Outdoor water heater (tankless)

I have installed a tankless water heater on the outside of my house, with an 8-foot stainless vent running up to above the roof line (this was necessary, since the unit was installed within 4 feet of a window.) Is there any need to attach a condensation drain at the bottom of the vent pipe (just above the unit)? Living in S. California, I am mostly concerned about overnight dew condensation leaking into the heating unit.

By the way, despite all the tankless naysayers out there, this unit is AMAZING! About the size of a desktop computer attached to the wall, I have freed up precious floor space in my house and have nothing but praise for how well it functions and conserves energy.

-Halogen25

Hopefully, it never gets below freezing or it doesn't rain in South Carolina...is the thing sheltered from rain and snow?

But, if you are concerned with gases getting into your window, since the condensate drain could leak them (since it is normally connected to it or how would the condensate from the combustion get out anyways), then yes, it should have a trap on it. You'd want to direct it so that it doesn't drain all over the unit, too or down the wall of the house.

Did the local inspector pass this installation?

Yep, if you live in South Vermont......it is probably gonna rain. I would make sure there is a tee instead of a 90 for the turn of direction vertically. Use a push-in cap at the bottom of the tee, drill a hole to mfg. size to allow condensation to drip out. Not a large hole though. I'm basically following the idea of PowerVent water heaters without the use of plastic components. And anyone that reads this, I always convince customers to go ahead and either leave those condensation drip lines in or install one on any powervent because it is a great prevention of condensation dripping back into the blower.


By the way, I am one of them tankless naysayers, and I have to say that I have a house that I don't have to worry about having 4 square feet of space. I have more than I'll ever need, I have sprawling square footage. I agree that in specific situations they work well, but it will have its place like bidets do in residential homes. About 1 out of every 100 homes have them and most likely it will stay that way. At least you don't need a 1-800 number or a specific person to fix a bidet.

southern california

Ithink he said he was in southern california....

the thing would work ok in any desert area


I am also a nay sayer,


so lets give it a year or two and see if you are
still satisfied...

once the honey moon is over....

tankless

If you just installed it, how do you know it is saving you energy?

RUGGED said:

By the way, I am one of them tankless naysayers, and I have to say that I have a house that I don't have to worry about having 4 square feet of space. I have more than I'll ever need, I have sprawling square footage. I agree that in specific situations they work well, but it will have its place like bidets do in residential homes. About 1 out of every 100 homes have them and most likely it will stay that way. At least you don't need a 1-800 number or a specific person to fix a bidet.

Click to expand...

Any idea what a square foot costs in San Diego??

hj said:

If you just installed it, how do you know it is saving you energy?

Click to expand...

I learned how to read the gas meter.

Thanks for the advice, Rugged. By the way, it is a straight, vertical vent. I suspect that I can drill a hole and attach a small tube and run it down the wall to the ground.

As for the 1-800 number, it took me about a month to find a plumber who would even work with one. And I will report back after the honeymoon.

I have heard that old plumbers never die...

Now wait a minute, I thought you was in San Quentin.

Maybe having to look for six months to find a plumber to install it should have told you something. Maybe they know something after all.

halogen25, WAY TO GO !! I use and think the tankless are great !!

Yeah,you should run a condensate line off the vent , just to keep it clear.

Thank you for your post! Lots of these fellows are nasayers and that's fine , but it's O.K. ,,,here in America,,,to have a diffrent opinion .

Cal

6 months , Huh??

if it took 6 months to find someone willing to install

that water heater, I wonder how long it will take to find someone to

service it someday? (when the honey moon is over)

In this thread S. California became South Carolina, and one month became six. That must be why some plumbers hate tankless water heaters.... they have to read the directions!

reading directions

hey, I am grateful that my employees

are able to dress themselves....

its a real bonus when they can read..

Oh, you mean Cabos San Lucas.......ahhh! Now I know where you live. Yeah, definitely a tankless is in order.

codensate line

halogen25,
If there is a connection for a codensate drain then use it . Usually it will void the warranty if you don't use it. The unit you installed.......who makes it and what model is it. I could help you a bit more with that info.

Sorry for such a late response, I just joined this wonderful Forum

outside tankless

Hi GT. Yes, this is a great forum!

I have a Takagi TK-2. Following the advice above, I installed a 45 elbow off of the unit, then a T with a bottom drain for condensate. To this I attached a small hose to drain at the bottom of the unit onto the ground and the vent pipe to the roof. (That stainless vent pipe is certainly expensive!!)

I should note that now 5 months into my tankless, I am as happy as I was the day after installation. (Talk about a long honeymoon! ) It works flawlessly! I highly recommend adding a thermostat controller to have more precise control over the outgoing temperature, especially in a place with very hard water.

By the way, can you recommend any regular maintenance that needs to be done to the unit? I am aware of the info in the manual, such as cleaning the water filter and checking the pressure relief valve. I am a little unsure of how to remove the thermister to check for scale, but I assume it isn't too hard to find with a careful scanning of the component diagram.

here is some info for ya about service

http://www.pmengineer.com/CDA/Archives/8cf9e86f7c298010VgnVCM100000f932a8c0____



read these paragraphs taken from the above article

The cold-water inlet temperature for testing was approximately 58¢ªF. The water was classified as hard with over 15 grains of hardness. The tankless water heaters were °de-limed by circulating vinegar through the coil for one hour between the two-week tests. The efficiency declined somewhat as scale accumulated in the heat exchanger coil. All thermostats were set to provide an average outlet water temperature of 130ªF. The outlet water temperature of the storage water heaters varied more from the average tank setting, but the outlet water did not drop below 120ªF during most of the draws



The operating cost savings for Tankless #2 over a M440T is $603.14 over 12 years, assuming a 4% inflation rate for energy costs. It also assumes that the water system has been softened or that Tankless #2 heat exchanger is periodically de-limed. This savings falls far short of a payback. The venting system material cost makes the economics unfavorable over a storage water heater for residential use. The service costs are an unknown factor for tankless products over this 12-year period. The Tankless #2 heat exchanger has a 10-year warranty, provided the water conditions meet the warranty requirements of fewer than 11 grains for hardness. If any servicing is required, the repair cost is likely to be higher due to the complexity of the controls and higher skill levels required for diagnosing problems.



if you have under 11 parts hardness of the water you should not have to de lime it very often