Got a new HWS but I think I stuffed up!

G'day everyone,

My old continuous flow hot water system was doing a crap job (I found out it is a 10L/min 26 years old job) . I decided it was time for a new one and the gasfitter I normally use said go bosch because he has always had good service from them.
So I did some research on some 21L/min systems (we have 2 bathrooms) and then found the deal of the century! a new 26L/min Bosch 26E system with 2 controllers, delivered for $1060. The 21E systems I was pricing were around $1260.

So I paid the money and got the gear, all brand new and in good nic. Then today when the gasfitter came out he said he cannot install it as it is not factory set to 50°C. I would have to have a plumber install a tempering valve first. He says it should have a sticker on it saying it had been programmed to run at this temp.

The guy I brought it off says all Bosch systems come out of factory at 50°C and but have switches inside to heat them up to 60°C or 75°C if need be.

So who is telling the truth? Do I need to get this tempering valve installed and blow the good deal I made? Or has Bosch stuffed up and sent a dodgy HWS?

Any help would be great.

PS: I know the tempering valve is a safety mechanism to prevent scalding which I am all for but I just thought the fancy HWS would do the same job.

Thanks

I am not a plumber, and I am not qualified to do any plumbing.

So that is covered.

At least here in Vic, tempering valves are required by law on all new installations.

When we had our hot water system installed I discussed the issue of a tempering valve with the plumber, wasn't keen on the idea as it works by mixing cold water with the hot water coming out of the HWS (so he tells me). So he suggested that I set the HWS as low as we can get away with. So far that has worked quite well, so no real worries.

He also told me that in a lot of homes he goes to the tempering valve has been bypassed:rolleyes:.

Thanks for the tip big shed, I will see what the gasfitter says.

I did some research and for me to be compliant with the gov standards I need to have some method in place to stop water getting hotter than 50°C. So in my case I have two options:

1. Get a plumber to install a tempering valve or pay more for a thermostatic valve?
2. Get a HWS thats programmed to run at no more than 50°C

So I wonder if Bosch will swap over this HWS for me?

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Originally Posted by JohnJohns

Thanks for the tip big shed, I will see what the gasfitter says.

I did some research and for me to be compliant with the gov standards I need to have some method in place to stop water getting hotter than 50°C. So in my case I have two options:

1. Get a plumber to install a tempering valve or pay more for a thermostatic valve?
2. Get a HWS thats programmed to run at no more than 50°C

So I wonder if Bosch will swap over this HWS for me?

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I would certainly look at a thermostatic valve. Nearly all valves over here are thermostatic and work very well. On the other hand, unless the valve cannot go higher than 50 degrees C , there is the possibility for you to turn it higher if you choose. :)

G'day JJ,
The problem you face with having a HWS set internally at a low temp is that ALL your house gets warm water. With the external mixer it is possible to have your kitchen and laundry etc supplied with 'normal' temp hot water which is an aid to domestic harmony.

Barry Hicks

So how much extra was it to get the tempering valve installed?

Donna

How much to have a tempering valve installed?
Dunno! Mine was installed when the house was built to comply with council building regs. I believe a retro fit could run into big $'s if the line to the bathroom isn't easily accessable.
The fitting is made of brass and looks expensive.

Barry Hicks

Tempering valve = $60-80 (not the Thermostatic kind coz they are $300+)
Labour to install = Varies depending on how hard it is to get your pipes, mine were easy so it would take about 1-2hrs I think.

But guess what...

I broke out the yellowpages and found a plumber who will come out and install the new HWS with a tempering valve on a saturday morning. He is here right now!
He is charging the same as the original gasfitter i was going to use + the cost of buying the tempering valve.

He is placing the tempering valve on the main line out of the HWS so yes, all my hot water will be set to 50°C (this is a lot easier to do) but he says later he can come and either run a new line or detach the existing kitchen sink away from the tempering valve so I can get the 75°C to my kitchen sink. Not too concerned about this really as our dishwasher heats its own water.

In Victoria if you are replacing an existing system then it is my understanding that there is no requirement for a tempering valve if one is not already present.
However since the topic of tempering valves has been raised let me say that I think they are the biggest heap of s%#t that I have ever come across. I had a solar system installed last summer at a cost of over $5500 and it is basically useless, all due to the tempering valve. At the moment the water is 41 Celsius and I wont bore you with all the associated gorey details, but I reckon that even if it could be bumped up to 50, it is still too cold. Somebody might be able to set me straight, but I believe it is just a mechanical device that mixes hot and cold before it gets to my mixer where the same process is repeated. It has no idea how hot the water is that it is mixing, so with a solar system, where the temperature of the water can vary widely depending on the amount of sun received, the temperature of the water coming out of the mixer is anybody's guess. Mine's going west ASAP. That feels better!!!

Well the hot water system is in and the tempering valve is in place and the mess of pipes that was there have all been cleaned up and organised. He also had to rerun 3/4" pipe from the bottles to the HWS as existing 1/2" pipe was not enough. The plumber took 2.5hrs doing it all and charged me under $400 for the lot.

I thought 50°C wouldn't be hot enough but it is plenty hot enough, and compared to our older system its a lot hotter. There is better pressure too, not quite as much as the electric systems I've used with their mains pressure but its a lot better than the old gas system I had.

The tempering valve has been adjusted so I get the full 50°C and when I turn more than one tap on the pressure drops a little but then regains quickly, the heat stays the same. I am sure the system would be a lot better without the tempering valve but the system is still very usable and I can feel all warm and fuzzy that I am being compliant.

Well I owe an apology to the tempering valve people. The plumber was going to come and have a look at the problem (over 100km away) but remembered that the house was incomplete and asked that I check to make sure that there wasn't any chance of hot getting mixed with cold at any non-operational points. Turned out that the shower mixer in an unfiinished bathroom was on. It had a plastic cover over it and a stopper on the outlet so it wasn't obvious that it was on until the cover was removed. Problem solved. What am I going to do with all the compression fittings that I bought to remove the tempering valve. I might keep them as a memento of the 6 months of tepid showers I had to endure.

Mate if its an existing house and a straight swap over with MINIMAL mods to existing pipework, AS3500 states that you do not require a tempering valve unless you SIGNIFICANTLY ALTER the hot water pipework or move the heater to a new location, however, you must check up on local QLD plumbing rules as these rules will supercede the AS3500.

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Originally Posted by Metung

Well I owe an apology to the tempering valve people. The plumber was going to come and have a look at the problem (over 100km away) but remembered that the house was incomplete and asked that I check to make sure that there wasn't any chance of hot getting mixed with cold at any non-operational points. Turned out that the shower mixer in an unfiinished bathroom was on. It had a plastic cover over it and a stopper on the outlet so it wasn't obvious that it was on until the cover was removed. Problem solved. What am I going to do with all the compression fittings that I bought to remove the tempering valve. I might keep them as a memento of the 6 months of tepid showers I had to endure.

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He he he he, its a bitch isnt it! I done a rough in on a reno once and had the lady call me at 9pm cause she had no hot water, capped off the shower breech as normal, a cap in the cold and a spindle in the hot, but forgot to put a washer in the hot spindle so the water was mixing. I was just about in bed and had to drive 45 mins each way!!!!!!!!!!!