Has any one heard of CombiSave

[Bodd]

Has any one heard of CombiSave??

If so does it work and does it last? or does it pack up after 5 minuetes?

Bod

 

[GQuigley67]

Hi. You may be running with your preheat on which means that the boiler is keeping it's self permantly warm. Some Boiler manufacturers have fitted this function due to the problem of the delay of delivering warm water. This function costs you around £75-£150 per annum in gas even when your out. The combisave delivers a similar performance but without the cost.
The low flow rate is 2.5litres per minute is for only around 0-15 seconds, with an average saving of 5-6 litres and around 15 seconds quicker in getting to temperature. The bucket test of a before and after will prove this when one is fitted.
Please wait for the reports from the plumbers/Heating engineers on this Furum.
Cheers

David Furlong

Are you looking to replace the pre-heat function in boilers with this type of product ?

 

[CombiSave]

Hi GQuigley67.

That decision will be with them, they will probably wait and see what the demand is for the CombiSave before they jump in. But it has been designed to be installed during the boiler manufacturing process as it can be supplied with out the multi-angle swivel joints. Also in the drawings for the boiler manufactures the Combisave could be fitted with a by-pass so to give the end user a choice of running with it on or off, a bit like the pre heat.
Cheers

Dave

 

[Gray0689]

So let me get this straight it restricts the flow from on hot till up to temp then releases when up to temp?
What is the mechanical side to it powered or mechanical
What is the service time scale recommended ?

 

[CombiSave]

Hi Gray.
Yes it slows the flow down to 2.5 litres if it is below set temperature of around 44-45 C (but this can be adjusted to suit easily). This then causes the water in the boiler to warm up a lot faster and then the valve gently opens to give full unrestricted flow. There is another plus to the CombiSave and that is that it maintains the outlet temperature so that in the winter on some boilers you won't then get a luke warm flow.
It is mechanical using no power and comes with a 3 year warranty, it's British built by a long established company who made valves and sensors for Rolls Royce engines for Spitfires, Lancaster's Etc and still make things for the MOD.
There is no servicing required and has an expected lifespan of around 20 years.
Cheers

Dave Furlong

 

[ecowarm]

Nice meeting you Dave today, and would just like to pass on the results from the install of a combisave at my mothers house.

Test before the install. At the kitchen tap just under 8l of water flowed into a bucket before the temp reached 40c, the same was recorded at the bath.

After fitting, we tested again and just under 4l of water flowed into the bucket and the water was noticeably hotter quicker getting to 45c.

The combisave had to be adjusted because the brittony se80 would not fire at 2.5l per min. and would have saved more water if it had.

Eco

 

[TC.]

Nice meeting you Dave today, and would just like to pass on the results from the install of a combisave at my mothers house.

Test before the install. At the kitchen tap just under 8l of water flowed into a bucket before the temp reached 40c, the same was recorded at the bath.

After fitting, we tested again and just under 4l of water flowed into the bucket and the water was noticeably hotter quicker getting to 45c.

The combisave had to be adjusted because the brittony se80 would not fire at 2.5l per min. and would have saved more water if it had.

Eco

im impressed with the results already, sounds like a good product

 

[Billy Bob Bob]

TBH i am not no ones heard of a ballofix??????????

 

[ecowarm]

TBH i am not no ones heard of a ballofix??????????

It has a wax cartridge and works like a thermostatic mixer how can a ballofix do that GM as soon as it senses the 45c temp it slowly opens and closes to keep the set temp (ADJUSTABLE) a ballofix can only restrict the flow

 

[Billy Bob Bob]

It has a wax cartridge and works like a thermostatic mixer how can a ballofix do that GM as soon as it senses the 45c temp it slowly opens and closes to keep the set temp (ADJUSTABLE) a ballofix can only restrict the flow

ok fair enough if i get sent a free one i will stick it on the performa at home see how it fairs if it works i will specify it

 

[Puddle]

It has a wax cartridge and works like a thermostatic mixer how can a ballofix do that GM as soon as it senses the 45c temp it slowly opens and closes to keep the set temp (ADJUSTABLE) a ballofix can only restrict the flow

Hi Eco

Is the wax cartridge easy to replace,is the part available,how much is it,out of interest

 

[Billy Bob Bob]

Hi Eco

Is the wax cartridge easy to replace,is the part available,how much is it,out of interest

did you have a nightmare at night puddle,i can see the cold sweats now 2 posts and potterton and wax cartridge mentioned that pumas coming to get ya

 

[ecowarm]

Hi Eco

Is the wax cartridge easy to replace,is the part available,how much is it,out of interest

Dont know Puddle, Dave Furlong may be able to help

 

[kay-jay]

dave has kindly offered to install one at my house next week, so watch this space as there will be another before and after comparison coming soon..............

 

[CombiSave]

Hi Everyone.

Regarding the wax capsules. We've asked the same question about it's life span and this was the answer from the Manufacturers Sales Rep last year. Quote:-

"​Yes, I can offer some advice, interesting that everybody is an expert on wax elements, I'd like to know where his knowledge came from!

Yes, the wax will deteriorate over thousands of cycles (not time), about 80,000min to be exact! Elements have a reduction of stroke over a period of strokes (a long period of time) and are tested in all applications. A conservative life would be around 80,000 but it is not uncommon for 150,000 cycle to be met under endurance. Let's say the tap was used from full cold to hot 10 times a day, every day, that's 22 years!

On top of this they do not just stop working after this time, they actually lose some of the stroke, around 0.4-0.5mm so the element opening is affected, not whether it will work of not. If the stroke is shortened then there could be a reduction in flow for the reduced movement of piston. In this case a user may choose to reset the valve setting for a higher temperature to get greater stroke by increasing the water temperature, therefore over-riding the loss of stroke of the element............or buy a new element.

I hope this adds some meat to the bones for your 'expert'

It's worth adding that as the best, most-qualified producer in the World, Vernet have the best manufacturing facilities to give the best, most accurate and longest lasting performance over the life of the element. Wax mix, wax ingredients (wax and copper powder), process control, calibrating etc etc all lead and contribute to the element quality.

Maybe he is looking at the performance of 'non-Vernet' products".

OK, as you can see he's pretty passionate about his wax capsules. But the CombiSave has an adjuster to compensate for any changes. So we feel that it should have a very long lifespan. It is too early to say that we would sell the capsules separately but if there is a demand and of course, it is a greener thing to do, then I am almost certain that we would do that especially the way the price of Brass is going.
Cheers

Dave

 

[Mrs Tara Plumbi]

Hi. You may be running with your preheat on which means that the boiler is keeping it's self permantly warm. Some Boiler manufacturers have fitted this function due to the problem of the delay of delivering warm water. This function costs you around £75-£150 per annum in gas even when your out. The combisave delivers a similar performance but without the cost.
The low flow rate is 2.5litres per minute is for only around 0-15 seconds, with an average saving of 5-6 litres and around 15 seconds quicker in getting to temperature. The bucket test of a before and after will prove this when one is fitted.
Please wait for the reports from the plumbers/Heating engineers on this Furum.
Cheers

David Furlong

Thanks for your reply to my post, #26, I am not a plumber but I have a science degree, a masters degree, and a Maths A level.
I had read the study on your website and the results of your tests do not support buying this product, but I may have missed something and I am happy to be convinced.

FYI I have a Rehema Advanta plus in my house. We normally fit Worcester Bosch combis. I have lived in houses previously with Vaillant, WB and Baxi combis with no complaint about any of them.

A plumber of heating engineer is not the right person to answer the simple question of whether your product is worth it.
Your website should be able to do that.

Is your product worth it? I see it as a basic maths question and on your website you have a long and detailed Report by Knowles & Green dated 2010 which describes a study based in a test house.
I doubt if many heating engineers are going to read it the report:
1. unnecessarily complicated
2. Does not address the simple question
3. And my reading of it does NOT support buying your product.

The Knowles/Green test had a tap at the end of 7.3 mtr & sjower at the end of 15.5 mtr of 15mm copper pipe. Obviously the water in this pipe is not hot and could be anywhere between hot and room temperature.

There is about 2.5 ltr of cold water standing in the pipe to the shower and just over 1 ltr going to tap. The test was done at various flow rates, note at 6 ltr pm to tap the cold water would take 10 seconds to clear the tap before we get water from the boiler.

In my experience this standing water can be a big inconvenience to people but can be a bigger problem for stored hot water when that store of water is a long way from kitchen tap and only a small amount of hot water might be required for washing up but the tap has to run for a minute before hot water arrives.

Section 3.2 of the report says that in real life hot water is probably useful after a rise of 30 degrees and you are basing your claims for the Combisave on flow rates of just over 9 lpm at the tap and the shower, this seems reasonable to me.

In the Knowles Study (I wish I could cut and past it, but I can’t):
(3.3) at temperatures below 35C combi save restricts to 2.5-2.8 lpm and combisave is ineffective.
And it is quicker to reach a 15C rise without comb save than with it.

Figure 3 seems to show that combisave is making very little difference at low flow rate of 3.7 ltr p m

Figure 4 flow rate 6 lpm 15C rise faster without combisave and at 6 lpm at combisave is not worth it even when you compare 30 degree rise.

When we get to Fig 6 with 9+ ltr pm the report claims Combisave is worth having. A 30 degree rise will be reached about 20 seconds fast with combisave at this flow rate but surely all the other data already given shows that the tap should not be turned on full until required temperature is reached.
Furthermore, quite a lot of the data in this study suggests it would be BETTER not to have combisave and just to turn the tap or shower on low flow rate of between 3 and 6 ltr per minute.

One further point: what is the flow rate of taps & shower in a house? I know typical low flow shower rate is about 9 ltr p m but it can be lower. I don’t know what flow rate is typical for taps but of course if the house has low flow taps throughout then combisave would be useless.

I believe WB & Vaillant dominate the combi market and I expect somewhere in their technical data they can tell us how long it will take any boiler to reach given water temperature rise at a specified flow rate. I think we are talking about seconds. So as I said this a solution for a problem which doesn’t exist. The problem is all the cold water sitting in 15 mtrs of pipe.