DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   HVAC (
-   -   Hot water tank flue has hot exhaust coming out (

Lynnie59 07-04-2012 09:43 PM

Hot water tank flue has hot exhaust coming out
We can feel hot air coming out of the flue on our water tank. This happened last year, my husband thought it might be a air flow issue, so thought to open the window in the small laundry room where the tank is located. This seemed to take care of the problem.
Today, he noticed the same problem. We are wondering if it has something to do with air flow/house being sealed off too tightly?
Can a dirty coil on our central air unit cause this issue?
We lost our power 3 days ago, so couldn't run our central air, had a 500 sq ft addition we slept in while running a portable air cond unit, so had the room sealed from the main house (900 sq ft) with a blanket in the connecting doorway entry.
We got our power back, turned on the cen air unit and husband noticed this issue with the tank flue now.
Are there any things he can check? What are the reasons this happens? It has only happened once before, and only during the COOLING season, never the Winter months with the furnace running.????please help soon!

wctekkk 07-04-2012 09:49 PM

your water heater flue?

Lynnie59 07-04-2012 09:52 PM

yes, hot water tank flue
Yes, this is the issue..

wctekkk 07-04-2012 10:24 PM

ok if hot air is not coming out a section of vent or seam or under bonnet and the water heater is coming on when needed shutting off when reach desired temp setting. my diagnoses no mechanical failures.NOTE i'm not there carbon dioxide is no joke please call a licence plumber.

wctekkk 07-04-2012 10:27 PM

? is there multiple appliances tying into a common vent?

Lynnie59 07-04-2012 10:36 PM

hot water tank flue air leakage
Yes, there are multiples on same vent: furnace, cen air, and water tank. Now that the window in this small 8x8 room, window is open about 3" the air is NOT coming out the flue at this point. This is the same thing hubby did last year when this happened and it solved it.
What are the reasons for the hot air to come out of the flue like this?

Thanks for your input!

wctekkk 07-04-2012 10:51 PM

I'm real sorry were exactly is air escaping from sounds like your a/c and or all may not have enough combustion air I'M NOT a HVAC tech just a plumber i'll help you the best i can maybe check your air filter.

Lynnie59 07-04-2012 10:58 PM

Air escaping from water tank flue
The air//exhaust is escaping from the top of the flue opening where it's usually not happening. Hubby checks it, and just noticed it's doing this again, but stopped once the window was opened--ventilation? air circulation issue?
Our laundry room is very small, and has one door that is always closed, and another louvered door adjacent to it leading to the kitchen.
Thanks for trying to help us, just don't know WHY this is happening
We asked our air cond guy recently, he just said it was ODD..yes, but, we need to find out why it's happening, right?
So, in your experience, you haven't dealt with this issue with a customer ever?

wctekkk 07-04-2012 11:18 PM

i know what's required for a w/h combustion air but not for a/c /furnace i run the gas, cond, pan drain only to a/c /furnace there is a formula

wctekkk 07-04-2012 11:19 PM

?...what's ODD..

wctekkk 07-04-2012 11:24 PM

has anybody looked were vent terminates for possible obstruction i should have ask a long time ago what type of w/h- gas,lp,power vent direct vent?

Lynnie59 07-05-2012 02:00 PM

water heater flue leaking air
Yes, hubby checked for obstructions and there are none. It's a direct vent, gas w/heater.

oh'mike 07-05-2012 02:47 PM

Moved this to HVAC---you have a negative air pressure issue---

HVAC techs deal with this on a daily basis.---Mike----

beenthere 07-05-2012 06:35 PM

Do you know what the inside dimensions are of your chimney. Does the down draft occur only when the water heater's main burner is on, or just when the pilot is on. Or all the time when the window isn't open.

Can you post pics of the water heater flue pipe as it runs to the chimney.

hvac instructor 07-05-2012 07:08 PM

is the return on the furnace open or is there duct work going to it.
the return has to be closed as a open return will pull air into it when on and can cause a negitive air pressure in the room which will suck the flue gas out of the water tank

All times are GMT -5. The time now is 04:05 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1