Venting issue

[Blain Plantz]

First I referred the buyer to a licensed HVAC professional. This set up looks odd. As you can see the the water heater and the furnace are connected via connector that then goes down to an old chimney connection. It looks like the chimney has metal ducting installed but the chimney is too high above the roof for me to see the top. I fired up the furnace and was able to determine a healthy draw at the water heater side. did I spend my buyer's money for nothing or would you guys call this out I get a little skittish when it comes to CO.

thanks
Blain

[John Arnold]

"looks odd" is a major understatement.
That is completely and utterly wrong.

[Roger Hankey]

First I referred the buyer to a licensed HVAC professional. This set up looks odd. As you can see the the water heater and the furnace are connected via connector that then goes down to an old chimney connection. It looks like the chimney has metal ducting installed but the chimney is too high above the roof for me to see the top. I fired up the furnace and was able to determine a healthy draw at the water heater side. did I spend my buyer's money for nothing or would you guys call this out I get a little skittish when it comes to CO.

thanks
Blain

You did NOT waste your client's money. This is an improper installation. Gas appliance vent connectors, whether from the water heater, furnace, or other appliance need a continuous uphill slope, with as smooth a path to the vertical section as possible. The installation you showed does neither. Just because you were able to establish a draft under the conditions you encountered does not mean that this will be the case under all situations. See the attached image from Carson-Dunlop's Illustrated Home. I hope you checked the rest of the HVAC installation carefully, as this is clearly the work of an unqualified individual. One place to check is the top of the water heater for signs of back draft or back spillage. (melted plastic disks around the water pipes).

The system is wrong whether or not CO is being produced. Spillage of combustion products; whether from leak vents, blocked vents, or back drafting has the potential to introduce excessive levels of CO2 into the mechanical room. CO2 is heavier than air and under certain conditions, particularly if there is no combustion air duct, the water heater and/or furnace can begin to make CO due to the displacement of air by the CO2.

Best wishes.

[Blain Plantz]

thanks for the information

[Nick Ostrowski]

Wow!!! Whoever installed that should be arrested. Brutal!

[Bob Harper]

I'll ditto Roger and add a few:
Common vent appears to exceed x7 rule on WH
Tin tape on connector
red RTV silicone at breaching
lack of connector support.
Is that mambo sized return slinky properly sealed along with all the rest of the ducts?
Makeup air?
Listed chimney liner properly sized? You should be able to see the listed termination regardless of height.
Clearances to combustibles off connector.
Does that galv. steel TPR drain have threads on the end or clean cut?
Chimney cleanout within 12" of breaching?

Even when done per code, this is a dangerous setup. If the common vent blocks or restricts, the furnace will continue to fire venting out the WH's draft hood without tripping any of the three safeties in the furnace. NCI course teaches you how to correct this.

[James Duffin]

Wow!!! Whoever installed that should be arrested. Brutal!

I agree....that is a real mess!