jack benson

the pump is inside the water heater which is mounted on the wall. the pump lifts the water from above we do not install any electrics under the shower tray. the water heater has a flow meter inside that detects when the shower is in use and starts the pump

is the shower waste pipe gets blocked you will have a problem showing whether you are using MWHR or not. as long as you power off our heater, it is safe to use normal drain un-blockers. when the pump is off, the water will go down the soil stack as normal

The water leaves the shower floor at about 37 C in this case and we pre-heated the cold water to about 34 C 37C - 7.6C = 29.4C - Temp difference between water leaving the shower tray and the cold water supply 34C - 7.6C = 26.4 C - Temp difference between the pre-heated water and the cold water supply 29.4C * 88% = 25.8 C - therefore the numbers stack up

A French start-up owns the patent and i have spent the last year commercialising the product. We now have a production line up and running in France and a growing install base there. Any advise on how to do this would be appreciated

You are not missing anything, below is the clarification - both sides are 6 lpm. The water flows as follows: CLEAN WATER SIDE There are slight inconsistencies in the flow rates recorded by each sensor, but they should all be the same. MAIN COLD FEED becomes the SHOWER HOT FEED (The cold water is heated by our system from 7.6C to 40C). The MIX FEED is a combination of the SHOWER HOT FEED and SHOWER COLD FEED. In this example, because its winter and the cold water is very cold, the system heats the water to 40 C and does not require mixing with cold water, therefore the SHOWER COLD FEED is 0 lpm Therefore MAIN COLD FEED, SHOWER HOT FEED, MIX FEED are all the same water flows. The Flow rate of the clean water is 6 litres per minute. WASTE WATER SIDE The water that leaves the shower tray is marked as FROM SHOWER TRAY. After it leaves our heat recovery system it is shown as TO SOIL STACK. As this part of the system is pumped, there is some air mixed in with this water which explains why the flow shows at around 6.8/6.7 instead of 6 lpm. To heat 60 litres of water from 7.6C to 40C with no heat recovery would use 2.27 kWh - so i agree your calculations of about 71% saving. But traditional systems have other considerations: Hot water cylinder: You need to factory approx. 15% heat loss from a cylinder or hot water that is left in the pipes after the shower ends. Gas boiler: efficiency can range from 98% (theoretically) to 70%.

This is the type of show I will target in the future. We got a free stand last year at the Installer Show 2023 as we fitted their criteria for innovation - there was supposed to be a dedicated area for innovation - but they sold the space at the last minute and pushed us all to different parts of the hall and it was hard to be visible. Also people were not looking for innovation at that show. I want to try to get a few installs before committing to an exhibition as it is important to have local reference sites.

the next production batch will have an even more efficient heat exchanger which should beat the 88% we achieved in the previous test Measuring the performance of a water heat recovery system - News - CSTB in terms of the pre-heating time - everything in life has friction. if you are used to it then you live with it, if you are not used to it, then the trade-offs needs to be explained. i think having an endless supply of hot water for a family is better than running out of hot water if there is a hot water tank, or if you are trying to get rid of a combi gas boiler and you need to put a large hot water tank for a heat pump, then our solution for showers might be a good option so you don't have to find space for the large water tank. if you are renovating the bathroom then our product should not be complicated to install. if you are not renovating the bathroom then you cannot install it. We are speaking to lots of people. Kohler / Mira recently bought Recoup for example. At the moment our focus is to bring some international sales. if for the UK, faster flow is more important, we can look at a roadmap with a 8 or 10 litre a minute model. and thank-you for your best wishes

it wont start the shower, it will start the pre-heating of the water in our system.

it depends what problem you are trying to solve. If you focus on cost saving and take a short shower, then yes - on that metric it might not be for you. But if you want to have a nice hot shower year round and for whatever reason you cannot at the moment, and you do not want to do major plumbing works on the house, i cannot see any other solution on the market that will give you this shower experience without requiring larger scale works

as part of the patent protection we have an automated cleaning cycle that keeps the heat exchanger clean. yes - but the experience is bad in winter and expensive to run all year. if you want to spend £100 on a shower, we are not for you, but if you are in a house that has issues with hot water, and putting in a bigger cylinder or changing the gas boiler will cost many £1000's, this is a good alternative the building work is limited to the bathroom finally, bring a 40/60 amp supply to the bathroom is expensive. a 20 amp supply should me much cheaper

we have a pre-heat cycle. there is a button that is pressed before the user wants to shower. it takes between 1.5 - 3 mins to pre-heat the water in the system (deepening on the room + cold water temperature) - this is enough to heat the shower cubical / floor etc without experiencing a temp drop in the water. once the shower starts, there is a constant supply of hot water - no waiting you have to when the hot water tank is on the other side of the house. we have a Wifi / Bluetooth app in the works which will enable you to start the pre-heat. in future we plan to add the ability to set times of the day the system will automatically pre-heat itself. at the moment the system is wall mounted. the next production batch will be 500 * 300 * 150 mm in size - not tiny but not massive. it should be as close to the shower as possible to maximise performance.

If we made a 4.5 kW version we could increase the flow rate to a minimum of 8 litres per minute. remember the quoted flow rates are the lowest flow rates when the cold water is at its coldest. In the summer the flow can increase. I want a few reference sites in the UK before investing in trade shows. I think that is going to be important for acceptance. there are many positives - significant energy savings - Tankless design so not standing heat loss - Limitless amount of hot water - does not require an environmental heat source like ASHP or solar thermal panels - small footprint - can easily retrofit - energy cost comparative to gas heated showers - frees up space as large hot water cylinder not required - coupled with solar PV + battery, zero energy cost showers (Solar PV provides a more useful energy source than solar thermal)

yes - either for new builds, bathroom renovations, or adding a bathroom to an existing property. The renovation market is many times larger than the new build market

yes - WWHR has been around for a while, but there is no system on the market that both heats water and recovers heat at the same time. WWHR are normally paired with a hot water cylinder and a lot of heat is lost in the pipes. Either the WWHR is not located near the source of heat, or there is a long pipe run back to the cylinder, or there is a long pipe run from the cylinder to the shower. Our system has been independently tested by the French body for WWHR and we have an 88% efficiency. I am happy to share the data Instant electric showers need a 40 or 60 amp supply, and struggle with flow rates in winter. They are generally designed to have a max cold water inlet temperature of about 25 C, so putting a WWHR device between the shower tray waste outlet and the electric shower is often not possible. Our system only requires a 20 amp supply, and we have a 13 amp version that will have a slightly lower flow rate in winter. I am not saying this system is for everyone, but there are use cases where it provides a better solution than the alternatives. in the UK over 30% of the market is instant electric showers. 6 litres per minute is wishful thinking for half the year. like heat pumps we can reduce reduce energy usage by up to 75%, but we do not need a large water tank or to install anything outside. This is a demonstration of the system working.

we recovery up to 10 kW of energy from the waste water so we can heat water from 7 C to 40 C at 6 litres per minute using between 2.5-3.6 kW of heat (variable output electric heating element to maintain the flow at the correct temperature) without the heat recovery you need a 14 kW heating element to provide the same amount of energy to heat water from 7C to 40 C at 6 litres per minute. the waste heat is recovered from the used shower water and used in real time - so the energy loss in minimal (used shower water is never put back into the shower) the system is specifically designed for showers. This video is from Triton. Their 7.5 kW shower will give 3 litres per minute in winter, and their 10.5 kW shower will give 4.5 litres per minute in winter. using no more than 3.6 kW we can give 6 litres a minute year round at 40 C