Dewhot gas geyser manualHow to get the best out of your geyser

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Hot water output 25~ 6lt 8lt 10lt 12lt 16lt 20Lt

Rated input (KW) 12 16 20 24 32 40

Rated output (KW) 10.8 14.4 18 21.6 28.8 36.8

Gas consumption LPG 0.93 kg/hr 1.24 kg/hr 1.55 kg/hr 1.86 kg/hr 2.65 kg/hr 3.01 kg/hr

Water flow min 180 lt/hr 240 lt/hr 300 lt/hr 320 lt/hr 360 lt/hr 600 lt/hr

Water flow max 360 lt/hr 480 lt/hr 600 lt/hr 720 lt/hr 960 lt/hr 1200 lt/hr

Flue diameter 90 mm 110 mm 110 mm 110 mm 125 mm 126 mm

Dimension (W, H, D) 290*430*130 320*520*150 330*590*150 330*620*150 380*680*180 430*730*180

Packed dimension 350*565*180 385*645*200 395*720*200 395*755*200 436*845*260 485*885*260

Net weight 4.6 kg 6.5 kg 7.2 kg 8.0 kg 11.5 13.2 kg

Gross weight 6 kg 7.5 kg 8.5 kg 9.35 kg 13.5 14.5 kg

Safety devices• Water over heating protection (75oC)• Exhaust over heating (145)• Flame out gas cut off• Low flow cut off• Non return valve• Anti frost protection

Parameters• Gas type, LPG • Gas pressure 2 000-2800 pa• Solenoid lifetime 300,000 times• Water pressure min 0.25 bar• Water pressure max 5.0 bar

Features• Domestic instant water heater with

natural exhaust;• Water gas linked automatic ignition,• No pilot light;• Automatic pulse ignition from two

standard torch batteries;• Stainless steel 310 front panel;• LCD temperature gauge;

• Flame height, gas flow switch;• Temperature, water flow

rate switch;• On & off nob for cold or hot water;• Low water pressure starting;• Water pressure stabilizing design;• Starting indicator light;

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Use Require Temp 6lt 8lt 10lt 12lt 16lt 20lt

Hand Basin 4-8lt/min 35 - 45 √ √ x x x x

Kitchen 4-8lt/min 50 - 55 √ √ x x x x

Shower 5-10lt/min 35 - 42 x √ √ √ x x

Bath 12-20lt/min 48 - 55 x x x √ √ x

Spa/ Jacuzzi 20lt/min 32 -36 x x x x √ √

Q/A – Why can I not use a 20lt to run the whole house

A 20lt unit runs from 20lt/min on the cool setting to 10lt/min on the hot.If you are running 8lt/min then the back pressure will switch off the unit.If you are running 10lt then you must have it on the hot setting or it will cut out.

Choosing the Size of Unit

Choice of Cylinder or Regulator for units

Cylinder

Regulator

Geyser size

6L, 8L 6L, 8L, 10L 6L, 8L, 10L, 12L, 16L

9KG 19KG 48KG

3KG1KG 3KG

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Dewhot gas geyser trouble shooting for customersFaults are either Electical - Flat Batteries, Physical - Flow pressure low or blocked, Mechanical - Damaged or faulty component

Symptom Possible fault Solution

Geyser is totally dead when the water is turned on

1. Batteries are inserted incorrectly2. Batteries are totally flat

• Insert correctly, rear battery must be + down and front battery + up• Replace with a brand new set of good quality batteries such as duracell

Ignitors are firing, but the geyser is not igniting

1. Batteries are too weak to lift and hold the solenoid2. Gas supply is low or not turned on

• Replace with a brand new set of good quality batteries such as duracell• Turn on the gas or replace the bottle

Ignitors are firing, geyser is coming on and going out after a very short time

1. Water inlet may be blocked at the water junction2. The gas regulator may be blocked, particularly if a new

bottle has just been fitted without first cracking the seal and letting a little gas bleed off

• Remove the water inlet pipe and check the sieve is not blocked on the geyser• Change the regulator

Water is flowing through the geyser, the LCD is illuminating but the geyser does not ignite

1. The micro switch is not activating enough to switch the geyser on

2. On-Off switch may be faulty

• Turn the RH knob to the right (clockwise) to increase the pressure and activate the geyser. This maybe experienced where you have low water pressure

• Call your installer

Geyser comes on and after a short time the water comes through cold

1. The geyser temperature is set too high and the addition of any cold water will shut it off, either due to back pressure or the temperature has risen too high and the geyser shuts itself off

• The temperature with the hot water on only must be lowered, by turning down the flame. Do this by turning the LH Knob to the left (anti-clockwise) until the temperature is in the correct range. (refer to the chart on our website for the correct temperature setting; http://www.dewhot.co.za/compare_geysers.pdf

The geyser is igniting loudly 1. The gas may be low or the gas regulator may be faulty • Check gas level in bottle if low change• If still no change, change the regulator

The geyser is noisy when running

1. The water is causing resonance as it flows through the radiator

• Change the flowrate setting, RH knob either slightly to the left or right unit it disappears

My geyser is very hot in the basin and cool for the bath

1. The setting and the use of the geyser needs to be understood

• Please watch the video “how to control the temperature” from the website; http://www.dewhot.co.za/dewhot-videos/

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Cascading

• To run a household with its multiple requirements a solution is to cascade.• Use an 8lt to run a kitchen, a 10lt for the shower and run both to the bath giving

18lt/min. Fit non return valves so that the kitchen and shower can only run off their units

Installation of GasMimimun distances from doors, windows, drains and electrics

Non Return ValveNon Return Valve

8lt

8lt 18lt 10lt

10lt

May be reduced to 300 mm provided that a non combustible roof is installed between the containers and the window

Electrical source of ignition, switchbox, distibution board, motor etc

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21

51

1.5

LPG containers

Airbrick

Forced draught inlet for airconditioner

Outdoor light

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Safety instructions:If you smell gas:• Turn off the gas cock.• Do not operate any electrical switches.• Do not telephone from inside the

danger area.• Open windows and ventilate room.• From outside, call the gas company and

your approved installer.

Do not use or store easily combustible materials in the vicinity of the appliance.

Installation and Operating InstructionsInstallation and servicing of the appliance may only be carried out by a registered gas installer.

The appliance should be regularly maintained in order to ensure that it remains in perfect and safe working order.

If there is a risk of freezing, the appliance must be switched off and drained. If the appliance has not been drained during a cold spell then when it is switched on again check that it produces hot water. If problems occur, contact your installer

FunctionThis water heater is fitted with automatic electronic ignition that provides for easy commissioning. All that is required is to switch on a hot water tap.

The appliance will then ignite automatically as soon as a hot water tap is turned on. The igniters fire (tick, tick, tick sound) the gas solenoid opens (clack sound) and then a second later the burners ignite and the ingniters stop firing. When you switch the water off the gas solenoid closes (faint thud noise).

The appliance is substantially more economical because there is no pilot flame and only remains lit while water flows, thus no further gas is used, in contrast with conventional appliances which have a pilot flame that remains alight permanently.

Air in the gas pipe when the appliance is commissioned must be vented, this can cause ignition failure. In such cases, the hot water tap should be turned off and then on again so that the appliance repeats the ignition cycle. The procedure should be repeated as necessary until the gas pipe is purged of air and ignition is achieved.

1. Chimney2. Flue sensor3. Heat exchanger4. Thermostat5. Temperature Probe6. Base plate7. Impluse8. Impulse bracket9. Ignition pin10. Ignition pin11. Flame sensor pin12. Burner13. Valve left bracket14. Valve right bracket15. Water and Gas valve16. Micro switch17. Battery18. Battert19. Battery box bracket20. Battery box21. Switch off for cold22. Battery indicator23. LED display (Optional

models)24. Front cover25. Adjustment knob26. Adjustment knob

a. Hot water outletb. Gas inletc. Cold water inletd. Flue pipe joint

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