas or oil", and you'd be right. For whatever reason, stationary heating plants are measured this way. At certain size breaks, you need a black, red, blue, or gold seal operator on premises 24/7.

 

[mstrlucky74]

A few points. So boilers can be "fed" either, electrically, via oil or gas? This is their so called "source"?

Each of these boilers take care of a high rise apartment building with about 600 apartments. They definitely need electric. We were told they need temp power.

I'm still not clear on how to arrive at the load in amps?

Sorry and thanks/

 

[gadfly56]

A few points. So boilers can be "fed" either, electrically, via oil or gas? This is their so called "source"?

Each of these boilers take care of a high rise apartment building with about 600 apartments. They definitely need electric. We were told they need temp power.

I'm still not clear on how to arrive at the load in amps?

Sorry and thanks/

They may need electric, but that chart isn't going to help you figure out how much unless you're somewhere that they charge only a penny a kilowatt-hour. As Jraef said, the BHP is related to the firing rate of the fossil fuel supply, not the juice needed to run the blowers, pumps, controllers, and what-not. In other words, they gave you a bushel of apples and said "Make orange juice".

 

[Ingenieur]

1st you need to know their fuel type (likely gas)
if electric you are talking >5 mva (I'ld be VERY surprised if electric)

2nd, visit the site, they are likely talking about control power and circ pump power

get as-builts

I would strongly suggest you sit down with the mech engineer/contractor to discuss scope

 

[mstrlucky74]

Thanks a lot guys. I will dig into the mechanicals a little more and see what I can come up with.

 

[mstrlucky74]

1st you need to know their fuel type (likely gas)
if electric you are talking >5 mva (I'ld be VERY surprised if electric)

2nd, visit the site, they are likely talking about control power and circ pump power

get as-builts

I would strongly suggest you sit down with the mech engineer/contractor to discuss scope

What do you mean "if electric"? The mechanical said we need to run temp power to them. They must require electric.

 

[USMC1302]

What they're saying is, yes they require electric, likely for controls, burner, combustion air dampers, condensate pumps, etc. but not as the primary source of energy to operate. Likely gas or fuel oil. Where did you get this information? They're steam boilers. It also has two columns. One for domestic hot water, the other lists domestic hot water and heat. Which is it? You haven't been given complete info to determine loads.

 

[Ingenieur]

What do you mean "if electric"? The mechanical said we need to run temp power to them. They must require electric.

if the HEATING source is electric
the difference is a few 20 a ckts per boiler vs a 400 A (480 vac)

 

[mstrlucky74]

Hey guys can't thank you enough. So here are some RFI questions I came across.

Thought the temp electric they are requesting was the primary "source" for the boiler to operate.

BTW the mech emailed me and stated below. He obviously has a typo regarding amps....I think since there are 8 temp boilers he means 18 200a panels.
Yes each temp boiler will require temp power. Mechanical says 1800/200 Amp temp panels will be suffice.

 

[jumper]

Hey guys can't thank you enough. So here are some RFI questions I came across.

Thought the temp electric they are requesting was the primary "source" for the boiler to operate.

BTW the mech emailed me and stated below. He obviously has a typo regarding amps....I think since there are 8 temp boilers he means 18 200a panels.
Yes each temp boiler will require temp power. Mechanical says 1800/200 Amp temp panels will be suffice.

8 temp boilers.

I would be more inclined towards 8 100A or 200A panels would work.

One panel per boiler. 100A is probably sufficient but 200A panels are more common.

 

[mstrlucky74]

8 temp boilers.

I would be more inclined towards 8 100A or 200A panels would work.

One panel per boiler. 100A is probably sufficient but 200A panels are more common.

There are 18 temp boilers. 100%

 

[jumper]

There are 18 temp boilers. 100%

Okay. There are 2 typos in #13 then. His and yours.

 

[mstrlucky74]

Okay. There are 2 typos in #13 then. His and yours.

:dunce::lol: You are correct.

 

[junkhound]

One boiler horsepower is about 9.8 kW.

It's about 13x more power than a mechanical horsepower because in days of old, when it was defined, it represented the amount of heat required to get a mechanical horsepower out of a steam engine, which achieved about 7% efficiency at the time.

Dang, interesting tidbit! Thanks for the history.
How'd I get to be as old as I am without realizing the 7% number.

What does a combined cycle "boiler' get these days in an up to date NG power plant, close to 55% or more, and 80% co-gen? And even coal plants pushing 50% .

http://cornerstonemag.net/setting-the-benchmark-the-worlds-most-efficient-coal-fired-power-plants/