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Perfect 35 Undersink Instant Water Heater, 3.5KW

Perfect 35 Undersink Instant Water Heater, 3.5KW

Name: Perfect 35 Undersink Instant Water Heater, 3.5KW
Brand: HSD
SKU: 133362
Price: 119.99 GBP
Availability: InStock
Rating: 4.4 (58 reviews)

Perfect 35 Undersink Instant Water Heater, 3.5KW Thumbnail

Perfect 35 Undersink Instant Water Heater, 3.5KW

58 reviews

£119.99 inc VAT

£99.99 exc VAT

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Order now for delivery 24th December

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*UK mainland only

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Returnable until 31st Jan 2025

Returnable until 31st January 2025

Products purchased between 1st November 2024 and 31st December 2024 can be returned until 31st January 2025

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In stock
Warranty: 2 Years
30 day money-back guarantee
Product Code: 133362A
Have a question? Call 0800 091 3171

Perfect 35 Instant Undersink Instant Water Heater - 3.5KW

The latest in water heater design and manufacturing for reliability and durability

This small instant hot water heater uses simple electronics to control water flow and temperature providing a reliable and steady flow of water to a bathroom hand wash sink. It is non vented and has a minimum pressure requirement of 10psi or 0.7 bar.

Low wattage
This low wattage water heater provides hot or warm water for wash basins (if you are looking for a similar unit for a lightly used sink or en suite conversion alongside a pre-installed electric shower, we would recommend the more powerful Perfect 55 water heater that produces hotter water for the same flow rate and hotter water in general).

Designed with space saving in mind
The unit (with its small size) fits under sinks and takes up less space than traditional tank water heaters. If the sink or basin you are using is a distance from your central heating hot water source, we highly recommend using a Perfect water heater. This avoids the need for litres of water to run wastefully whilst you wait for hot water.

Highly efficient

Instant water heaters do not need to needlessly heat up 10-15L of water for only 5L to be used. This unit only heats up the water as it runs through the unit, saving you energy and water compared to traditional undersink water heaters.

Extremely versatile
Compatible with any tap from ordinary through to single or monobloc taps (peak performance is found with a spray tap fitting)
Easy installation with flexible hoses and rubber gaskets for simple connection by a qualified plumber (not supplied)

Not suitable for use with a shower or bath
Cold water inlet temperature during winter based on 15C
Cold water inlet temperature during summer based on 20C
15.2 amps fuse needed

Reviews

Rating 4.4 out of 5 based on 58 reviews.

Page 1

LAP Electracl southwest

Great little water heater

27 May 2024

Anonymous

Perfect 35 delivered promptly. Before purchase I read reviews so wasn't expecting the flow rate of a higher wattage (so 3.5 watt not suitable to washing up, etc). But for my cloak room, this little gem (and it IS very compact) is absolutely ideal, enough flow of really quite hot water - enough for washing hands. Simple instructions and very easy to plumb and wire ("by a professional"). Am considering further purchases for upstairs loo and outside shed. Does what it says on the tin! 5 star!

9 Jan 2024

David tamplin

Great water heater,ideal for wash hand basin.

25 May 2023

Mrs Elaine Barket

Great.Does the job.

20 Feb 2023

Tony Tonelli

Good product

8 Oct 2022

Bazza

Small unit, easy to fit, efficient.

23 Feb 2022

alan collishaw

Nice and compact

1 Mar 2021

Jason

Very helpful lady on the phone who double checked size for me as its going in a confined space. Next day delivery and Impressed with the heaters ease of installation. Untested at time of writing as waiting on sparky to connect up. None the less very nice company to deal with. Recommended.

24 Nov 2020

CollectPlus Customer

Very good service can't comment on the actual heater as still waiting for someone to replace my old one.

2 Nov 2020

Linda Linton

Very good works well

17 Mar 2020

Documents & Instructions

Frequently asked questions

How long to produce 1 litre of hot water I don’t understand flow charts Thank you

This is an instant hot water heater. Once you turn the tap the water will heat up. Depending on the flow rate the temperature ranges from 32 to 48c.

Hi which country makes these water heaters? Thanks

They are manufactured in Poland.

My current under-counter heater is a small storage unit with a ‘sacrificial anode’ which causes discolouration and small particle contamination of the heated water when the input is water from a salt based water softener. Can your heater be used with artificially softened water?

Yes, they can as they do not operate in temperatures so high as to cause particle separation, where stored water heaters are bound to operate in temps above 55* to combat legionella. The Perfect 35 work like an electric shower, so heat water as it passes through, when you turn on the tap, and only reach temps in the high 30/mid 40s (for the lower powered 3.5 & 4.5kW models. So they are perfect for low duty cycle operation as they deliver warm water on demand but consume zero power when not in use.

You will need to arrange a 16amp power supply.....consult with an electrician.

Hi, how long can you run water through the tap? ie If I wanted to fill a 20 liter bucket, would that be possible?

No, it would struggle to fill a 20L bucket and keep the temperature.

We would recommend a 30L unvented water heater

https://www.hygienesuppliesdirect.com/products/prod107632-30ltr-3kw-unvented-water-heater

Hi, we only have a immersion heater for hot water which we turn on for showers ect, it's to expensive to run all the time for general hot water use. Can one of these be connected to the hot feed pipe that goes to the hot tap. The water is always cold as the immersion is always switched off. Thanks 8n advance Trevor.

No, this is not suitable to be used with an immersion heater.

This requires a cold water feed and is suitable for a cloakroom basin.

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

What is the best continuous flow rate at temperature of 40 degrees of the model 35 please

Approximately in winter 2l per minute and in summer 2.5l per minute water flow rate.

Instruction manual

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

Hi can this be used in a catering trailer for a hand basin, water pumped from a water storage tank to the unit

You would require a minimum of 1 bar of water pressure or 10psi. This will also require electricity from your generator.

Hi, I am looking to purchase your 35 under sink water heater. Is it possible to use a Y hose on this product, so that it can feed two wash basins next to each other (they won’t necessary be used at the same time, but I need hot water to both sinks and can’t afford to buy two water heaters.)

We do not recommend using this with 2 sinks. This is only suitable for a cloakroom sink.

Can you connect this water heater to two sets of taps? I need hot water for a sink and the handwashing sink right next to it.

We would always recommend using one per cloakroom sink.

Would this be for me i live in a 1 bedroom all electric flat , looking to put this under my kitchen sink primarily to wash up .

No, but For a kitchen sink for light use the Perfect 55 would be suitable.

Can I run this model heater on 2.5 mm spar socket

This requires a 15.2 amp fuse. It must be fitted using a qualified tradesperson.

Instalation instructions

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

Does this heater need special connection to the electricity supply, or can it run on a normal plug? Also, when you say small wash basin, how small is small?

This unit does not come with a plug, it needs to be spurred in and is only for hand wash.

Hello we have previously bought vented units because installation is very simple and no specialist accessories are needed, can you tell me if this unit needs an external pipe for any water to drip from, also does this unit come with all the parts necessa

The unit doesn't need an overflow pipe just a mains feed and a pipe to the tap. Unfortunately the tap is not included however everything else is installed.

Can this unit be spurred off ring main and and would you be able to provide hot water for two basins next to each other

As the unit is above 3KW it needs thicker cable than standard ring main.

Hi, need to install 3 underbasin water heatesr for handwashing, but the locactions are in the middle of a large building. We cannot install safety release pipes as required by 'storage' type heaters. Am i right in understanding that these units are 'on-

These units are fine for hand washing and require no external drain.

Can this unit be fitted be upside down (with the inlet and outlet pipes facing down)?

This unit can not be fitted upside down for safety reasons as it has a flow switch that would not work if fitted up side down.

I have 8 bar water pressure where I live can I fit this with a pressure reducing valve to bring it inline with the max of 6.5. Thanks Alan

The heaters will tolerate a water pressure of up to 10bar, so 8 will be OK. you can install a pressure reducer but not within 1 meter of the heater to allow for any backpressure relief from the heater.

Is the water temperature hot enough for washing up dishes, etc? Is the maximum temperature adjustable? What output temperature is normal?

The temperature of the water is hot enough to wash up dishes however the maximum temperature can not be adjusted. Please click on the PDF attached to the product for the temperature rates as this depends on the flow rates.

Hi Can I use Perfect 50 to supply kitchen sink and bathroom basin in a small flat. ???

You would need one water heater per sink.

Can this heater be employed under a sink in a wet room where it will be within splash range of a shower?

This unit has an IP rating of IP24. You will have to contact your electrician to see what Zone this will be plumbed into for your personal circumstances and he will advise if this will be suitable for your needs.

Does it come with full fitting instructions, having not fitted one before.

This unit does have full instructions however it will require a qualified tradesperson to fit the unit due to the manufacturer warranty.

Installed a perfect 3500 water heater earlier this year but it's stopped working. Power is reaching the unit and the light comes on when you run the tap but no hot water. Have checked the flow. Is there a reset for the element ? Cheers

If you could please check the following:
- is the voltage too low (supplying installatio overloaded)
- the temperature of the entering water may be too low.
- water flow too high.

If these do not assist in this matter please contact our Customer Services team on 08000 913171

Can this unit be fed to the mains hot water feed

No this is because the heaters run on full power, raising the water temp according to flow rate based on an entry temp of circa 10-15*. If the entry temp is higher than 20* the water will be super heated and trip the thermal break inside.

Re quick code 133362 3.5 kw instant water heater: 1) Does it need a special venting tap? (ie not an ordinary one) 2) Does it have hot maintained storage ie does it need 24/7 thermostat controlled trickle feed electric power? Many thanks. Stuart

This is an instant water heater therefore it does not have need a venting tap. This does not store any water; it heats as it goes and is connected to the mains water. For full instruction how to fit the unit please see the PDF attached to the web site.

Can the perfect 35 be connected to standard mixer taps?

The Perfect 35 can be connected to standard mixer taps.

Do the prefect 35 need an expansion vessel

The Perfect 35 Instant Water Heater does not require an expansion vessel.

Do I need a vented tap with the 35 model

The Perfect 35 does not require vented taps and can be used with ordinary non-vented taps.

Hi, is it essential that the tap be fitted with the spray Nozel fitting or can I use it without one or an aerated tap insted?

The spray nozzle is optional but fitting it into the tap will give optimal performance of the water heater.

Hi, I asked this question on Friday / Saturday, but have not had a response. I would appreciate a reply. In answer to someone else's question you said this needs to be run off a spur with a 15.2 amp fuse. I can't find a a fused spur, with a suitable fuse

We do not stock 15.2amp fused spurs and we would advise you to contact a qualified electrician to install the water heater correctly.

Can you use this for a shower for dogs i.e control temperture

Although we have customers who purchase the Perfect 55 water heater (our code 133365) for hair salons, we cannot recommend this to wash your dog, since this product is not designed for that purpose. The temperature of the hot water is controlled by the flow rate of the incoming cold water and can be variable.

Will the cable from a 3kw immersion heater be sufficient to operate the heater.?

We would not recommend to use the cable from a 3kw immersion heater. The 3.5kw water heater will need the correct current with a fuse of 15.2amps. As with any electrical appliance of this nature, we would recommend to have the water heater installed by a qualified electrician/plumber.

What are the dimensions of the Perfect 35 unit ?

The dimensions are H 15 x D 7.5 x W 13.5cm.

Can these units be used with a basin TMV (Thermostatic Mixing Valve) ?

This product cannot be used with a Thermostatic Mixing Valve.

1) Does Perfect 35 Undersink Instant Water Heater require expansion vessel? 2) Is this unit suitable to fit more than one wash handbasin/s?

This water heater is an instantaneous water heater and does not need an expansion vessel. It is suitable to provide water to one hand wash basin only for optimum performance.

Does a low mains water pressure of 1.5 bar affect the working of the unit? Are spray nozzles in the tap used necessary for some reason?

This water heater can run on a minimum of 0.7 bar of water pressure, so 1.5 bar would be okay. The spray tap fitting provided ensures peak performance from the water heater.

Hi is it possible to install this in a room away from the sink ie in a cuboard approx 1.5m away from where the sink will be located?

Yes, but there may be a run off of cold water out of the length of piping. If the heater is not used for longer periods, the water in the 1.5m piping will cool, so when the hot water tap is turned on it will have to drain the cold water in the pipe.

Just purchased a "35" unit. Being installed under in cupboard under sink in small cloakroom. Can the 20 amp water heater box be fitted close to heater, i.e. In cupboard or does it have to be fitted outside? Many thanks

As long as the 20 amp fuse box is sealed and accessible, it can be installed anywhere on the circuit. However, a qualified electrician will have better advise on your particular circumstances.

Can inlet to the 35 Unit be fed from the domestic hot water system or will the pressure be too low?

This is a cold feed only water heater, working from the mains water pressure.

Do you need a expansion vessel and blow off for unit

No, this water heater does not need an expansion vessel or a blow off valve.

Can this unit be fitted with the supply & feed at the bottom?

Unfortunately, this water heater cannot be fitted with the supply and feed at the bottom. However, if you are looking for an over sink water heater, the Perfect Mix would be suitable. It comes supplied with a spout which is ideal for a hand wash basin. Please see details below:

https://www.hygienesuppliesdirect.com/perfect-mix-electric-over-sink-instant-water-heater

Can this unit be fitted upside down with the feed & supply at the bottom?

This water heater cannot be fitted upside down. It must be installed the correct way up, with the water connections on top of the unit.

I am in need of hand wash water supply to fit in vanity unit but without plumbing needed. can you help

This unit does not come with a plug, it needs to be spurred in and is only for hand wash.
Please see the link below to the instructions :
https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

Would this unit perfect 35 work in a touring caravan for hot water supply.

This would be suitable for light use hand wash not for a 15L Kitchen sink or heavy use. A 16amp RCD breaker is required. This must be fitted by a qualified tradesperson.

Please see instructions and documents below

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_water_heater_temperature_&_flow_chart.pdf

Will this 35 heater work off a standard ring main, as the ring main is 2.5mm cable off a 20 amp fuse, regards

The 3.5kw unit is rated at 15.2amps and requires a 16amp RCD breaker - 1.5mm cable.

This unit seems small enough to conceal it within the pedestal of wink basin. Is this possible or is it recommended to be more easily accessible? Also, how long are the pipes supplied with this unit? Could it be fitted below the floor in a basement directly below the sink?

This would be dependant on your pedestal size but can also be installed next to the pedestal. The Perfect 55 is H 15.2 W 13.5 D 7.2cm. If fitted below the basement floor but high on the wall close to the ceiling as possible but this will delay the water. No pipes are supplied with the unit.

This has been installed into a small staffroom bathroom area. Please can you confirm whether this system will need to be checked for legionella each month if it is not used frequently? The temperature for the Perfect 35 says it will only go 53 degrees, but is acceptable for hand washing. Please can you clarify.

No need to check for legionella because the heaters go from hot to cold to hot to cold, etc and don't maintain a temperature. The Perfect 35 goes to 48 degrees which is the anti-scald threshold and the nominal temperature for handwash is 40 degrees.

We are planning to put in a water heater in an unheated shed. In winter would mains water be as warm as 15 degrees? If it is only say 10 degrees or even lower would the water heat well enough?

The main issue is frost protection when..in a basic shed, there will be zero heat, and once frozen the heater will be ruined with no warranty cover and then cause leaking as the insides will be split. The P3500B if installed correctly with 16amp power and flow controlled down to 1.5-2ltrs a minute will raise the incoming water by approx 25* so a 10* incoming will be raised to a lukewarm 35*. Depending on what you require the warm water for will dictate what type of heater you should install. If higher temps and a better flow are required we would recommend a storage heater. They'd still have to drain it down (if possible) in sub-zero conditions or protect it with a low-wattage electric tube heater mounted below it. Tube heaters are very good at producing low-level heat sources to prevent frost & icing.

Hi. I’m looking at buying the Wijas Perfect 3500 to use under a handsink. It says it’s an unvented heater, which somebody tells me means a special qualification is needed to fit it, and it can only be used where there’s an external pipe for the pressure, which we don’t have. I thought that as it’s instantaneous, it could be used anywhere and there was no risk of pressure build-up. Please could you advise? Thanks in advance. Dean

This is an instant water heater and there will be no pressure build up or issue.

Pressure is only and issue with small 10-15 litre storage type water heaters which may need expansion vessels fitting as the hot water expands inside the tanks.

I await delivery of my Perfect 35. How can I download the instructions on PDF

Please see the link below for the instruction manual pdf

https://www.hygienesuppliesdirect.com/files/static/%20perfect%20_pressurized_water_flow_heater_instructions.pdf

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