There are a number of heating system faults which could result in no hot water from taps and showers, or cold radiators throughout your home. We have separated this section from boiler breakdowns and repairs as some types of heating system repairs include many external components, separate to the boiler, that can have an effect on your heating and hot water if they begin to malfunction.
Heating system parts often fail in the autumn or winter after long periods of inactivity in the summer months. Your heating should be switched on for an hour at regular intervals throughout the summer to ensure that it still functions correctly.
What are the Main Types of Heating System?
Other than combination boilers, there are two common types of heating systems found in modern homes: S plans and Y plans. The one fundamental difference between the two is that a Y Plan uses one 3-port motorised valve to distribute the heat to your radiators and/or hot water cylinder, while the S plan uses two 2-port motorised valves. Motorised valves (or zone valves) open and close depending on whether you switch on your heating or hot water.
Both S and Y plan systems rely on a system or conventional boiler and a vented or unvented hot water cylinder to supply heating and hot water. Below we have included diagrams of both a Y and S plan system.
Y plans are a slightly outdated system and their main limitation is that they only allow for one central heating zone. S plans can allow for heating systems with multiple zones as their individual 2-port valves can be used to supply heat to each circuit.
Another drawback of the Y plan is that if the 3-port valve fails then the customer will have neither heating nor hot water. This is not true with an S plan, as the heating and hot water are controlled via two separate valves.
These key points make S plans the system of choice for all new installations, however there are still many Y plans in existence and it is important for engineers to know how they work in order to carry out repairs. We will always look for the cheapest and easiest solution for the customer and will not suggest a system upgrade unless absolutely necessary.