Question about Bosch Water Heaters

Open Question

Aquastar (Bosch) 125X LP intermittent problem. Won't always light up.

New batteries, rebuilt valve assembly, new microswitch assembly, new diaphragm...all to no avail. Microswitch does not click when it doesn't work. Playing with adjustment at those times doesn't help. I'm thinking it may be a bad control unit or bad ground to control unit. What else could it be?

Posted by Anonymous on

Ad

6 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya Repairman can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Repairman (only for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad
snap101
  • 117 Answers

SOURCE: Whistling Bosch AquaStar 2400ES-NG

if you have incorrect gas line size when it kicks on the lack of gas pressure to the unit will cause a wistling. make sure you have enough gas to the unit

Posted on Jul 29, 2009

Ad
mrhotandcold
  • 248 Answers

SOURCE: On-demand Bosch Confort 13 water only works intermittently

will still be under warrent call supplier

Posted on Oct 25, 2009

  • 832 Answers

SOURCE: Had the unit for seven years, it started to leak

You have to fix this leak around the water valve before
it causes damage to your equipment.
1. Close the water supply valve going to your tankless
water heater.
2. Unplug or close the natural gas valve.
3. Now, you can work fixing the leak.
4. Once completed, you can proceed to open the
natural gas valve as well as the water supply valve.
5. Then, have it tested to get it done.

5.

Posted on Nov 28, 2009

  • 33 Answers

SOURCE: Bosch Aquastar 2400E LP Does Not Heat Water

Sounds like the water flow sensor and servo, may just need cleaning, get it checked out by a Bosch agent

Posted on Jan 17, 2010

  • 133 Answers

SOURCE: 5yr. old aquastar 125x lp

The gas valve makes a single click sound when the pilostat shuts off. That is a safety holding coil for units with standing pilot lights and closes if it thinks the pilot went out. In electronic ignition, the same holds true except the sensor is electronic.

Posted on Mar 31, 2011

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Pilot does not ignite?


Look for the pattern of flashing lights when it fails after you turn the power off/on. Then look at the wiring diagram / instructions on the inside of the panel. The flah pattern should be listed. For example, two green flashes and pause, repeating may mean that the exhaust flow is not sufficient, or another flash pattern may indicate pilot is not lighting.

Likely ly a pressure switch is bad or exhaust is blocked.

May 17, 2015 | Water Water Heaters

1 Answer

No clicking sound


When you do not hear clicking the first thing to check is to the check the microswitch. See my answer on this question: http://www.fixya.com/support/t9769963-bosch_model

Apr 22, 2014 | Bosch 1600H-NG Natural Gas AquaStar...

1 Answer

I have a Bosch 125x NG tankless with no power light. I have replaced the batteries. This happen just after the hot water supply line burst and spewed water up into the heater. Im thinking this was caused...


Sounds like the watervalve was never serviced. It will stick if its not serviced every 3-5 years according to the manual. If it sticks, it can keep your burners on after waterflow, and overheat the water still in the exchanger. This can cause plastic/pvc/pex to swell and burst. Thats why any machine says to have only metal lines connected for min of 3 feet.
Since it got wet, you may have to replace your control box as well, but at least maintain your watervalve and recalibrate your microswitch. Those last 2 may be your only issues.

Nov 02, 2013 | Bosch & Tankless LP Hot Water Heater

2 Answers

I recently had my primary heat exchanger chemically cleaned. My thermostat changed ad it had been re pressurised. The radiators all are working fine, but my water is still going hot and cold. What could it...


Could be the HW sensor, When you ask for HW, a switch ion the boiler will operate, usually part of what is know as 3 way valve. Different types of switch, you will have to have a look, could be a microswitch, in a unit to the side, you will be able to see if operating. But more likelly to be the 3 way valve itself, The internals do not switch fully, internal leaks etc. So inconsistent HW. Very easy to replace yourself, Turn off cold water, and isolate all the CH side, drain down the boiler, replace unit, reopen all valves, check pressure, off you go. You can get service kits for the 3 way valve unit, But for price diference, just replace, ebay a good place to to get one from

Mar 04, 2013 | Water Heaters

2 Answers

I can no longer hear the clicking on the ignition therefore there is no longer a flame to heat the water. Everything else seems to be working fine.


If there is not a clicking sound, it almost always means the main ignition or control unit (box with red and green lights and wires coming from it) is not getting the supply voltage. The voltage is supplied by a generator that is getting energy from the flow of water (the "hydro generator"). First disconnect the wire connector at the hydogenerator and check the voltage while water is running. The manual says you should read 1.6 VAC (I read 2.5 VAC). Make sure your voltage reader is on AC, not DC. If you have at least something like 1 VAC, then the next thing to check is the "microswitch" that allows the hydro generator voltage to reach the ignition unit. To check it, disconnect the other wire connector that is on the black wire coming from the hydrogenerator that is closer to the ignition unit. Then with the water running, stick a small screwdriver in the male plug side to short the two wires in order to bypass the microswitch (per Bosch tech support instructions). You should now here clicking and see the unit work. This is what happened with me and tech support said I needed to order a new microswitch and gave me a part number and telephone. But don't stop reading here. You can see the microswitch when looking up at the underneath of the unit. It's a small white 1x1 inch box-like shape held by 1 screw. After removing it, I noticed the microswitch had a removable cover (which is strange for a switch) and opened it to discover the internal switch can actually move inside because it "automatically adjusts" itself when it is first put in (it stays more firmly, but not rigidly in place when the cover is on). So you can mess up when putting it in. Don't bump it. It can easily get out of its working range of motion, which is why mine stopped working: it was a bad design to use this type switch in this application. So I slide the internal switch back close to the spring side ("default" position), put the cover back on, carefulyl screwed it in place, and now it works.

The purpose of the mechanical microswitch is to not allow the hydroenerator voltage to the ignition unit unless the "pushrod" has opened the main gas supply. It prevents clicking if there is no supply gas, so it is not needed (you can electrically bypass it with a splice) if everything else is working fine. But don't blame me if you do this and for some reason it ruins the more expensive ignition unit. The microswitch is turned on by the pushrod when the pushrod leaves it's default position. The the pushrod moves only about 2 to 3 mm when you turn on the water. You can see the pushrod when you unscrew the microswitch, and you can watch it move. The problem is that the microswitch mounting is not precise enough for the small pushrod movement and the pushrod's default position can change with age of the diaphragm or change in the grease. So their automatically adjusting microswitch that makes up for lack of precision in design and pushrod movement can stop working when the pushrod changes position. My unit was 2 years old.

Sep 05, 2011 | Bosch 1600H NG AquaStar 4.3 GPM Indoor...

2 Answers

I have a Bosch Model GWH 1600 H tankless water heater. I have had issues with it since I installed it 2 years ago or should say had it installed.Yesterday I could not get it to ignite or light manually. I...


Igniter can be ordered, but that may or may not be the issue.
Your tankless unit -and- plumbing system need total check-up by trained service technician.
Open following links for Bosch troubleshooting resources including contact Bosch, manuals, error codes, water flow etc.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
http://waterheatertimer.org/pdf/No-Error-Code.pdf
Check electrical outlet with circuit analyzer to make sure polarity is correct.
Typically, gas water heaters, and especially tankless water heaters require yearly maintenance by service technician who can check the gas pressure and supply, venting, electrical connections, PC board, sensors, burner orifices and igniter parts are clean and positioned correctly, vent is draining correctly and not dripping back into combustion chamber, correct temperature is achievable, incoming water temperature is not too cold for temp setting, proper incoming air supply, adequate air supply, no chemicals stored in air supply pathway, filters are clean, plumbing check valves, mixing valves, pressure valves etc are permitting one-way flow of hot water, water is softened to less than 11 grains hardness, water is filtered and not dirty, aerators and other faucet parts are clean and support water flow necessary to activate burner.

Jul 15, 2011 | Bosch 1600H-NG Natural Gas AquaStar...

2 Answers

Aquastar gwh 1600 h igniter fails clicks does not spark


If there is not a clicking sound, it almost always means the main ignition or control unit (box with red and green lights and wires coming from it) is not getting the supply voltage. The voltage is supplied by a generator that is getting energy from the flow of water (the "hydro generator"). First disconnect the wire connector at the hydogenerator and check the voltage while water is running. The manual says you should read 1.6 VAC (I read 2.5 VAC). Make sure your voltage reader is on AC, not DC. If you have at least something like 1 VAC, then the next thing to check is the "microswitch" that allows the hydro generator voltage to reach the ignition unit. To check it, disconnect the other wire connector that is on the black wire coming from the hydrogenerator that is closer to the ignition unit. Then with the water running, stick a small screwdriver in the male plug side to short the two wires in order to bypass the microswitch (per Bosch tech support instructions). You should now here clicking and see the unit work. This is what happened with me and tech support said I needed to order a new microswitch and gave me a part number and telephone. But don't stop reading here. You can see the microswitch when looking up at the underneath of the unit. It's a small white 1x1 inch box-like shape held by 1 screw. After removing it, I noticed the microswitch had a removable cover (which is strange for a switch) and opened it to discover the internal switch can actually move inside because it "automatically adjusts" itself when it is first put in (it stays more firmly, but not rigidly in place when the cover is on). So you can mess up when putting it in. Don't bump it. It can easily get out of its working range of motion, which is why mine stopped working: it was a bad design to use this type switch in this application. So I slide the internal switch back close to the spring side ("default" position), put the cover back on, carefulyl screwed it in place, and now it works.

The purpose of the mechanical microswitch is to not allow the hydroenerator voltage to the ignition unit unless the "pushrod" has opened the main gas supply. It prevents clicking if there is no supply gas, so it is not needed (you can electrically bypass it with a splice) if everything else is working fine. But don't blame me if you do this and for some reason it ruins the more expensive ignition unit. The microswitch is turned on by the pushrod when the pushrod leaves it's default position. The the pushrod moves only about 2 to 3 mm when you turn on the water. You can see the pushrod when you unscrew the microswitch, and you can watch it move. The problem is that the microswitch mounting is not precise enough for the small pushrod movement and the pushrod's default position can change with age of the diaphragm or change in the grease. So their automatically adjusting microswitch that makes up for lack of precision in design and pushrod movement can stop working when the pushrod changes position. My unit was 2 years old.

Mar 04, 2011 | Bosch 1600H-NG Natural Gas AquaStar...

1 Answer

Vaillant ecoMAX 828/2boiler goes on & off when running hot water!


water must be set at 3lts a min ,check diaphragm valve move when hot tap is on, check microswitch ,best of luck

Aug 09, 2009 | Water Heaters

8 Answers

Bosch tankless GWH 1600 H NG won't always ignite. The igniter sparks, but doesn't always light the gas. It just clicks. When installed it lit every time, now it takes more and more tries to get it to...


The clicking is a good sign. What are you trying that not working? How is the water flow-is it strong? 1) Turn the flow control button all the way to your left - this will increase the flow.
2) Pull the relief valve to simulate water flow and listen for clicking sound, and hopefully, main burner ignition. ( if installed in basement or kindly use bucket to catch water) The 1600 H NG will automatically shut off firing after 5sec of clicking.
3) How is the venting-use a household digital carbon monoxoide detector to measure any backspill from chimney.
4) Was the gas line disconnected in anyway after heater was installed? Air in the gas line will cause the igniter to click but no gas to fired the main burner.

Todate i have installed 11 Bosch Tankless Heaters -- 9(125 NG) Which is the same as 1600 Series
1(1600H NG) and 1(1600P NG)
Guess which one I having problem with- You guess it, however, the problem is their electrical wiring.

BE CAREFUL IN CALLNG BOSCH TECH. FOR SUPPORT. THE ARE GRILLING YOU TO FIND A LOOPHOLE WITH YOUR INSTALLATION TO RELIEF THEMSELF OF THEIR WARRANTY.

Jan 25, 2009 | Bosch 1600H-NG Natural Gas AquaStar...

Not finding what you are looking for?
Water Heaters Logo

Related Topics:

33 people viewed this question

Ask a Question

Usually answered in minutes!

Top Bosch Water Heaters Experts

Colin Stickland
Colin Stickland

Level 3 Expert

22265 Answers

Donni Steen

Level 3 Expert

659 Answers

john h

Level 3 Expert

12744 Answers

Are you a Bosch Water Heater Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...