Bosch Hydropower 10H Instanteous Gas Hot Water Heater

Home & Living
1

A friend recently had a Bosch Hydropower 10H Instantaneous Gas Hot Water Heater installed (and had a new gas line installed, too). And it quit working right away.

Curious if anyone else has had problems with this unit – see issues below.

She called the plumber who came out & told her that the gas flame was yellow & that a spider had blocked something and that she had to use insecticide to keep the spiders out of the unit….

(And I think she was charged for the plumber visit – even tho’ the unit was brand new…)

She has had instantaneous hot water system for 30 years that finally gave out & she replaced it with this unit. And she had no problems with spiders or the unit not working.

I have had & currently have an instantaneous hot water system for many years & never had a problem with spiders.

I did read on whirlpool (post from 10 years ago) someone said that their plumber had said the same thing about yellow flame being caused by spiders….

And note, for the sake of our environment, I’m opposed to implying that spiders are the cause of hot water heater faults and plumbers suggesting that insecticides should be regularly used. If not a problem for the last 30 years why now???

Is it really a design issue with the heaters & spiders are an excuse???

I have another friend who worked for the gas company & he said that the yellow flame is caused by lack of air in the air/gas mixture (and that it can create carbon monoxide problems if not corrected – but as most gas hot water heaters are installed outside (as is my friends & mine) so likely not a problem).

I just read the product blurb on the Bosch website (seems like a good idea – as will have hot water, if there is an electrical outage….) – Bosch Hydropower Hot Water Systems | Bosch Thermotechnology

I said I’d ask the Choice Community (as I am a Choice member). I also looked on Choice.com.au but didn’t see any reviews or information on various instantaneous gas hot water heaters to see how brands compare…. Maybe these have fallen out of fashion (move to electricity, solar power)?

3 Likes
2

Yes, Choice has made a decision.

Re the Bosch gas instantaneous hot water heater.
We have a different model which requires a mains power point. That it will not operate without electrical power we consider a minor inconvenience. We also rely on rain water and an electric powered pressure pump for our water. No power, no water, so no need for the HWS when the power goes out. The Bosch has been reliable for more than 10 years.

Typically a Plumber with Gas Fitting License will be able to install units such as the one purchased. It’s less likely they will have the knowledge or resources to identify and remedy a fault with the Bosch unit. The plumber/gas fitter installer should have ensured there unit was correctly installed, connected. Also that the water and gas supply was as specified by Bosch.

Bosch can provide support, contact details per Bosch Hot Water & Heating - Residential | Bosch Thermotechnology

To also note that the supplier of the Bosch HWS, IE the business you paid for the system is firstly responsible for providing a remedy as required by Australian Consumer Law. A longer discussion, although the main Choice web site provides advice, if any are uncertain. What every Australian consumer should know about their rights

To assist any others who may be able to post a reply, it would be beneficial to indicate how or who from the Bosch HWS was purchased. Also how and with whom the install was arranged and who completed the install/testing.

4 Likes
3

Ok – first I respect the Choice decision not to review gas appliances. (Just noting new offshore gas wells being considered/drilled/approved by the Vic Gov’t off the Vic shores near the 12 Apostles….).

Will gather & share some more info on the gas hot water heater purchase & installation – and thanks for the links – very helpful.

Thank you.

3 Likes
4

A yellow flame is indeed caused by insufficient air at the burner but whether it was a spider or from the installation will never be known excepting for trust in whomever made the observation.

Did you mean the HWS never worked, or worked for a brief time (minutes or hours) before it stopped working?

Spiders can be one off events. My spa tub whirlpool motor stopped moving water after a decade. A spider covered a venting hole with its web. Once cleared it has not happened again over another decade.

If the unit was working properly when installed I doubt Bosch or the installer will take ownership of a spider event. Assuming it was a spider as reported its nest could have been interfered with during installation of the unit and new gas line. Once resolved not likely to repeat as the spider made a new nest?

3 Likes
5

A spider or anything covering the air intake hole will reduce oxygen whilst gas will still flow. This, of course will cause a yellow flame. It would need to be unblocked and would be OK. Spider could have come from wherever the unit was manufactured. Not the manufacturers nor plumbers fault,

2 Likes
6

In addition to spiders…it could also be something from the gas line. Dirt, dust, piece of corroded pipe etc which has travelled down the plumbing to the gas injector, and is caught on the injector. This could restrict flow causing yellow flames.

As it is a new heater and the problems started almost immediately after it was installed, it could be that some contamination from downstream of the heater in the gas lines caused the issue. The contaminant could have been dislodged/disturbed as a result of the new heater installation.

Like above, if this is the cause, it isn’t a manufacturing fault or an issue caused by the plumber.

If the plumber caused the contamination (e.g. as a result of not adequately cleaning out the connections before installing), then the plumber may be responsible. However, knowing the source of contamination will be next to impossible to determine.

1 Like
7

Thank you everyone for your input. Here is an update.

Evidently the hot water heater could be up to 12 months old…. (not very recent install).

Bosch did send out an authorised person on Monday & he is the one who said that it’s a spider – she saw the spider & said it was about 1/4 the size of a pea & the person also cleaned out the soot. He also said the problem was on her end & charged her $340 (not covered under warranty).

This morning (Thursday) the hot water heater did not work again! An unpleasant surprise on a winter’s day when you’ve undressed in a cold old weatherboard & ready to get into the warm shower!

So Bosch has been contacted again & I guess will come back soon. Of course, she still has no hot water.

So what is going on?? Don’t think the spider can be blamed this time….

My friend said she would let me know the outcome.

It seems to me that she should not have to pay for another visit from the Bosch representative if the ‘fix’ only lasted 3 days?

The plumber she used for install (who furnished the unit) evidently is also an authorised Bosch person.

She has help from her neighbours in organising – as she is elderly & not up to lots of research, internet searches etc etc.

She is looking for her paperwork and talking with the neighbours who helped her to try to figure out date of purchase etc. She is trying to determine her rights under warranty.

Like many things, it gets confusing. I would say that she has done everything requested on her end (new gas pipes) and has not done anything detrimental to the unit.

She just expected that she would have many years of hassle-free hot water.

She is going to let me know what happens when Bosch licensed person comes out again.

Thanks again for everyone’s input.

3 Likes
8

It might be worth checking if a gas pre-filter (liquid phase filter or inline vapour filter) has been installed immediately downstream of the water heater. These are used to ‘scrub’ the gas by removing debris and other contamination which may travel along gas lines.

I assume the water heater is connected to reticulated supply. Even if the pipes from the meter to the heater are new, contamination can occur from downstream of the meter. Contamination can also occur from new lines as well (residues from manufacturing, loose soldering materials from capillary fittings etc).

Likewise, if it is bottled gas and new lines are installed to the gas bottle. A gas bottle could also be source of contamination.

If a pre-filter isn’t installed and the injector has evidence of a blockage, it might be worth exploring.

It is likely additional payment will be required, especially if the problem isn’t stemming from the water heater or how it is installed. I would be asking whoever comes out to look to see if it is contaminants in the gas line causing the problem and whether it is worth installing a pre-filter, if one isn’t already installed.

If a pre-filter has been installed, this might point the problem towards faulty injector or ‘spiders’.

1 Like
9

No idea what this means – but she lives in inner Melbourne so I assume the water is ok?? (It’s not ‘grey’ or recycled water…..)

Not bottled gas – she was told to install new gas lines & she did (at some expense) – as hot water is important (for us all).

I thought the yellow flame & soot indicated a problem with the ‘air’ not with the gas line?

I assume since the install was by Bosch approved plumber that they put in whatever was required… “ gas pre-filter (liquid phase filter or inline vapour filter)”. Am sure she has no idea about this…. I guess I can suggest she ask the plumber about it – as he will be at her place soon – we hope…

BTW, the website on the marketing tag put by the plumber on the hot water heater links to a website that doesn’t exist (and couldn’t exist as the URL doesn’t use the proper syntax)…. Again we assume if Bosch certified that the plumber knows what he is doing…. (even if not Internet savvy).

Makes me appreciate my own instantaneous hot water heater more than ever – it works!

1 Like
10

Reticulated supply means the water heater is connected to piped network that delivers gas (natural gas or LPG) directly to a home from a centralised source. It is standard terminology. Often it is called ‘town gas’ as it is easier to say.

Yellow flame means the air to gas ratio isn’t at an optimum ratio. It occurs when either air or gas is impeded in some way… or there is to much of one compared to the other.

Soot is most likely from suboptimum combustion or from contaminants in the gas. It means there isn’t a clean burn for some reason.

Never make assumptions. Most tradies will just reinstall the heater, unless one asks for something else.

A gas pre-filter (liquid phase filter or inline vapour filter) isn’t mandatory nor something which is automatically installed. It works a bit like a cartridge filter installed below a kitchen sink, to remove impurities before the water exits the tap. Cartridge water filters aren’t mandatory, but, one can chose to have their fitment. Likewise a gas pre-filter. It won’t be installed unless requested or if a gas plumber recommends it on determining there is downstream sources of contamination which impact on the gas appliance. Hence the advice in my last post.

1 Like
11

The other thing that should be checked is the injector is the right type for the gas supply. LPG (typically bottled gas) and natural gas (typically reticulated gas) need different gas injectors. Many gas appliances come with both as they are interchangeable based on the type of gas used. Using the wrong type can cause yellow flames and potentially ‘soot’.

If the wrong injector (noting they are also called ‘jets’) is used, then this is an installer issue and one could seek reimbursement for any service fees post install.

12

Thanks – will pass on both of these things to check to my friend, the customer.

I think the person who came on Monday (Bosch authorised) was different than the installer, I think….. (I’ll ask.)

If they were different plumbers – they might have checked the jet/injector & detected an error (if there was one). (Or if the original installer – ‘double checked’ that they have the correct jet….)

Below (gas pre-filter) would be another $340 to install? Would hope that the ‘troubleshooter’ who comes out (after two ‘fails’) would think about this – although of course, might not be aware of gas problems – but my friend talks with her neighbours and no one else has mentioned issues with their gas supply or similar appliances being affected by ‘downstream sources of contamination’.

Thanks again – when the problem is rectified (fingers crossed) I will provide feedback here.

2 Likes
13

That would be terrific. It is very hard to work out the problem is. It could genuinely be spiders, but, I find it strange spiders would be attracted to a hot flame to do a kamikaze. Hence trying to troubleshoot for you/your friend, if it isn’t a spider.

14

I agree! Thank you.

15

I think I’d be getting a different plumber in to check that both gas line and appliance were installed correctly and that the water pressure is within the specified range for the appliance. Too high or too low would cause problems.

1 Like
16

ProductReview doesn’t seem encouraging …

17

YIKES!!! Will send the link to my friend…. Mark_M said he had a Bosch hot water heater for ten years – but not sure of the model – whether a Hydropower….

18

But she has one now…. no idea who recommended it to her… Will send her the Reviews anyway…. they are a mixed bag – some old reviews, some new, some different models – but good info to consider…

Thank you.

19

I noticed several of the ProductReview comments were saying there’d been no problems with an older version, but the new one was nothing but trouble.

I hope your friend can either get it working or get a refund for what sounds like it could be an unfit-for-purpose product.

20

It’s a Bosch Highflow 26e mains electricity powered unit. It uses a powered fan to improve efficiency and the ventilation air flow for the burner. In that respect different to the 10H HydoPower. However they all have an air inlet and high level exhaust opening.

We live in a natural bush setting. The house is spider heaven. Perhaps our spiders are different, as the HWS is one of the few places they seem not to bother. One could imagine the inlet which is away from the hot flame is relatively cool. It might offer a place for ants, mud wasps or perhas even spiders. It’s difficult to visualise how a spider can cause sufficient blockage to the air inlet - at least in the model we have where there is a fan induced draft. The Hydropower however relies on natural convection of the hot gases to draw air in. So it may be more readily inhabited and blocked.

The temperature of the exhaust gases is likely to discourage any temporary residents in the discharge.

To also note that the alternate nozzle/jet if incorrectly an LPG option will have a smaller orifice compared to reticulated natural gas. Hence produce less heat. One would still expect it to burn clean and blue, similar to how a gas cook top burner flame always burns blue whether turned right down or on max. That observation suggests that even if there is a problem related to insufficient gas at the burner, a yellow flame would be unlikely. To further suggest that a lack of oxygen in the 10H model could be due to a restriction anywhere in the air pathway. IE All the way through the HWS from the inlet to the discharge ducting including the shrouding around the heat exchanger.

There have been various suggestions as to why the unit mentioned may not be functioning as expected. When one is relying on passed on observations it is possible for something that is important to have been overlooked in the information shared.

A previous neighbour who professionally installed one of the competing brands products (equivalent to our Bosch) on his own property had nothing poor to say about either. OTOH when we purchased our Bosch and asked around about the models that did not require a mains power connection - we found those in the trade were not keen to recommend the battery or water powered alternatives.

Please note that the 10H is a maximum 10l/min delivery flow rate. Depending on the household, supply water temperature and home owners assessment of how hot the water is at the tap, the units performance may not meet their expectations. Our chosen model is designed to supply up to 26/pm. However on a colder day and with the household tank water equally chilled it just meets the needs of two outlets fully on at the maximum temperature. 50C or 55C depending on regulation. Total flow of approx 12-16lpm

NOTE for the 10H model being discussed.
Maximum Flow at 25C water temperature rise: 10 L/min
Maximum Flow at 50C water temperature rise: 5 L/min
Maximum outlet water temperature 50-55C

1 Like