Rinnai Direct Flow Gas Hot Water System

[fisherman]

We have these on rentals, they are the remote temp control models, most around 5-6 years old.

My problem is that the activation for the gas heater only triggers when there is a reasonable flow of water through the hot tap and this could limit the use of water saver shower heads. That is, the water saver shower head may not have sufficient flow to trigger the gas heating.

Does anybody have a fix/suggsetion? Is there an adjustment because I would like to install the watersaver shower heads if at all possible.

 

[Pushka]

We had watersaver shower heads in our PP; and the Rinnai system worked OK with it. We ended up taking out the water saver ring for other reasons, but for a tenant it should be fine!

 

[HeXa]

I'm not sure how the trigger works.... pressure I guess... so perhaps restrict the flow of the water inlet by having a smaller diameter fitting.

But yeah.... they are adjustable,

 

[chrispy]

This same problem was on the ABC in Melbourne yesterday, the plumber's suggestion was to change the pressure relief valve.
Hope that helps

Chris

 

[wylie]

We have that type of gas hot water system and on Tuesday we are having our water audit. I will report back about what he says.

Wylie

 

[fisherman]

Did a test:

- if the temp is set at 41 C the water has to flow higher than 4L/minute to trigger heating. Setting the desired water temp higher (say) at 45 or 50 C still requires a flow rate in excess of 4L/minute for heating to switch on.

- if the water can achieve a higher flow than 4L/minute at the outset the water flow rate can be 'wound back' and the heating continues (at least for the short time of the test).

I researched watersaver shower heads (see link below) and a 'AAA' rated watersaver shower head flows at 9L/minute.

http://www.greenhouse.gov.au/yourhome/technical/fs21.htm

This means that a watersaver shower head should work well on a Rinnae. Maybe the watersaver shower head I tried previously was a generic that did not deliver the correct flow.

As well as having wastefull shower heads the problem is compounded by having ceramic washers that turn full on with a quarter turn (many tenants have told me how much they love the present showers ).

Wylie, could you let me know the outcome of the plumber's visit. I assume you also have also received a 'I vil ask ze questions swine' questionnaire from the Queensland Water Commission to complete.

 

[wylie]

I have not received a questionnaire, but my mother did when she booked several appointments for IPs. I await with interest tomorrows visit as we are spending half the day checking our PPOR and our IPs, so if I was meant to be sent a questionnaire and wasn't, the chap will be twiddling his thumbs for a whole morning.

Red tape ....... If he cannot do the job because someone forgot to send me the forms, I will not be paying.

Wylie

 

[wylie]

After a small hiccup (first appointment at my PPOR at 8am was a no show) I called the IP at 10am to tell them he hadn't shown up at my place, only to find out he was already there. His dispatcher didn't give him his paperwork until after 8.30 which meant it was tricky seeing my appointment was 8am.

No matter, he fitted our PPOR in after the other two IPs which are only a few streets away.

I asked him about our Rinnai and he said it is a common story that you cannot have a low flow shower head with this type of gas heater. We didn't need to change any shower heads because ours were low flow types anyway. He reduced the flow on my son's bathroom tap (which he has already had a whine about LOL) and fixed a leaky garden tap (not used for a long time, but leaky when used).

The pressure coming through our family bathroom shower head was 7.5 litres per minute if it is turned on full bore, which it isn't. The downstairs shower head pushes through 9 litres per minute fully turned on, again, not something we do. He said the shower heads available were 6, 9, and (I think) 12 litres per minute so he didn't change any (I might have those litres wrong, but he definitely said we didn't need any new shower heads.)

The two IPs he did today both had quite poor water pressure, but no complaints ever from tenants. I think both showers used 7 litres per minute fully turned on, so changing was not necessary either place.

Worth $20 per house to know that we are doing all we can as far as our shower heads and taps are concerned. Now to work on number one son, who showers downstairs, and after I am in bed and knows we cannot control the time he is in there. He hasn't quite grasped the four minute shower yet. He is a work in progress. I have (once) gone outside to the gas heater power point and turned it off .... didn't go down too well. Might try that again.

Wylie

 

[fisherman]

Rinnae no problem

wylie

Re your son, I have the tee shirt for that one too.

Re Rinnae, I wrote to the company and haven't got a reply back as yet. However I went ahead and installed a couple of 9L/minute 'Granada' showerheads from Tradelink Plumbing Supplies (in Bris). these are working well and no problems were encounted with water heating (same as reported by Pushka above). These are better shower units at $45 each plus GST.

I installed the units in under 5 mins per unit - just use some vinyl tape on the threads and while you are at it ensure that the hole through the tiles for the shower is bunged up with silastic to stop leaks.

From my testing of Rinnaes (Rinnae 24 model) on natural gas, there should be no problem if the resultant water flow exceeds 4L/minute.

 

[arungounder]

My problem is that the activation for the gas heater only triggers when there is a reasonable flow of water through the hot tap and this could limit the use of water saver shower heads. That is, the water saver shower head may not have sufficient flow to trigger the gas heating.
Does anybody have a fix/suggsetion? Is there an adjustment because I would like to install the watersaver shower heads if at all possible.

I had the same problem with Rinnai 26Ltr Instantanious units. I ordered a water saving shower head from Sydney water web site and worked fine for about a year. When the scales blocked the small holes the water flow slowed down and wife and the old lady started complaining that the hot water only flows when the tap turned on full blast.
Called Rinnai Support and the guy said to check the shower head and the inlet for any blockages. After I replaced an ordinary shower head the problem disappeared instantaniously.......

 

[fisherman]

arungounder

What I have found out so far is that some of the water saving heads are too restrictive (down to maybe 4 L/min) and I think maybe some of the cheaper units could clog easily through corrosion. If the flow is too slow. you could always take the plastic black or orange restrictor out (look inside the showerhead). I think it also helps if there are problems to turn the hot on first to trigger the heater (this is about back pressure).

I wonder if scale deposits are more likely if the water temp is set too high ie close to scald?

Also, the Rinnaes could do with servicing when they get older. This is reasonable and cheap when you consider that we only get 8 years of out modern 'tank' heaters due to corrosion and deposits from water.

Only problem I have at present from the tenants is that they are less satisfied with watersaver heads because they have to move around to get washed whereas the previous heads provided all-over coverage.

When will Queensland make tenants pay for their water use?

 

[ggumpshots]

Did a test:

- if the temp is set at 41 C the water has to flow higher than 4L/minute to trigger heating. Setting the desired water temp higher (say) at 45 or 50 C still requires a flow rate in excess of 4L/minute for heating to switch on.

- if the water can achieve a higher flow than 4L/minute at the outset the water flow rate can be 'wound back' and the heating continues (at least for the short time of the test).

I researched watersaver shower heads (see link below) and a 'AAA' rated watersaver shower head flows at 9L/minute.

http://www.greenhouse.gov.au/yourhome/technical/fs21.htm

This means that a watersaver shower head should work well on a Rinnae. Maybe the watersaver shower head I tried previously was a generic that did not deliver the correct flow.

As well as having wastefull shower heads the problem is compounded by having ceramic washers that turn full on with a quarter turn (many tenants have told me how much they love the present showers ).

Wylie, could you let me know the outcome of the plumber's visit. I assume you also have also received a 'I vil ask ze questions swine' questionnaire from the Queensland Water Commission to complete.

What is the upside and downside of a ceramic washer? Can they replace normal washers or do they need to be associated with particular taps?
I invariably have a problem and call the plumber every 18 moths or 2years with my rental property.
My taps where I live now have never leaked in 10 years

 

[fisherman]

ggumpshots

Kitchen flickmixer taps have ceramic washers. We would be replacing kitchen washers very regularly if they had standard washers.

For comparison, in houses we had built around six years ago and where ceramic washers were used throughout except for the laundry and garden, we have found that no ceramic tap has required servicing except for kitchen flickmixers (the original plumber had installed the cheapest units). The laundry taps have required maintenance often depending on the tenant.

The problem with the standard washers is that some tenants are very hard on fittings, destroying new washers quickly and damaging the seats.

We have the usual turn-on, turn off taps but with ceramic washers in showers, baths and vanities. They work well. I have seen the flickmixer lever type ceramics in showers and vanities but most do not adjust very well and drive you crazy.

I think you can retro fit ceramic spindles to standard taps in good condition but maybe a plumber could comment.

Some say that the ordinary washers are best in renters because they are cheap and easily serviced, however we find that the easily turned ceramics (easy on-off) greatly reduce the cause of damage (ie washer overtightening) and the regularity of plumber visits.

You will have to check the cost of ceramics.