13 of 13 people found the following review helpful
Good water heater; thoroughly vetted,
Verified Purchase(What's this?)
This review is from: Bosch 1000P LP AquaStar 2-3/5 GPM Indoor Tankless Gas Water Heater (Tools & Home Improvement)
I wanted to wait until my heater was completely vetted and it proves wise as it had a problem after about 2 months that may come to help other customers. So the negs:
After 2 months use the heater all of sudden literally went from flame on working to stopped cold, pilot out. The only clue I had was that the pilot would come back on - only while I had the gas button depressed on - but the flame was very yellow indicating a gas rich flame (too much gas/air mixture). The solution was in the manual which you can download from the product page above the item #. So the remedy in my case was to clean the throttle tube which is best done with automotive carb or injection cleaner. This is part of a regular maintenance cycle anyway but it happened soon on mine. Even a small amount of gas soot in the tube was causing an over-rich mixture of gas.
There are only a few other minor issues with this heater such as the discrepancies between the manual and the heater: the cold water inlet is 3/4" and located facing the back of the heater toward the wall and the manual lists it as a 1/2". This really makes getting a copper heater hose on there a trick but I wouldn't recommend using anything smaller in diameter hose than that as your water flow is limited by that size input. Similarly the hot output which is the copper pipe hanging down exposed will limit your output quite a lot and I recommend increasing the size after the supplied 1/2" hose to 3/4 at least.
A very confusing marking on the heater is the temp control knob indicator: turning it CLOCKWISE increases the temperature by also reducing the amount of water it takes to activate the flame (activation rate). Turning it COUNTER-CLOCKWISE reduces the temp and increases the amount of water it takes to activate the flame. The indicator marker is reverse to normal hot water heaters: there is a widening strip of black above the knob but it widens toward the counter-clockwise direction whereas normally the widening of that strip marks hotter this one marks cooler (zoom the pic and you'll see). The manual is not very clear about this knob and it's key to understand the activation rate.
The last discrepancy is in the size of gas pipe you would use, the manual tells you not to use a smaller diameter than 1/2 but that is nearly impossible if you use the correct size regulator on your tank (74,900 BTU see my install tips below).
One last small gripe is purging this heater of air in the gas line is a very tedious process.
Now the positives:
I have run the heater with only a sink on the lower of the 2 flame settings with the temp control nearly all the way up. This gets the water hotter than I can touch it. And it will run for over a month on 5 gal. of propane with daily use. The heater itself is fairly easy to put together all in all once you have the vent installed the rest is basic plumbing.
Starting with the external regulator at the tank as others have mentioned you will want 1 that gives you exactly 74,900 BTU (this is common for hi-temp grills and the like Mr. heater products). My Mr. heater regulator output is 3/8" pipe thread which is the nominal gauge for this class of gas flow still considered low use. So 1 way or the other you're going to want to increase the size back to 1/2 which is how the heater connects. I used a 3/4" stainless flex tube to go between the inside and outside. Then reduced back down to 1/2 using a tee to make a drip leg with a 6" pipe nipple that drops straight down below the heater while the fuel line comes in horizontal. The one thing that can't be stressed enough is to keep your water lines as large as possible. Mine are 1" down to a 3/4 flex copper hose on the inlet and 3/4 rigid copper on the output past the 1/2" initial. Once you have the heater connected the only trick is to bleed the air out of the lines. The manual doesn't really tell you much about this process except that eventually when you hold down the gas and strike the lighter after a few min. it will light. Well there is an easier way but unless you have adequate venting you don't want to attempt it. My heater is in front of a window so I can open it and crack the flare fitting of my flex line. You really only let air out anyway and the minute you smell consistent gas (strong garlic an onion as Lp has no odor so it's scented) you shut it down. This puts out no more gas than an oven lighting up and is a much quicker route to getting air free. It still may take a few tries at lighting by striking every few seconds and holding the gas down but it's better than doing that for several minutes.
All in all this is a good heater for a sink and a shower, if I were to add a shower I would definitely continue the raised copper lines which run through my ceiling and a shut off valve so that the water would not sit cold in the lines. A great trick with this heater is when you open a water valve it lights up and heats the water that flows through it. So by opening a valve to the shower you would have nearly instant hot water. I also make use of a very small 25W electric water heater that sits right in front of the Bosch and this keeps water hot straight up to the tap.