installation of Rinnai by homeowner
KWOLSEN
| Posted in Energy, Heating & Insulation on
I’m considering installing a Rinnai tankless water heater, external mount in one of their recess boxes. My local industrial supply will gladly order one for me, the question is with all the discussion about Rinnai’s only to be installed by factory-trained people—- if I, the homeowner install it with no training, can I get warranty work done in the future without having a receipt from some trained installer ? (Anyone from Rinnai Corp. care to explain why they have this silly rule ?)
thanks,
Kirk
Replies
I installed my own instant hot water heater about 2 months ago. This was to replace an older (18 years) Bosch. The new unit is a Ferolli (Italian) My system, like the Rinnai you are looking at is also a sealed system. Mine is a bit more complicated since it also heats my radiators, so it has two water loops. This gives a total of 4 standard sized water fittings, 1 gas line, and 1 exhaust/intake, and the electric line.
Assuming you know how to properly and safely hook up the gas line (per code) there is nothing complicated regarding the install. The unit itself comes after testing at the factory. What would require specilized training is any changes such as type of gas (LPG/NG) Also some locations require that the exhaust be checked for proper CO ratio which unless you are an HVAC tech you would not have the equipment for.
My guess it that the real reason for the install requirement is CYA, or avoid the lawyers.
One thing that you should be aware of is that if you turn the water on and off during usage, the temperature of the water will varry. When you stop the water, any water in the heat exchanger becomes very hot. When you turn the water back on, the gas will not come on immediately so you will first get a blast of very hot water followed by rather cold water. Since the same thing happed with the older Bosch (and a mini electric unit I have), the only conclusion is that this is an inherent design issue with any instant hot water heater.
Yisrael
One thing that you should be aware of is that if you turn the water on and off during usage, the temperature of the water will varry. When you stop the water, any water in the heat exchanger becomes very hot. When you turn the water back on, the gas will not come on immediately so you will first get a blast of very hot water followed by rather cold water.
I am not completely sure of what you mean by turning the water on and off during usage, but if you simply mean opening and closing faucet valves, then no you shouldn't get a blast of very hot water when you first turn on the water again. You should get a stream of warm to cold water until the heat exchanger gets going. My Rinnai unit nevers gives me such a blast of hot water, just the cold until newly heated water arrives. It may vary from manufacturer to manufacturer, but I would be concerned about a design that did that.
but if you simply mean opening and closing faucet valves, then no you shouldn't get a blast of very hot water when you first turn on the water again. You should get a stream of warm to cold water until the heat exchanger gets going. Once the water heater is up to full temp, turn the water off for several minutes, and then turn the water back on. You will get significantly hotter water than normal. The water which sat in the heat exchanger simply warmed up more. When the water is turned back on, the thermostat will sense the high temp water and keeps the burner off until it cools off a bit. At this point, some cold water will come through. Mostly we notice this when giving the kids a bath, at which point it is annoying. Turn the water on, rinse, turn water off, shampoo, turn water back on, wait for the temp to stabilize..... From what I have heard, this is a fairly common complaint (and just about the only complaint) regarding instant water heaters.
Once again, I have seen this with at least 3 different types of instant water heaters, 2 gas, 1 electric, all of them from good, respected companies.From an engineering point of veiw (I happen to be a mechanical engineer ) This result is to be expected based on 1. the rules of heat transfer, and 2. the feed back control systems. The elegant way to eliminate this problem would be to add a mixing valve after the heat exchanger. This would also probably price the heater out of the market. I agree that opening and closing the faucet with fairly short intervals does not cause a significant change in temp.
Older units were also problematic at low flow rates. They would heat up a bit to much and cut out. Newer units (anything for sale now) have significantly better controls and gas valves. As long as the water continues flowing at the minimum flow, the temp remains stable.
Once the water heater is up to full temp, turn the water off for several minutes, and then turn the water back on. You will get significantly hotter water than normal. The water which sat in the heat exchanger simply warmed up more. When the water is turned back on, the thermostat will sense the high temp water and keeps the burner off until it cools off a bit. At this point, some cold water will come through. Mostly we notice this when giving the kids a bath, at which point it is annoying. Turn the water on, rinse, turn water off, shampoo, turn water back on, wait for the temp to stabilize.....
You may have this problem with your tankless unit, but I don't have it with mine. Perhaps the water temp rise is so minimal as to be unobtrusive, or the hot water mixes with the cold water that initially runs through the heater once the flow resumes. My point is that while this may be common with some heaters, it is not a quality which all tankless heaters share by necessity of design.
I am glad you don't have this problem, I wonder if the difference might be in the fact that mine (and the older one I replaced) both heat the radiators in addition to hot water. The heat exchanger is double sized as a result (one loop for the radiators, and a seperate loop for domestic hot water) since the exchanger is significantly heavier than a unit for just hot water, this may well be the difference.
I think that you already know why they say this. They don't want to be responsible for any problems that you may have caused through the installation. Every company is different with how strict they are with their warranty. Some may mention all kinds of ways to get out of paying for warranty work. Then when something seems to be a reasonable claim they will take care of it, even if they could get out of it through the fine print. Other companies may not cover anything and try to get out of covering anything, and the warranty is garbage. If the product is very good and unlikely to fail you'll never get to find out how valid the warranty is. I don't know anything about Rinnai's customer service or product reliability long term. There are several Rinnai direct vent room heaters here where I work, and after 2 years they have had no problems. Some of the work that the licenced installers did was way below my own standards, and it hasn't seemed to matter yet.
If you know what you are doing and can do the job right you could do it. It's a gamble. If you need warranty work done and they don't cover it, the cost could be more, less, or equal to what you saved by not paying someone to install it. I always take this gamble, and in the long run have come out way ahead.
I have two Rinnai units- a tankless water heater and a direct vent wall furnace. I installed the wall furnace myself, and was assured by my vendor that it would not void my warranty. The tankless water heater regs seem more strict, so I had my plumber do that one. To be honest with you, I think the wall furnace was more complicated to install, but I wanted to preserve my warranty options. If the unit arrives dead or injured, and I had voided the warranty by installing it myself, I didn't want to eat the $1100 purchase price. It is kind of like buying stocks- you have to match your desires for return (or savings, in this case) with your tolerance for risk/loss.
Mike-thanks for the reply. Can you explain what about the water heater requirements that were more strict, don't want to overlook something here.
thanks,
Kirk
The requirements had more to do with Rinnai's willingness to sell wall furnaces through third parties, who then back up warranty claims even if there is no approved installer. The water heaters were much harder to purchase if you weren't a licensed plumber, and Rinnai seemed more insistent that an installer do the work. At least that was my experience in my area. Officially, they may be hesitant to warranty any installation, be it for a wall furnace or a water heater. They suppliers simply seemed more flexible.
How do you like your direct vent Rinnai wall furnace.
I put one in a couple years back after going out of my way chasing one down but really like the thing as it just sits there and works without having to pamper it.
Installation wasn't too awful complex for a DIY except I'd about hit the limit on the wall thickness without needing to get an extension package for the vent pipe.
I'd do it all over again.
be satisfied
'Nemo me impune lacesset'No one will provoke me with impunity
I love the Rinnai furnace. My house has an open floor plan and is well insulated, and the Rinnai serves as the perfect complement to my woodstove. It was a fraction of the cost of a central heating system and does all we need. I was able to locate it in a hallway nook and want to build a built in cabinet with flipper-type retractable doors to hide it in the summer time. I needed an extension kit because it vents through the back of another closet, but it seems to work perfectly. The vent tube gets warm to the touch, but not warm enough to burn your hand.
They can be hard to find, but I think they are light years ahead of the domestic competition, i.e., the Empire type units, in terms of function and durability. The aesthetic police (wife) vetoed those based purely on appearance.
A similar product to the Rinnai, with a proven track record IMO, is a Takagi on-demand water heater, and Takagi allows the DIYer to install their units. Just something to consider.