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In the course of installing my new central heating, the installer discovered that my water heater is not firing up correctly -- the flame "rolls out" after a 2-3 second delay, and he says that's not safe.
So, it looks like I'll probably be replacing the water heater.
Any recommendations on what to replace it with? The current heater is 40 gal, I wouldn't mind going to 50 gal. It's natural gas-fired, and I'd prefer a "shorty" unit rather than full height.
Thanks for any suggestions.
your installer should have shut the gas off to your HW tank and red tagged it. Delayed ignition is dangerous. I would go with a Rinnah instant system.
Did he give a reason for roll-out?
I,m a plumber, not an HVAC professional, so I would replace with a 50 gal. tank. The shorty tanks sacrifice efficiency due to having a shorter distance that the water is exposed to before going out the flue.
I prefer the shorty's because they offer more vent rise to the chimney and therefore tell to spill less from the draft hood.
Any modern 40 gal/ 40,000 BTU water heater will do fine for a family of 4. Yes, a tall boy will be more efficient. Look at the chart. Its usually only 1% gain. I'd rather have the better vent rise. Its gotta flow uphill to the chimney breeching.
The main thing is to find out why the flame rollout. First, have the chimney inspected by a sweep. It could be blocked or simply oversized. Have a tech check the gas control. If you have low inlet gas pressure, it could cause a delayed ignition. If this is the case, it could do it on a new heater as well. ANSI stds allow for 4 seconds of delay btw the call for heat and full ignition of the burner.
Install a high quality CO alarm such as CO Experts or NCI. Very expensive and very worth it.
How old is the tank?If it is near ten or older junk it & don't bother trying to repair anything on it.The last time I checked bradford white had the best warranty.
He said he's not a water heater guy, but he thinks probably the burners may be dirty.Quote:
Originally posted by mike3
Did he give a reason for roll-out?
Additional info: the heater is about 10-12 yrs old, and there's a rusty "bathtub ring" around the basement perimeter,including the water heater, about 6-8" off the ground (with peeling paint on the heater below the ring).
Someone on the Breaktime forum suggested that if the burner assembly got wet whenever that flood occurred (it was before I bought the house), it could plug things up and might be the reason.
So, I *will* be getting a new water heater. The question is what brand/model?
Thanks,
Rebeccah
Yeah, vent rise is the issue here. I've got an 11' run to get to the vertical flue on the side of the hosue. Plus, the basement (only 6' ceiling) has flooded at least once to a significant depth (6-8") some time before I bought the house, so I'd like to be able to put the new water heater up on a concrete pedestal of some kind. In the last year and a half it's flooded about 1/2 inch, until I shimmed up the sump pump float so it would trigger *before* water gets over the side of the pit. The basement hasn't flooded since, but I don't trust it.Quote:
Originally posted by hearthman
I prefer the shorty's because they offer more vent rise to the chimney and therefore tell to spill less from the draft hood.
Any modern 40 gal/ 40,000 BTU water heater will do fine for a family of 4. Yes, a tall boy will be more efficient. Look at the chart. Its usually only 1% gain. I'd rather have the better vent rise. Its gotta flow uphill to the chimney breeching.
The water heater vent is being tied in to the new gas forced-air heating system vent, with a completely new type B flue. The old vent system was a KNOWN hazard, way too long horizontal run, reverse slope, improperly sized, single-wall and too close to combustibles... you get the idea.Quote:
The main thing is to find out why the flame rollout. First, have the chimney inspected by a sweep. It could be blocked or simply oversized.
If you're referring to the gas valve on the line on the side of the water heater, that was replaced because the old one was brass. The heating company said the brass ones fail prematurely and they routinely replace them whenever they do any work that involves the water heater.Quote:
Have a tech check the gas control. If you have low inlet gas pressure, it could cause a delayed ignition. If this is the case, it could do it on a new heater as well.
That's interesting. I didn't actually count the number of seconds to full ignition. It could have been anything between 3 and 5, really.Quote:
ANSI stds allow for 4 seconds of delay btw the call for heat and full ignition of the burner.
I have a plug-in CO sensor in the kitchen (almost directly above the water heater, actually), but it's about 8 years old and I have no idea how to test if it still works. Perhaps a new one would be in order. Should I put it in the basement/crawl space near the furnace and water heater, or in the house where people are?Quote:
Install a high quality CO alarm such as CO Experts or NCI. Very expensive and very worth it.
Thanks for your input, guys.
Rebeccah
I am in a similar situation as Rebecca. Although I don't have a problem right now, I might relocate my water heater next year, and at that point I will consider buying a new one.
So, as to not highjack the post and just try to contibute:
is there a real advantage to buying a tankless (gas) water heater vs. the regular ones? I know they tend to be more expensive, but not astronomically so.
Responding to the tankless water heater- I pride myself on being fairly open minded, I also embrace new technologies more easily than some. Whether a tankless or standard water heater will be of advantage depends on a few things. Do you need copious quantities of hot water? Yes- lean toward the tankless, No- forget the tankless. Are you aware that the tankless does not store quantities of hot water waiting to serve you? In other words, if you have a frequent need for just short bursts of hot water, such as frequent hand washing, you will discover a disadvantage to tankless. That is instead of waiting a few seconds for hot water, you may have to wait for 40 or so seconds. Not really that long a time frame, but when you are waiting, 30, 40 or more seconds may seem like forever. Venting exhaust gases from a tankless cannot be done by reusing the existing water heater flue. Stainless steel vent piping and it's associated fittings add up to serious change. Combustion air- your existing water heater may burn 35,000 or so Btu, so not a huge amount of combustion air may be required. A- you can pay a bonus for a direct vent model or B- you may need to provide outside air or other means to deliver adequate air to the tankless unit. Fuel line size: at 35MBtu your old water heater may have been fed by a 1/2" black pipe assembly. Under no circumstances will that pipe deliver almost 200 MBtu, so now you are faced with at least some repiping to do. Now for the one I will probably catch flak on- standby losses or as I call it, the Myth of stand by losses. I own a couple of rental homes, one has been vacant for 3 months, with the water heater left at it's normal setting. In those 3 months, 7 therms of Natural Gas have been consumed. Even at today's high gas prices, that comes to approximately $10 or approximately $40 per year. A tankless will have no standby losses, but at $40 per year, the investment will take a long time to recover. If you are going into new construction, these adjustments will be less exaggerated than retrofitting an existing home.
Someone may enter this thread and talk how their gas bill has reduced from $80 a month to $40 (just throwing out numbers). I don't doubt their word, but I'd have to see it with my own eyes and make certain all variables have been considered. Now, a wall mounted unit might be just what you need for easy installation at the new location.
In our home we have a condensing boiler and indirect water heater. Not only is it a virtually endless source of hot water for our family needs, but at 93% AFUE, I do not feel any indirect can match the performance IMHO. I am not against the tankless units, but when we talk to a customer about them, we go through a discovery phase where the pros and cons are discussed and they can make an informed decision without some BS hype as you see on TV or hear on radio ads. Some people believe what they want to believe and no amount of common sense will change their minds. Note, my closing signature's tongue in cheek approach to some attitudes- NOT MY ATTITUDE, however as I am extremely open minded, but pragmatic all the same. I use common sense, math and other practical means, not 'feelings' to form my opinions.
We have a commercial customer who is so pleased he can't say enough good about the tankless units we installed at his laundromat. We have a homeowner who likes theirs, but has some regrets all the same. No whopping savings in fuel consumption, less consumption- yes, but very little. Not as huge as Paul Harvey reports. Of course, that's not the brand we use, but that's not my point.
If you are tying your flue (natural draft)into a new furnace(induced draft) you should put baramertic dampers with spill switches in both flues to insure proper draft for both. Plus it's a saftey issue also!!
Midwest,
Thank you for the thorough response. A friend of mine who is an independent contractor (he mostly does framing, some plumbing, sheetrock, etc. but no water heaters) had told me something similar, but he said he didn't have all the info available so that's why I asked.
I hope this also helped Rebecca. Again, thank you.
Venting systems have strict code requirements so make sure your system meets these requirements before installing any type of damper in the venting system.