Surge damper in front of propane water heater?

icarus

Re: Surge damper in front of propane water heater?

If it is a bladder tank, especially if it is a horizontal tank, some water may trap but I wouldn't think that would be a problem. The problem is not freezing per se, but the potential damage caused by freezing. A little dribble of water left in should have plenty of room to expand. I have a vertical tank, and I just open a low point tank drain and have never had a problem.

I agree with Ralph, many of the newer design demand water heaters do not have a water pressure diaphragms. (Rinnai, Takaki, New Palomas etc) As I said, I don't remember what heater you have. The older standing pilot Palomas and older Bosches had diaphragms.

I still think the biggest P-tank you can use the best!

Tony

Cariboocoot

Re: Surge damper in front of propane water heater?

I hate to say "I told you so" but ...

It is most likely the uneven water flow causing the heater to cycle. However, your gas installation was somewhat less than perfect as I recall. Low gas pressure/volume would cause insufficient btu's. Too low will shut it down. Is the heater actually turning off and on, or is the flame just dying down?

And no pressure tank, or any other water system component, likes to be frozen. At least not with water in. Tanks are easily drained from a low point. Remember: gravity is your friend if you work with it.

_OS_

Re: Surge damper in front of propane water heater?

Cariboocoot wrote: »

I hate to say "I told you so" but ...

It is most likely the uneven water flow causing the heater to cycle. However, your gas installation was somewhat less than perfect as I recall. Low gas pressure/volume would cause insufficient btu's. Too low will shut it down. Is the heater actually turning off and on, or is the flame just dying down?

And no pressure tank, or any other water system component, likes to be frozen. At least not with water in. Tanks are easily drained from a low point. Remember: gravity is your friend if you work with it.

Yes, you told me so, Tony told me so and my brother who is running on his third system now told me so But being an (E.E.) engineer I want to experience things myself... One thing is clear; I could never be a plumber! It's easier with batteries and cables; you can always temporary tape something together if you do not have the correct fittings. You can't do that with plumbing. Now I have a big box full of bends, elbows, reduction couplers, equal tees, adapters, you name it. Just in case.

Ole

icarus

Re: Surge damper in front of propane water heater?

There is no such thing as too many items in the "hope chest" at a remote site!

I have one of every thing and two of many after 50+ years to accumulate. The problem is finding them. Nowadays, now that I do get to town occasionally, and there are more options to get some specific hardware it is pretty easy to go get the "right" fitting rather than searching through the "hope chest".

Good luck,

Tony

westbranch

Re: Surge damper in front of propane water heater?

Hi Ole, a few words about instantaneous water heaters.

We recently installed one ( variable from 19,000 to 195,000 BTUs) in our home and are having hot/cool problems with the shower for the first 2 - 3 minutes then it evens out. I have spoken to the Manuf. tech people and they blame a small piece of ?? crud?? or ?? on the flow sensor, but we found nothing...

We have a 100 m deep well, static level about 75 m , with a 3/4 horse pump, into a ~60 L bladder type pressure tank set at 35 psi on, 60 psi off, and we still have some issues...

My thoughts are:

get the largest P-tank you can fit in , mount it as high as possible, and as far away from the heater as possible.

Use PEX type ($$$) pipe as neither it nor the joints will split if there is still some water remaining over winter,

the hardest thing will be getting all the piping going downhill so that it naturally wants to drain.

Install bleeder (air) valves at the highest points to enhance draining.

Cheers
Eric

icarus

Re: Surge damper in front of propane water heater?

Eric,

What brand is your water heater? I have had similar problems with Bosches lately,

Tony

westbranch

Re: Surge damper in front of propane water heater?

Tony it is a Navien, new on the market in our town. http://www.navienamerica.com/product/boxes_01.aspx?skin=boxes_01 Made in Korea.

FWIW the winter gas use was about the same as our old High Effic Lennox, now discontinued for good reason...

but the summer use has been about as low as they will measure, our $ bill is about a third of last year for the same period, and rates are about the same.

Eric

icarus

Re: Surge damper in front of propane water heater?

Looks pretty cool. What is it's AC draw? Ball park cost? I didn't down load the whole PDF, Propane and Natural?

Tony

_OS_

Re: Surge damper in front of propane water heater?

Hi Eric,

Thanks for the suggestions.

I never heard of a Heating Box before and I am not sure I understand what it is. Is it a device that let hot water from another source to the inlet of a gas heater to reduce gas usage?

Ole

BB.

Re: Surge damper in front of propane water heater?

The "Heating Box" appears to be a heat exchanger. Take hot water from a single tanked or tankless water heater and direct hot water to faucets plus, at the same time, heat through a heat exchanger to a closed loop hydronic heating system with antifreeze/anti-corrosion chemicals (hot water radiators and/or in floor heating pipes).

-Bill

icarus

Re: Surge damper in front of propane water heater?

In off site conversation with Erc (WestBranch) I think he has the demand water heater build and sold by the same company rather than the "heat box". If you follow the link to "products" you will see the demand. It looks pretty interesting in that it can be vented through a PVC pipe rather than the stainless required for many of the Hi-Ef demand units that I have used.

Tony

PS I may be wrong too!

westbranch

Re: Surge damper in front of propane water heater?

Gentlemen, to be succinct:
I have both the instantaneous heater and the 'heat box'.
The Inst. heater heats domestic water, which in turn goes through a pair of heat exchangers in the "Box"and then to the furnace.

The combined unit thus provides us with DHW and house heat. Hot air heat is through a 'radiator' in the hot air plenum of our furnace.
I believe the "Box" was originally designed for 'in floor heating' ie in a concrete slab.
Our house is ~1300 sq. feet with a full basement.
In - 35 C the unit can heat the entire house easily. We did not get colder than that last winter.

The original furnace was/is a combo wood/oil furnace that is now a redundant (duplicate) heating unit.

I kept it just in case we needed heat when the grid power failed, which it did frequently in the 'old' days. However, our previous hi efficiency Lennox boiler failed last year:grr 1 week before Christmas and that redundant unit was revived so that we were able to have house heat and a modicum of hot water while the oil heat was running.

Apart from a few idiosyncrasies I really like this new Navien unit, much quieter than the Lennox and more cost efficient in the summer for sure due to its 'demand' heating function for DHW. House heat has not been on for 3 months now.

the unit installed was ~ $C 10,000
HTH
Eric

_OS_

Re: Surge damper in front of propane water heater?

Last weekend I mounted the two liters P-tank that I got from my brother after he upgraded his cabin system. The pressure in my system is more even now and we can wash our hands without the pump starting. Below is a picture of the pump with tank attached as well as a picture of the tank.

I will test the system until next spring and then decide if i need a bigger P-tank and bigger gas heater.

Ole

PS: Sorry about the mess in the corner behind the pump!