Jacuzzi/Rinnai Issue.....No Codes

coldlady

Hello,

We have a new house we are building ourselves and installed a Jacuzzi tankless heater that has been in use since Sept of 2013 when we moved in full time. Its myself, my husband and two 5 year olds. Worked great until this past summer (July/August-ish) and started to notice a drop in hot water pressure. We live on a ranch....very remote...but have great water no issues just very hard with calcium/magnesium. We are planning on installing a softener but wow didn't think would need anything this fast. After the noticeable drop this past summer we did the descaling flush procedure with 4 gallons of straight vinegar/pump/etc and things got better but then we started noticing little grayish white specs of "stuff" in the strainers on fixtures, etc.....they seemed to work themselves out until we did not see them anymore but the pressure never did return to "normal" but was still decent. Two weeks ago there was all the sudden a big drop in hot water pressure. We were afraid there were clogs in the line itself (pex line.) Husband opened up some of the line near fittings and we did not find anything at all....all clear. Did not check everything though. Last two days.....like NO pressure to even take a shower or bath with. Awesome since its like 5 degrees outside. Decided to try and do another descale today and started off normally then about 20 minutes into it the exit hose from the hot water port was zero pressure (just a trickle....just like all the faucets) during the vinegar flush. I closed the hot water line off and let the vinegar sit in the unit for a while but have no clue if that will help anything or not.

Any ideas? Have received no codes at all. The pressure is so low now the tank wont turn on to heat the water unless you have more than one faucet on and going and its still a trickle. Tomorrow is New Years so guess we'll put in a service call Friday. Really, really stinks since the unit is only a bit over a year old and all the plumbing & fixtures in the house are brand new. We recently had a guy out from our well service to retest the water in regards to what type of softener/conditioner we'd need and it was re-verified from a couple years ago when we dug the well its still good water just hard.

Eric_32

Did you remove the inline filter in the cold line at the bottom of the heater? Many times we have to remove the screen from the black plastic piece to get good flow when flushing, then clean it and put it back in... be aware of the black Oring in there which seals it from leaking.

You should have a whole house water filter installed also. For sediment, it will extend the heater's life.

We have had a few of the tankless service valves (Webstone) break internally after moving them, sometimes breaking in the open position, sometimes in the closed. It would not happen unless the valve was moved though. If the valve breaks you can't flush the heater properly.

psb75

You have to systematically check every possible, valve, screen, filter for possible obstruction. Hard water sounds like the culprit. You can improve the effectiveness of vinegar by heating it before or during circulation. Your water--"just hard" is a key phrase. Read the fine print in the Rinnai warrantee disclaimer that pertains to "hard water." And there are many different kinds, and degrees of "hardness." Look in the bottom of your tea-kettle for clues as to the nature of your water's hardness, and its effects on heat-exchange surfaces.

icesailor

You really need that softener ASAP. Get a good one and get a big one. Get a 2 cubic foot one. And I recommend that you get one that meters the water and not just backwashes every so many days. You will save a lot on salt. If you go away for a time, it won't be wasting salt on already treated water.

You have no idea how much your life will improve once you get the softener installed. What you will save on detergent/soap will be a very kind thing. And the amount of water you save trying to get the soap out of your hair will be a blessing. Your gray towels will turn white again.

That strainer Eric writes about. Take it out. Soak it for hours in pure white vinegar. Order up some spare screens. They are cheap at twice the cost. The O-Rings too. Do the power flush with the vinegar how ever they tell you to. I would also do this unless someone here tells you to never do this because serious things happen. It never happened to me.

Living out off the dirt roads, you must have an air compressor for nail guns or pumping up the tires on the old ATV. Make something to adapt the hose to the cold water inlet of the heater. When you are flushing, add air to the flowing water so it goes through the heater. Use the air regulator on the compressor to find a balance where you get air and water flowing through the heater. The air will create massive turbulences that will knock off the loose scale and you can then flush it out the hot outlet. If the accessory add on isolation valve kit was installed, you can circulate the solution water through there and with a pump and two 5 gallon buckets, plus the air, you can make the insides look like brand new. Sometimes, you might have to alternate between air and water and back and forth. The heavier viscosity of the water and then air, and back and forth will loosen up obstructions. In my experience.

If you've been running hard water in your system, it is throughout the piping and fittings. Once you install a softener, the "soft" water will slowly remove all the hardness and your water will be the envy of all your neighbors and friends. You can even invite the women over to use your shower and get the old soap curd/residue out of their hair.

That's when you install an outside shower for warm weather use. For many of my customers, life was unbearable if it was warm outside and their outside showers didn't work.

FWIW

Jack

When you remove the filter during flushing be aware that there is a metering turbine in the CW inlet that has to be free or the unit will not work, period. I suggest that you put an old stocking on the outlet when flushing to see what kind of debris you are getting out of the unit. By doing this, you will also not be pumping the debris back into the turbine. Do not backflush.

Error codes are held in memory. Check your manual. If the unit throws a code during operation the code disappears from the screen when flow is stopped, but the last 10 codes are held in memory.

icesailor

I didn't say to back flush. I said to pump out of one bucket, and drain back into another. The crud would be stopped and collected in the second. Filtering the waste would be nice.

I've been to more than one meet and eat session on instantaneous gas water heaters. Not once do I remember a session on how to clean dirty HX'ers. Nor anything in the I/O manuals. Its easy for someone like Tech Support or a rep to tell someone that it can't be fixed and walk away. They don't have to deal with that sick to the stomach feeling when you feel the support fade away and know that some serious blow back is coming when you tell someone that their expensive wall hung toy needs to replaced. When a storage tank type water heater would have been far cheaper to install. And would run for years until the tank failed. Then, you are asked that same exact question by the consumer. As they reach for the phone to "Call Someone Else".

Any fool can install one. Its servicing one, keeping it running and repairing them that takes talent.

Randy-LeeBraman

I agree with Icesailor I have a regular 40hr job besides my small
HVAC biz and that job is maintenance supervisor For a large
children camp and we probably have 60 demand water heaters
tried many brands and we finally settled with Naviens.
and Maintenance is key to keep them running well.All them get a hot vinegar flush each yplace themreear we also pull all the flow valves afterward and give them a good soak and check the the little turbines for frenetic they even look bad we replace them.
one great thing about Navien is they sell a kit that can just about rebuild a unit,i have one for the older models and one for the newer ones,saved my butt a few times and they're great about sending you replacements.But again as Ice said maintenance is the key!!!!!

Randy-LeeBraman

that was once a year flush,sorry.

icesailor

And if you have to drain the whole camp for a seasonal basis, you know that you can drain the entire camp with compressed air from the cold water source? And it doesn't have th be a really high CFM compressor. All the other buildings act as air storage tanks, and you will get more water out of the system with air than you ever will by opening low points. The instantaneous water heaters benefit because the air/oxygen while off for extended periods loosen up the scale inside and it comes out in the Spring when you turn it back on, and you go to flush the heaters.

IME.

coldlady

Wow thanks for all the fast replies!

Eric said:

Did you remove the inline filter in the cold line at the bottom of the heater?

Yes, I took out the inline filter when I did the first flush (water heater used 10 months) and it was clean. I checked it again after the first flush to make sure nothing was in it. Clean. I checked it this flush as well there was a tiny bit of sludgy stuff I was able to wipe with my finger but it was nowhere near clogged. I cleaned it.

psb75 said:

You have to systematically check every possible, valve, screen, filter for possible obstruction. Hard water sounds like the culprit. You can improve the effectiveness of vinegar by heating it before or during circulation. Your water--"just hard" is a key phrase. Read the fine print in the Rinnai warrantee disclaimer that pertains to "hard water." And there are many different kinds, and degrees of "hardness." Look in the bottom of your tea-kettle for clues as to the nature of your water's hardness, and its effects on heat-exchange surfaces.

I knew we had minerals in the water but wasn't too concerned because it tastes great, no staining on house fixtures, really no major issue with water spots wither (certainly not like we had growing up in TX.) I thought we'd be ok for a while! Our most recent test has it at 16 GPG and 160 TDS - the Jacuzzi book indicates that is well below the thresholds for the unit operation or anything that would damage the heat exchanger but that is obviously not our case.

icesailor said:

You really need that softener ASAP.
Living out off the dirt roads, you must have an air compressor for nail guns or pumping up the tires on the old ATV. Make something to adapt the hose to the cold water inlet of the heater. When you are flushing, add air to the flowing water so it goes through the heater. Use the air regulator on the compressor to find a balance where you get air and water flowing through the heater. The air will create massive turbulences that will knock off the loose scale and you can then flush it out the hot outlet. If the accessory add on isolation valve kit was installed, you can circulate the solution water through there and with a pump and two 5 gallon buckets, plus the air, you can make the insides look like brand new. Sometimes, you might have to alternate between air and water and back and forth. The heavier viscosity of the water and then air, and back and forth will loosen up obstructions. In my experience.
FWIW

We do have a compressor...Im going to show this to the husband he is a bit nervous tampering with the unit (and ends up really breaking it) but he might be comfortable doing something like this. He was going to try and take apart some of the fittings to see if its backed up where we can get to it.

After seeing the vinegar trickle out the hot side while trying to
flush it....I feel like its in the heater too. I backed up some vinegar to sit in the unit overnight.....turned the pump on the am and GREAT pressure out of the hose. Then...back to trickle. Am I disturbing something in the water heater thats floating while the vinegar is sitting in there....then as it flows out clogs again? Maybe have him take those flush valves off the heater itself and see if its clogged. Sorry for my lack of accurate terminology.

I will check on the Jacuzzi website about accessing older error codes. I am not seeing any instructions in my book but I will look again. Would like to know how to access those if there were any we missed.

At the moment I wish we would have just bought a regular old tank would have saved a good bit of money but we are off grid were trying to be efficient as possible while having plenty of hot water up in this cold country. We knew the unit needed to be maintained at least once per year. We'll install a softener but need to get the hot water flowing again first.

coldlady

icesailor said:

And if you have to drain the whole camp for a seasonal basis, you know that you can drain the entire camp with compressed air from the cold water source? And it doesn't have th be a really high CFM compressor. All the other buildings act as air storage tanks, and you will get more water out of the system with air than you ever will by opening low points. The instantaneous water heaters benefit because the air/oxygen while off for extended periods loosen up the scale inside and it comes out in the Spring when you turn it back on, and you go to flush the heaters.

IME.

We live here full time...this is not a camp/cabin scenario.

coldlady

And as an offshoot to the issue....the well people are recommending a softener that they sell for about $1800. Its a SoftMAX by Water Tech. Anyone familiar with these? Actually....they have three they said would work for our system the SoftMAX is the middle unit. Sure wish we could get something closer to 1000-1200 but need something that will get the job done and last too.

icesailor

coldlady said:

And as an offshoot to the issue....the well people are recommending a softener that they sell for about $1800. Its a SoftMAX by Water Tech. Anyone familiar with these? Actually....they have three they said would work for our system the SoftMAX is the middle unit. Sure wish we could get something closer to 1000-1200 but need something that will get the job done and last too.

There are lots of softeners out there. All I was saying is that in my experience, bigger softeners do a better job with more reserve, and ones that meter the water run through it are more efficient than ones that just backwash every so many days. When you use ones with meters, say you can handle 2,000 gallons, The meter will "trip" the skipper wheel at say 1,700 gallons so you have good water until the night when it would normally regenerate and backwash. If you hit the "trip" in the early morning, you could go a whole day with dirty water until the unit regenerated. If you go away, and have no usage, you don't waste salt on unnecessary backwashing and regeneration.

And there's all that salty water to get rid of.

Also, IME, you never know what TDS and hardness is going to cause a problem. Until it does. Where I worked, all water was from a sole source aquifer that was shallow to ground level. Little to no hardness, maybe some TDS. But if a driller had to go deeper for better water, they could get into glacial shells and the hardness and TDS would go way up. OK unless you used an indirect heated coil. It never bothered electric water heaters.

SWEI

16 grains is more than enough to cause issues.

Randy-LeeBraman

Ice we do use air but we also pump each unit with non tox antifreeze for insurance.seen air blow by water more then once
specialy the water cooled ice machines.better to be safe then sorry,hate replacing those coils in the Manatoek ice machines.

icesailor

When you blow it until you only get "smoke", there's nothing left of the water. You don't need that big of a compressor, Just the ability to store air. Water heater tanks are perfect air storage tank.

Years ago, I did the "anti-Freeze safe" thingy. After a while, I found that it was a waste of time, energy and anti-freeze.

I never had a broken pipe because I didn't get all the water out. But I saw plenty of broken toilet bowls because one didn't pour a cup of anti-freeze down the toilet tank overflow.

Powerflush and flushometer toilets and urinals drain especially well when blown out with air. You don't have to take the tops off and have someone steal the parts for brass scrap over the winter. Shut off the supply for toilets, drain the tank & Bowl, when done, open the toilet supply, when the water is done running out the ball cock, the vacuum breaker opens, and you have no worry over having split ball cocks.