In the USA - we prefer to use gas heaters because they're less expensive to operate. I just discovered that our brand spanking new gas water heater may have been (probably is) a mistake.

The gas in our ancient apartment building is kind of dirty - leaves scum and residue on the gas stove and sometimes smells like burning plastic.

Our brand spanking new gas water heater failed after only 90 days on the job - seems the residue from the gas clogged up the heat exchange pipes AND was probably also wreaking havoc with the circuit board. The "workman" emptied out about a cup of multi-colored ash (really pretty actually) from the vent and heat exchanger assembly and surrounding areas. So - obviously this will require the eventual replacement of the heat exchanger for a "cleaner" heat exchanger (about ¥200).

So - for those wise ones out there - do you have any probs to report with your electric water heaters - aside from running out of hot water because the tank's too small? We're thinking of adding solar heaters to supplement the gas heater and help cut the gas bill. Our recent gas bill was 5-10x that of our neighbors - used to be only 3x which was livable (big family), but 5-10x is now totally out of control.

I used to live in a seventh floor apartment equipped with a brand spanking new Haier electric tank heater. Unfortunately the municipal water supply's pressure would often dip so low that only a tiny trickle would flow out of the shower head. We never found out if a pressure booster would have worked because the landlord was convinced that it would not and refused to help us get one installed.

I now have a gas flash-style heater with a pressure booster attached and I'm much happier with it. I live alone, but only use maybe 20 to 50 kuai a month of gas for cooking and showering, but I have solar backup for sunny days.

Sorry to hear about your dirty gas problem. I had a newly installed 80L gas heater in Jiang Dong Hua Cheng that worked fine. I also cooked with gas and the cost was about 22 yuan a month.

Electricity seemed high and I often wondered about that. It stayed about the same even when I was out of town for nearly a month.

Moved six months ago and now have an electric water heater, still cook with gas. Oddly, the electric bill is lower even though I am now heating water.

Hard to figure out what is going on.

The problem with the gas here is that it is of poor quality. While at first the gas heater pumped out gallons of hot water, over time the volume became less and less, until even a trickle is ice cold. I've had to have the repair guy around several times, and in one case had to replace a part which cost 300RMB- all due to the dirty gas.

Of course, this problem will only be an issue for those who wash frequently...

My experience

Electric
The electric water heaters are fine, if ugly. You need to make sure you get one big enough for each bathroom. Get separate tank for kitchen too.
If people are a bit thoughtful about water use there is no problem.I.E. Water on, wet body. Water off, soap body. Water on, rinse body. No luxuriating.
The good ones keep the water hot for several days, and they have a speed heat setting (double heaters).

I can see a problem with a pressure booster before the tank, it creates negative pressure behind it that may cause problems for other residences, and may even cause an airlock. They may not be permitted by the water company. I had the same issue in the UK for mains fed water, not permitted.

Solar,
Good solar heat exchangers can reach temperatures of 120 degrees, before heat is exchanged. You get what you pay for.
We have solar heating and it is crap. The biggest issue is that water feeds down into a hot water tank. The tank has a heating element to boost the temperature. However, the thermal lagging seems to have little effect, possible becuase the water is circulating in poorly insulated pipes. The water can drop from 50* to 20* in less than three hours. To make matters worse, the heater cannot be timed, and so the water is on 24/7. We tried to heat the water before bed, but in the morning the water is down to 20*.

I think to get a high quality complete system is going to cost you bigger money. And you need to ensure than having bought the best pipe, the installer does not swap it out for cheap stuff when you are not looking.

Gas
We had gas installed in Shanghai and it was expensive to run. Part of the problem is that even the factory engineers could not get the thermostat to work on the timer setting. And so the water was on 24/7, and the central heating we switched on on demand.
I have not experience with Kunming gas.

My gas experience is based on the "instant on" gas heating systems, not a storage type. They typically cost about 800rmb up, plus installation, and ongoing repairs.

Sounds odd Chingis.

Gas blockage would not stop water flow that I can see. Unless someone can enlighten me.

The nozzles on the taps has a filter that clogs. This reduces water flow. If flow is too low the heater will not come on due to a safety mechanism.

We cleaned our nozzles with vinegar (2 day soak), although a propriety drain cleaner may work better. Having said that, I have now taken our nozzle filter off. The only differences are that water comes out faster, but not in a nice jet as before.

Sorry, what I mean is that as the water heating becomes less efficient due to the heating component becoming covered in crud from the poor gas, the only way to try to maintain water temperature is turn down the flow, until it becomes a dribble.

I have a large electric water heater. I built a timer for it using a high amp contactor and a digital timer. It has worked perfectly for over 3 years now. I can program 6 on/off times which is more than enough. It also has separate weekend times. When I go out of town, I simply have to go to manual mode and push off. Cost me about 100 RMB to build. I save a good bit on my electric bill.
BTW, I also put in a whole house water filter system. See post on water filter. I wanted to boost my pressure which always sucked. But with a filter system, it is even worse. So I installed a pressure booster. Now I have 50 psi, plenty of hot water, and a good functional water filtration system. My condo people also said a booster will not help me. (I live on the top floor). I installed it anyway, and it is 100% better and working fine. People below me?? Well who cares. You do what ya gotta do. I haven't heard any complaints, but then again they don't know I got a pump.

Dantheman, I recommend you get a pump. But don't buy the ones you see around in the stores. They are crap. Go to the builders market and get a commercial booster, preferably imported. I paid like 1800 RMB for mine.

Everyone - thanks much for the feedback and inputs. I installed a shutoff valve on the gas heater (flash or on-demand) while trying to salvage the previous water heater (lost cause) which we gradually shunt as the heater becomes less effective as the days roll by. The stupid crappy lying...blah blah blah handyman tried to tell me I need to restrict the water flow to get hot water - rendering the shower less effective than spitting. I countered with "it worked fine when we bought it" to which he countered "you'll need to replace the heat exchanger whatchamacallit thingy for ¥200+" and since the thing still sorta works - he won't replace it under the warranty as HE has to pay for the part out of pocket (to which my BS filter kicked in and didn't hear the rest of his spiel). However his comment about responsibility for the prob kind of makes sense as dirty gas is not the mfg's problem - it's my prob - thank you very much Kunming Gas & Electric.

GAS "ON-DEMAND/FLASH" HEATERS
Dirty gas - requires monthly maintenance eventually resulting in obliteration of the heat exchange and temperature monitoring sensors.

Additional hidden cost ¥200-300+ after the warranty runs out.

ELECTRIC HEATERS
Water pressure problem.

Resolved by installing Pressure pump and generally screwing the neighbor's water pressure - but who would know it's you eh? I see an April fool's prank in there...wait for the neighbors to start their shower, then fire up the bath tub. Gyahahahaha...(one too many manga)

Big ol' hunkin piece of machinery on the wall (and if one follows the guidelines) in both the bathroom AND the kitchen. One more thing to fall off the wall during an earthquake.

SOLAR
Buyer beware - and especially beware the mom n pop "solar heaters are us" joints.
Maybe better to import foreign (HK?) stuff.

GAS BILL
FYI - we're burning thru about ¥200-300 a month on the gas, while our neighbors are doing about ¥20-30. My six-month gas bill was ¥1600-ish - the neighbors - about ¥200-300. Truthfully, I suspect someone in the building tapped our gas main (or EVERYONE in the building) - but I checked their gas bill (the joys of china - everyone's bill is posted on the public bulletin board) and they all look pseudo normal - except for me, the gas hog. So either our water heater's burning through gas like an oil refinery - or we have a leak. Our electric bill is only 3x the average neighbor's bill, so really not sure what to make of the sudden hike in our gas bill. Our water bill - if anyone cares - was about ¥1500 (over 2-3 months?). Too many women in the house taking luxurious hot baths and showers, I suppose. I live and work primarily to support the water, gas, and electric companies and their employees in Yunnan, not to mention paying our rather dim-witted but generally pleasant ayi - who earns more than most college grads. If you think I'm being mean - the ayi couldn't help resolve my son's grade 2 math homework...and her handwriting and reading abilities are also sub grade 2 - but she's reliable and pleasant (better darn well be pleasant for what I'm paying her).

HANDYMAN
I laughed at/with him and politely told him to get lost until next month, when the water temperature once again drops below 38 C (normal temperature for giving babies baths), despite maximum gas flame and shunting the water to a trickle. Sometimes, I really hate living in Kunming.

UPGRADES
Don't wanna drop another penny into this place and I'm EXTREMELY wary of buying local solar heaters - legitimate bubble gum, rubber band, and duct tape construction fears. The apartment is ancient and we wanna move (buy) a more modern apartment with a BIG pseudo-park area for the kids to play, ride bikes, and generally scream and yell to their heart's content outside, without driving me nutso. Not to mention get away from the bars, KTVs, and generally crappy stores with their crappy blah blah blah whine whine whine - although this place is great for the young 'uns - aside from the midnite curfew on the manually operated gate lorded over by the entrenched security guard and her immense family (all squeezed into a roughly 5x5 meter room, designed for a single occupant.

I'm guessing the NEWER areas, such as chenggong and maybe dianchi have newer piping etc - which in my dream equates to cleaner gas, etc. I know it's just an illusion - but permit me to fantasize.

BUCKO
Thanks for the home fixit ideas. If you make it this far down the blog - which builder's market do you loiter? I'm kind of browned off at B&Q. Guess I'll go do a google search on gas filters - see if I can fix the problem at the source, without blowing up the apartment. When I look at the gas and water piping and the electrical wiring in the house - the word "amateur" springs to mind...amidst other choice non-printable invectives.

NEXT BLOG - REPLACING THE BATH TUB ODYSSEY
Got a couple of new things on the list - one is replacing the jacuzzi bath tub - the jacuzzi part perished long ago and the pipes have some kind of fungus that floats out occasionally when the kids are bathing - replacing the bathtub is seriously high on the fixit list. I'm just dying to find out what kind of insanity awaits with that seemingly simple task. I think I'll insert/install a water shut-off valve INSIDE the house prior to that event...just in case. And yes, this place is seriously old - the water shut-off valve is outside at the common octopus rig - where one small hose feeds into something like 12 equally sized hoses - god forbid we should all try to shower at the same time.

At least last year's cockroach infestation has abated - I think we genocided them with the chinese bug spray - either that or they moved to greener pastures as I make the ayi hyper-clean the kitchen daily AND check to make sure the work is done...daily - coincides with my making the kids' breakfast every morning...

OPTIONAL - REPLACING THE WASHING MACHINE
I'm sure the water in this place has problems also - however we'll see how that affects those combo washer/dryer all-in-one units. The gas heater worked 90 days before the hidden probs kicked in. I'm quivering with excitement over what new and bizarre things to expect with the washing machine, the BS filters are hair triggered and rearing to go!