Boilers
Combi Boilers in Surrey
There are various types of boiler on the market, at Surrey Gas and Heating we are usually asked to install Combination boilers or System boilers.
Combi Boiler Heating Systems
Combination boilers, or 'Combi's' are now the most used form of central heating boilers. Most Combi's run on mains pressure water, thus do not require tanks to be placed in the loft. They also eliminate the need for a hot water cylinder as they instantly heat the water when it is needed.
Another benefit with the combi is that, due to it running from the mains water supply, this may mean that you can enjoy a high pressure "power" shower without the need for an additional pump. Combi boilers in Surrey require the least amount of plumbing thus offer a cost saving when installing.
The absence of a storage cylinder means that significant savings on water heating can be made. Although the rate at which hot water is produced may be slightly slower than with a conventional boiler, hot water is nevertheless delivered through your taps or shower head at mains pressure.
In Short...
Benefits of Combi boilers in Surrey:
- By far the cheapest to install.
- Never 'run out of hot water'.
- Save space (loosing hot water-cylinder and tanks)
- Maximum hot water economy (only heating the hot water you use)
- Mains pressure on hot water supply.
- High Central heating efficiency
Problems with combination boilers:
- 'All your eggs in one basket', if the combi breaks down you loose both the central heating and hot water.
- If mains pressure is low, hot water pressure will also be low.
- Only good for one hot water draw-off at a time eg. if hot tap is running at the kitchen sink the shower upstairs will be inadequate.
- No good for loft conversions ( the higher you are the lower the mains pressure).
- Prioritises hot water : combi boilers can only do one job at a time, if hot water is running the central heating cannot run simultaneously.
System Boilers
System boilers come in two types, a vented low pressure and an un-vented high pressure system. Both require a Hot Water cylinder. Vented system boilers require a storage tank but most of the other components are held in the unit itself which means that installation is quicker and cheaper.
Also, the hot primary water is pumped through the system to the radiators and hot water cylinder resulting in a faster response and more economical running costs.
Un-vented system boilers incorporate the equipment necessary to form a sealed system including a pressure relief valve and a pressure gauge, removing the need for a feed and expansion tank.
Boiler Replacement Procedure
Boiler installations can vary greatly between boilers and the specific set up in each house. For a straightforward replacement of a typical combi boiler, we have drawn this check list for a combi boiler supply and installation:
- Drain and remove old Combi Boiler and flue -Supply and fit new combi boiler and flue -Alter existing flow and return pipe-work to the combi boiler as required.
- Make alterations to existing hot and cold water pipes connecting to combi boiler as required.
- Install new combi Boiler condense pipe.
- Upgrade or install new gas pipe as appropriate.
- Install new programmer
- Power-flush the system and introduce inhibitor.
- Connect Electric wiring to the combi boiler as per instructions -
- Issue certificate and notify Gas Safe Register - as per regulations.
- Dispose of the old combi boiler and other rubbish leaving area clean.
Both Combi boilers and System Boilers are now required by Building Regulations to be 'Condensing Boilers', which means that they use all the latent heat previously lost through the flue to heat the water thus maximising its efficiency.
