What are tankless water heaters? Are they beneficial to the home owners? Do they save on energy and bills? What are tankless water heaters pros and cons that you should know about? Let us take a look at all these questions on tankless or on demand water heaters.
So what are on Demand water heaters? As the name suggests these water heaters provide hot water only on demand. Unlike conventional water heaters there is absolutely no pre heating and storage of water. So there is no wastage of hot water and no standby heat losses.
So how do these systems work?
Tankless water heaters do not have any storage tank. When you turn on a tap for hot water what happens is this. When you turn on your tap or faucet the incoming water in the pipe activates the heating system. The heating system can comprise of electric coils or gas burners to do the heating. The heat from these supplies get transferred to the water from the pipe. This method of heat generation is as on need basis or as on demand.
So these heaters are also known as on demand water heaters.
These heaters also do not use a storage tank. They heat water directly on demand. Thus there is no waiting time for you as you need not wait for the tank to fill up with hot water. Plus there is no loss of heat too as there is no storage tank.
Electric or gas burners heat water to a preset temperature which you have selected. The temperature gets monitored by a thermostat in the heating system. These heaters can provide hot water of about 7-15 liters per minute.
The pros and cons of tankless water heaters:
So what are the advantages these heaters provide when compared to conventional systems?
• First of all it saves energy. It needs to heat water only when required. It does not need to heat water and retain the heat from the storage tank. So it can save up to 25% of energy every year.
• With no storage tank this heating system takes up very less space and is apt for small apartments which lack space.
• There is no dearth of hot water supply in tankless water heaters. In conventional systems if the storage tank empties you will have to wait for the tank to fill up with hot water before using the faucet.
• The units are reliable as well as durable. A tankless water heater once installed will last up to 20 years or more. The unit is also reliable providing 2-5 gallons of water on demand with the preset temperature.
On the flip side …
• The installation cost is twice that of conventional systems. You must look at the long term benefits when going for these systems.
• The units are also costly coming to around $700-$1500. Piping and proper venting also need to be done which again are costly affairs.
• Retro fitting can be a headache. This is because these units output a lot of exhaust. So venting needs to be of larger diameter and double walled. Plus gas lines also need to be larger. For electric heating there is a need for additional wiring with multiple circuits. So these issues can be planned for newly built homes but not for existing homes.
• There may be intermittent supply of hot and cold water as water needs to be heated and sent to the pipes. This does not happen in storage tanks as water is already heated and kept.
• In some places installation can be a headache. This is because it is still a new technology and permits can be difficult to get.
So take a look at the pros and cons carefully before going for these systems. When installed, these systems can be even used for BBQ’s, hot tubs, pool rooms, sinks etc.
When installing keep in mind that
• A small water heater cannot supply hot water to the whole home simultaneously. For operating all the appliances of a home go for whole house tankless water heaters or install two or more units.
• If you are going for electrical units then you must consider the appropriate voltage, amp ratings for your home. Circuit breakers will also need to be set up.
• Review all the requirements of gas burner water heaters correctly. A lot of details regarding venting, piping accessories need to be planned for. Go for category 3 stainless steel venting units only.
• When selecting water heaters look at your requirements carefully. Do you want single point application, flow controlled heaters for two points or large whole house unit?
So take a look at your cost estimates and consider your requirements carefully before going for these units. When installing these units hire a contractor who is trustworthy.
He should have proper references and he should be a licensed and qualified plumber. Also look at the local building codes and see if you require a permit for installation. It is also important to get a permit from your municipality for installation. So discuss all these issues with your contractor before installation.
Once installed make sure you read the product manual carefully. Regular water heater maintenance will ensure the life