Jun 25, 20227 min read

Gas Geysers Explained

Updated: Jul 28, 2022

Gas geysers are a great way to generate efficient use of energy to heat your water, and they're becoming increasingly popular in Klerksdorp and Potchefstroom. There are a few things you need to know before you buy one, though.

Here's what you need to know about gas geysers in Klerksdorp and Potchefstroom.

Similar to other things in life it is not a fact that all gas geysers are equal, and indeed there are different types of gas geysers you can find in Klerksdorp ad Potchefstroom, these are as follows:

Battery Ignition gas geysers
Hydro Ignition gas geysers
Geysers that used 220 volt Ac to Ignite the Gas Geyser.

Note: Battery or Hydro Ignition Gas Geysers used either batteries or a Hydro to ignite the gas.

Differences to be aware of between the different geysers and that is commonly referred to as Hydro powered (Entry Level) and Forced powered (Advanced Level)

The Battery and Hydro ignition gas geysers are normally lower priced and there are some important factors to keep in mind with these units, the most important points being as follows: (Source: https://gas-geysers-johannesburg.co.za/)

Entry Level gas geysers are not able to effectively supply sufficient hot water to multiple hot taps operating simultaneously, and also does now work well with mixer taps If someone opens up another tap in the house there is a very good chance your gas Geyser will switch off and you will be left with cold water or no water at all. Forced driven gas geysers can supply hot water to multiple taps.
The entry level gas geysers temperature can only be set at the gas geyser. Meaning if your wife likes to take a hot shower and you like a cooler shower you will have to go to the gas Geyser and manually change the temperature on the gas Geyser.
In homes with three or more people and two or more bathrooms, you will ideally need one medium capacity Entry Level gas geysers per bathroom.Forced driven gas geysers can supply two or more bathrooms simultaneously.
Entry Level gas geysers have limitations in the distances they are able to supply hot water over. This limit is approximately 8m-10m.
Entry Level gas geysers are not recommended for double storey homes, unless the bathrooms & kitchen are all on the ground floor.
Entry Level gas geysers are very sensitive to fluctuating water pressure. This is only a problem in situations where water supply is from a borehole and can be overcome by installing a pressure pump. Forced driven gas geysers can normally accommodate fluctuating water pressure.
Entry Level gas geysers will need to be protected from prevailing winds & rain & will need to have a weather cover fitted & flue pipe fitted (extra costs). - A flue pipe The flue pipe on a gas geyser works in the same way that a chimney pipe does on a fireplace. The flue pipe will draw the CO2 gasses produced by the gas burners out of the geyser, along with excess heat. Without a flue pipe, the CO2 gasses settle over the gas burners & literally smother the flames
Entry Level gas geysers must have a flue pipe (chimney pipe) with cowl (‘Chinese Hat’ which fits on top of the flue pipe). Without this the geyser will overheat & keep switching off. Flue pipes come at an extra charge.
Entry Level gas geysers cannot be connected to a controller (these controllers have the benefit of eliminating temperature fluctuations if someone else turns on another tap, enables more precise temperature controls) The Entry Level gas geysers temperature in most instances can only be altered at the gas geyser.
Entry Level gas geysers cannot detect the cold water temperature coming into the gas geyser to save you money on gas and precious water your forced driven gas geysers can.
Entry Level gas geysers don’t work well if water saver shower heads &/or filters on your taps.
Entry Level gas geysers don’t work well in homes with mixer unit taps. If the cold water is allowed in too fast, it tends to push the hot water back to the gas geyser.The entry level gas geysers registers this as a safety problem and switches itself off particularly annoying for the person in shower at the time ! This does not happen with forced driven gas geysers.
Entry Level gas geysers don’t have freeze protection feature. If the weather goes to minus degrees The Entry Level gas geysers will freeze up and damage the heat exchanger and water pipes. The forced driven gas geysers have freeze protection feature including an electrical element and intermittent firing of the burner to protect the heat exchanger and water pipes from freezing over.
Entry Level gas geysers that use the Hydro Generator Ignition – require no batteries. The Hydro mechanisms are easily damaged by dirt/sand in the water supply.
Entry Level gas geysers that use the Hydro Generator Ignition are very sensitive to water flow not enough water flow and the Hydro Generator Ignition will not ignite the gas geyser.
Entry Level gas geysers normally have a much shorter warranty than Forced Driven geysers, so be sure to ask the question on warranties when purchasing your gas heater.
Entry level geysers do not have electronic control systems, so all of their gas burners all come on at the same time. This means that their gas consumption is the same whether one tap or more are operating.

Should you opt for any of these entry level geysers, the recommended sizes vs application would be as follows:

Recommended Standard/ Manual Geyser Sizes

6l geyser – Kitchen sink or basin only
8l geyser – Kitchen sink & washing machine. Can be used for a shower which is not used very often i.e. spare bathroom but does not give a really adequate volume of hot water for daily use.
10l geyser – Shower.
12l geyser – Minimum size required for a bath.
16l geyser – 1x shower & 1x ‘small’ hot tap (ie basin/ sink) running simultaneously.
20l geyser (Standard Geyser ) – 2x showers/ baths running simultaneously

Advantages of the more advanced Forced Powered Geysers:

Forced Fan gas geysers are extremely gas efficient and have electronic control systems & are able to modulate their gas consumption according to demand for hot water.
Exact water temperature can be pre-programmed.
Forced Fan gas geysers can operate under low water pressure conditions of 1 bar.
Forced Fan Gas Geysers are the only geysers which can successfully supply hot water to upstairs bathrooms.
Automatic stabilisation of fluctuating water pressure.
Forced Fan gas geyser electronic systems ensure sufficient water pressure and temperature for multiple hot water taps operating simultaneously.
Fully weatherproof & do not use flue pipes
Forced Fan Gas Geysers can be connected directly to an existing solar water system as a back-up during cloudy weather/ winter.

Disadvantages of Forced Fan Gas Geysers:

Forced Fan gas geysers cost between two to three times that of a Standard gas geyser.
Forced Fan gas geysers must have electricity to ignite and to operate their electronic controls. Lack of electricity during power failures can be overcome by using a UPS/ Inverter/ Generator at these times.
Forced Fan gas geysers can be run on generator power, however protection against power surges must be installed as this can damage the geyser’s electronic operating systems.

Do Forced Driven Geysers Use Electricity

Yes, Forced Driven Water Heater do use electricity. Usage is minimal approximately 83 watts, if anti frost activated 100 watts But this will make your hot water usage very efficient.Buy using a in built computer to measure the water temperature coming in from the ground water ( municipal water ) and giving you a accurate water temperature that you have set the gas Geyser temperature to. This efficiency will save you on precious water and gas.

Gas Installations

If you're interested in buying a gas geyser, you'll need to have a gas line installed in your home. Gas products that carry the Safe Gas Appliance certificate means they have been tested as safe gas appliances and comply to SABS regulations. All gas installations must carry a CoC for insurance purposes and must be done by professionals, his is very important.

What is a Tankless Gas Geyser?

Tankless Gas geysers are rated by the maximum liters per minute it can handle, and not by a tank/geyser capacity in liters that we are used to when referring to standard geysers. So if you see a 20 liter gas geyser it means that this is a 20 liter per minute gas geyser. It could give you 20 liters of hot water per minute maximum. Remember these are tankless ,no resivoir, it’s hot water on demand as you open the hot water faucet.

Here is a great video from Dewhot showing you how to determine your required flow rate prior to deciding the flowrate of the gas geyser you will require:

Other Points to Remember

One other very important point is that your choice of gas geysers may have water heating temperature limitations if the water flow is set at maximum, as explained in this video below by Dewhot, basically the faster your water runs the less ability the gas geyser will have to heat the water to higher temperatures, this is especially important in winter when the incoming water may be cooler and thus will require greater heating.

Will Gas Geysers Save You Money

Gas geysers are far more efficient than electrical geysers and offer a viable and cost-effective option to have hot water for your home. It has been calculated that the savings on your monthly electricity bill could be cut by as much as 40% by going with gas. Your electrical geyser has been proven to be the highest energy consumer in your home.

Going with a gas geyser makes a lot of sense but what does not make sense is going with a low quality, low cost and illegal installation.

A complete gas geyser installation can cost anywhere from R7500 for entry-level up to R20 000 for more advanced setup and depending on your requirements. Based on average industry rates you should budget for your gas geyser installation as follows: (Note these are indicative prices at time of this article, other factors such as the incresed fuel prices, inflation and other factors will impact these prices considerably)

Gas line installation – R2,500 and up
Plumbing – R2,200 and up
Gas Geyser – R 3,000 to R13,500 depending on your requirements (your installer will make the best recommendation for you)
Gas – 19kg cylinder +/- R950

Here is a great video explaining how a gas heater basically works from Builders Warehouse