let's talk numbers

Timco

water heater reading: Eff:82.3, Excess air:55.2, stack temp:320, pri temp:74, delta:---, O2:8.0, CO2:7.3, CO:4, CO air free:6, draft:-0.01wc..........and now the boiler Eff:81.8, Ex air:72.7, stack temp:318, pri temp:82.1, delta:----, O2:9.4, CO2:6.5, CO:9, CO airfree:16, draft:0.00wc. Boiler is WM CGA gold, and water heater is a GE....both nat gas. Took these numbers after stack temp leveled off.

Am I getting these readings correct? First tests with the new 125 pro. I have a lot of reading to do...and classes scheduled.

T

Timco

Anyone? Are these numbers in the ballpark? One has to start somewhere, and I am doing this by the book...

T

Glenn Harrison_2

IMO

Water heater looks OK. Boiler apears a little off. O2 should be 7 to 9%. also, you should always have a negative .01 to -.02 draft at least. That .00 draft is no good.

If you want some readily availble reading material on combustion testing, check out the Bacharach Traingin Room at:

http://bacharach-training.com/

Timco

Sooo..

If I have low draft, that would mean I could use some extra combustion air, as there are only 2 45* bends in a very short distance for the vent...but the high O2 says I have excess combustion air/draft??? Can the shutters be adjusted to lower the primary air and get some combustion air in there? The furnace room is open to the entire basement of a 1910 house...pleanty of leaks.

Thanks,

T

Mark Hunt

Combustion is occurring


and your CO numbers are not high. That would put "combustion air" out of the running.

What is the base pressure of the CAZ?

Mark H

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

Timco

CAZ? That's a new term for me...Still learnin'.

T

Steve_35

You might look to your chimney for the draft.

Any leakage in the chimney? Clean out doors. Are the vent connectors properly sized?

Timco

175,000 BTU unit with 6" all the way...just less than 5 feet or so, with one 90 and one 45. Chimney was re-tuck pointed a few years ago but has no liner.

T

Steve_35

An unlined chimney

doesn't meet the National Fuel Gas Code.

There is an exemption if you replace existing equipment with equipment that is "similar type, input rating and efficiency." In other words you need to have the chimney lined.

The inner area of the chimney can't exceed 7 times the area of the smallest draft hood or flue collar connected to it. If you have a 3" draft hood on a WH the max flue size is 7x7 or 49 sq in.

Although I can't put my finger on it at the moment I don't believe you can use an unlined exterior chimney if you follow the NFGC (NFPA 54).

If you have poor draft the chimney is the likely culprit.

Darin Cook_2

It is

Combustion appliance zone.

Darin

Timco

Will the fyrite pro 125 measure this? I ordered the optional differential pressure kit, but it will be a week.

T

Timco

Would the liner be the same single wall galvi as the boiler vent? Would the boiler 6" tie into a T in the chimney? What would the ideal cap be? Here in SLC I don't think a single chimney is lined except for when a fireplace insert is installed (enclosed pellet burner type)AND a permit was pulled.....

T

Steve_35

It depends

Is the chimney interior or exterior? If exterior, B-vent in an unused chimney flue meets NFPA 54.

We generally turn lining over the another company and they typically install aluminum or SS flexible liners. A single wall galv pipe may be acceptable if the chimney is interior but I haven't looked that up.

NYS WC is hell on contractors that have employees use ladders or get on roofs.

You may want to go to www.nfpa.org. You can download the latest books in pdf format. I think they're around $30 or so. Nothing beats having the knowledge and being able to back up your statements when the HO says, "How come none of the other contractors mentioned that?" "I don't know, ma'am. I guess they don't know or don't care."

Rudy

Give me a call

Certainly keep posting here - alot of valuable info for everybody.

Also, feel free to give me a call (it's part of what I do for Bacharach)

412-576-1350