Plumbing Explained
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1. Scale Reducing Devises (electronic)
2. Thermostatic Radiator Valves (TRVs)
3. Immersion Heaters
4. Room Thermostats (A.K.A. Roomstats)
5. Cylinder Thermostats (A.K.A. Tankstats)
6. Combination Boilers (A.K.A Combi Boilers)
7. System Boilers
8. Open Vent Boilers (traditional type)
9. Unvented Hot Water Systems
1. Scale Reducing Devices (electronic)
These devices come in a range of shapes and makes but the basic principles are generally the same and work by omitting a range of high frequency signals into the water which are controlled through a micro-chip. This process imparts energy at a molecular level into the water so that the greater amounts of salts are in suspension in the water within the pipe to help prevent lime scale.
These devices can also encourage existing lime scale to dissolve.
Another very good point with these devices is that they only cost a few pence a week to run, but on the negative side they do wear out between 7-10 years so a replacement will be needed to continue the protection of your water supplied and stored.
2. Thermostatical Radiator Valves (TRVs)
What are they? What do they do?
A thermostatical radiator valve is a very simple device which has a very big role in energy saving. It is basically a local area thermostat designed to aid in keeping the area around the TRV at your desired temperature set on the TRV head. So in essence it is aiding the room temperature keeping it consistent and not getting to hot and wasting energy, as well as making the room easier to control to your personal comfort temperature for that room.
The workings are very simply which makes them highly reliable. One thing to be cautious of is trying to keep the area around the TRV free to allow for air movement so the TRV is as accurate to the room temperature as possible. For example, if there is a long curtain draped over the TRV there will be no air circulating around the valve and behind the curtain will get stuffy and the TRV will react accordingly reducing the radiator heat out-put even though the room may not be at the desired temperature.
ENERGY SAVING CAN BE MADE WITH THE FITTING OF TRV'S!
3. Immersion Heaters
An immersion heater has a very simple role. It basically is an electrical element immerged into the hot water cylinder water normally at the top or bottom of the cylinder and heats up in the water just like an element in a kettle does but on a much larger scale.
The immersion heater is then controller by a thermostat so the water doesn't reach excessive temperatures.
Generally in the UK immersion heaters are a back up incase the boiler ever broke down so at least you could have some stored hot water for showers etc. One thing to bear in mind though is unless the immersion heater is on economy 7 they are a very expensive way to heat your hot water.
4. Room Thermostats (A.K.A. Roomstats)
A roomstat is something that every heating system should have to control the 'call of heat' into the house and it is usually that square box with a temperature dial in your hall or lounge that you turn up when you are cold.
In the interest of saving energy and allowing the roomstat to work correctly it is very important to allow plenty of free air movement around the roomstat. It is also not a bad idea to have it replaced every 10-15 years as they can quote often become inaccurate. Better still and most likely to save you more energy is to install intelligent digital programmable roomstat which has far greater accuracy and the ability to set up time zones through out the day or night with target temperatures, for example:
1. 8am - 20 degrees centigrade
2. 1pm - 21 degrees centigrade
3. 9pm - 18 degrees centigrade
So you can set the temperaturesto suit you at different times of the day and it will do it automatically for you with no adjustment required from you. (This is as long as your heating system worked well before, when heating the house. This won't make radiators hottter or better heat out-put, it just controls the on-off and inbetween).
5. Cylinder Thermostats (A.K.A. Tankstats)
Tankstats is a device that sits on the hot water cylinder usually 2/3 to 3/4's of the way down and are cut into the insulating foam and held in place by a strap (on low pressure hot water cylinders) or are a boxed unit or completely consealed (on an unvented hot water cylinder).
The basic purpose of the tankstat is to monitor the temperature within the hot water cylinder. When the temperature is below its set temperature it will 'call for heat' to the cylinder to reheat the water to the desired temperature. That's basically it - nothing over complicated about it, but just like a roomstat it is not a bad idea to replace these every 5-10 years to be sure of its accuracy.
Look in helpful hints to see what temperature your tankstat should be at.
6. Combination Boilers (A.K.A. Combi Boilers)
Combi boilers are fast becoming the preferred method ofr hot water supply and central heating in small houses and flat. Long gone are the days years ago when combi boilers had a reputation for unreliability and poor hot water heating performance. These days combi's are 'generally' very trust-worthy and economical, there are downsides though............. with combi boilers like many things, cheaper is not better due to older technologies and methods of controls found in older combis, unfortunately some manufacturers have not moved forward much.
One of the best benefits of the combi boiler is its space saving ability, and domestic hot water heater and central heating boiler all in one boiler casing. So there is no need for a hot water cylinder or a tank in the loft. As the combi boiler is supplied directly (generally) from the water mains coming in from the street. But the 3 big disadvantages of the combi boiler are:
- No airing cupboard.
- If the combi breaks down, you most of the time lose both the hot water and central heating.
- Limited flow rates of hot water supply (litres per minutes) multi tap use pressure/flow drops.
So what is a combi then? Simply put, it is an instantaneous hot water heater that heats up hot water from cold while you use it. Also when required (in winter) it will heat up the water in the central heating system to keep your radiators nice and warm, which in turn keeps your house nice and warm.
7. System Boilers
A system boiler is what it sounds like. It is a boiler with a large proportion of the heating system components inside (for a sealed system) like pump, filling loop, expansion vessel etc. System boilers are great if you are limited on space but still want a hot water cylinder (or don't like combi's).
System boilers are great for their applications but the one major drawback, I believe, is that as each heating system is unique in it's own way, a system boiler is really designed for specific installation and these installations is perfect. However, it could very easy for a system boiler to be not up to the job or heating system volume could be to great before extra external components would be required.
So careful planning and consideration is required for a system boiler to be at its best.
8. Open Vent Boilers (traditional type)
An open vent boiler is more of a traditional boiler as it is designed for use on a traditional heating system which has the small feed and expansion tank usually found in the loft. This system is a low pressure system as its pressure is supplied by the head of pressure from the tank and the water in the system is usually circulated by a pump.
As far as the boiler itself there is concern they are 'traditional' but that is not the case as they generally use the same technology as sealed boiler (System Boilers) and Combi's on the burner. But when it comes to the internals they are very simple (and as we all know simple = reliable) as there are very few internal components, just the stuff to heat the water up.
Most modern open vent boilers can be used on a new sealed system (as long as the manufacturers states so) with the external components making the circulation and safety features happen.