Christmas morning with hot water heater

[Davej]

Looks like my electric hot water heater has sprung a leak near the bottom next to the threaded hole for the drain. If I drained the thing and unscrewed the drain pipe I could probably reach in and daub something on the leak, but I'm guessing that wouldn't last and isn't worth the bother.

...So I want to replace this electric with a gas water heater. I'm guessing that means going to the county and pulling a permit so that an inspector can check my work? I have a gas furnace and I'm tired of having a $20 minimum gas bill every month all Spring, Summer and Fall for nothing.

[Joe]

This is a simple appliance replacement. In many jurisdictions that does not require a permit. If you ask, don't go overboard with details. It only confuses some bureaucrats. Start now collecting the right tools and materials, black iron pipe, pipe cutter, threading dies (Harbor Freight is decent, Ridgid if you intend to do it for a living). Also pipe dope (Teflon type), clips and anchors, street ells, tees, ells, unions, nipples, caps and plugs. Lay out a plan and figure out exactly what you will need, maybe add a plugged tee for a future back yard barbecue. Box store pipe is OK, but being Chinese it is not always perfectly round and will be harder to start a thread than American made. A small mounted pipe vise is cheap handy accessory, too. The plastic covered SS corrugated gas pipe is under fire now for problems, so avoid that until they get the situation resolved. HTH

Joe

[HeyBub]

You may not need a permit - it depends on how much your county wants to rip off its residents. Plus, if you start the bureacratic ball rolling, they may insist that the work be done by a licensed and blessed plumber. Best to call them and ask. Anonymously.

I don't think you'll need a bunch of pipe tools - dies, etc. Standard lengths from the box store should get you close enough to the new water heater such that a flexible pipe, three feet or so, can complete the connection.

I'm with you on saving money. I live in a duplex - converted to single family - and hooked the two gas supplies together. Then I had the gas company shut off service to one side. Saved $18.00/month.

[bob haller]

does your home have a convenient vent for the new gas water heater chimney? thats essential

[Davej]

This 50 yo house still has the chimney that was used for the original oil furnace so I am thinking I can use that for the hot water heater. The current gas furnace has the PVC pipe scheme so the old chimney has been unused and capped off. If I position the water heater next to the furnace I shouldn't need to add more than a minimal amount of gas pipe.

[Steve Barker]

There are also "direct vent" (two pvc pipes) and Power vent (one pvc pipe) units that will vent sideways through the wall with 2" pvc. But they are pricy.

[Steve Barker]

if that old 'chimney' is brick or pipe bigger than 5" diameter, you'll want to line the thing with a stainless or alumnimum liner to prevent condensation and insure proper draft. Just sticking a 3" line into an old chimney is done all the time, but is FAR from good.

[clare]

You will need a chimney insert (liner) for the flue to meet code - and for good reason. Put one in.

[clare]

Mine is 6 feet from the chimney. My daughter's is about 10 feet. Neither one is a forced vent.

[dpb]

It's not been an issue w/ an 8" square here in 60-some years.

[trader4]

Agree. The situation above usually comes up when an old furnace and water heater share the same chimney. The furnace is replaced with a direct vent one, leaving an orphaned water heater. The old chimney was sized for both. In the winter the furnace provided heat to keep the chimney hot enough so water vapor would not condense inside. With just the water heater, the large chimeny will now allow water to condense. Being acidic, over time it will destroy the chimney. Solution is the chimney liner. You can get away without one if the entire chimney is surrounded by heated home space, but that is usually not the case.

[trader4]

5" flue should be OK. I just ran a 4" liner for a water heater. That was because the flue was sized for a furnace and way oversize, probably abot 8 x 8". If it were 5" round I probably would have left it alone. Also depends on the climate. If it's FL I would not worry about condensation. If it's MN, then it's another thing.

Also, if poor draft were an issue, how do all the water heaters out there that are on larger shared chimneys with furnaces work in summer? Mine was on that big old chimney and worked fine for 27 years.

[Robert Macy]

Watch out code changes, chimney's may have to be lined before using for anything!

[ilbebauck]

Going the gas route will save you quite a bit of operational cost if you use alot of hot water. . If your old electric HWH was at least

10 years, it is time to get rid of it in any case before it REALLY springs a leak . If you want to go the cheap and quick route, you could go with another replacement electric HWH but put a 24 hour Time Clock on it so you allow the HWH to operate ONLY during times of your hot water needs, and off all other times. Youll notice a good saving going this route too.

[trader4]

Where's the evidence that a timer on a hot water heater saves enough in energy to make it worth it? How water tanks lose heat very slowly. Electric ones are the most well insulated because there is no flue running up the middle. If it made much difference, don't you think this would be std in electric water heaters by now?

If your utility has lower rates at night, then I've seen water heaters put on timers or seperate meters to take advantage of that and it can save $. It heats the water at night, when rates are lower. But a timer to turn off the water heater over night isn't going to save enough to make it worth the trouble.

[Steve Barker]

f*ck a bunch of code! They should be lined regardless.

[trader4]

How do you know what the specific code is where he lives? I would think a 5" flue is perfectly fine in many municipalities.

[trader4]

I live in NJ and remember those. Not sure if they still do it. But it was interesting that they had it way back then. Kind of an early version of the smart meters where they can have various rates now for different time perisods.

=A0Only problem was frequent power

e quoted text -

[bob haller]

a old unused chimney should be camera inspected by pros before reuse

[Ed Pawlowski]

I'd start here

1992 GAMA vent sizing tables for single-wall metal vent connectors attached to a tile lined masonry chimney uses Table 8. The result of those calculation using a 38,000 BTU water heater with a 3" draft hood and a 37,500 BTU boiler with a 4" draft hood connected to a 20' high chimney is to use a common flue with an area of 28 square inches or a

6" flue vs a 5" flue in the previous examples.

These tables also indicate that a 3" vent is not capable of venting the 38,000 BTU water heater. A 4" would be required. Also the flow area of the chimney must not be more that 7 times the area of the smallest vent area. Therefore, 7 x 7.065 = 49.455 vs 28, a 6 inch flue pipe is ok. The maximum size flue that could be used is 8 inch at

50.3.