What to do when you have heating but no hot water
The solutions available when your heating is functional but your hot water isn’t
Heating But No Hot Water? Have No Fear, CGBS Is Here!
Having no hot water whilst the heating remains functional is a slightly more tricky problem to solve than having no heating but functional hot water. If the issue was the latter it is most likely one of 3 things: the diverter valve, the radiators or the thermostat. Whereas, if the problem is having no hot water but the heating is still operating, the options for what could be causing the dilemma are quite limited. The obvious solution would be the diverter valve, but it could also be a few other factors causing the problem.
A cause which may seem obvious is the system settings on your boiler. The settings may have been adjusted to only have the heating switched on and the hot water off, or the temperature of your hot water could be turned right down so the water output is cold.
If you suspect this may be the case, we recommend referring to the user manual for your model of boiler. You can then cross-reference this with your control panel, to check that both the hot water and heating are switched on for the correct times of day and the temperature settings of the hot water is at an adequate level.
On a boiler system there are many different valves for many different purposes, some of these valves are manually changed into position and others automatically align with your control system.
Over time the electrical components of motorised valves can wear down and leave the valve stuck in a certain position. When this occurs it can restrict or entirely seize the heating output of your system depending which valve is experiencing the problem. The valve most likely to suffer this wear is the diverter valve, this is the valve that controls the output and flow of your hot water and heating. If this valve becomes stuck it may leave the hot water fully open and the heating completely closed, it can also do the opposite of this and leave you with hot water but no heating.
Due to the electrical components of a motorised valve we recommend contacting a qualified professional to fix the issue as it isn’t as simple as screwing on a new valve like some may think. If you suspect that you may need a valve replaced, make sure to call us on 0207 9989 005 and our team can ensure the right valve is installed in the correct manner!
Airlock in pipes
Another problem that may cause you to have no hot water but still have functional heating is when air gets stuck in the system’s pipes. In the event that air has become trapped inside your system, the air can then get lodged inside a pipe which will prevent any water flowing through the pipe in question.
Depending on the location of the airlock you could experience no water coming out of your hot water taps or just cold water. You will need to bleed your system if this is the issue you are having but please note this isn’t the same as bleeding your radiators. It is a much more complex process that we highly recommend contacting a qualified professional to perform. If you do decide to undertake this process yourself please consult your user manual, as well as a tutorial video relevant to the make and model of your boiler. Also bear in mind, if you purge a substantial amount of air or water from your system, you will most likely get low boiler pressure. If this is the case, reading this article on the matter can assist on adjusting the pressure.
Separate immersion cylinder
Some systems have a separate immersion cylinder that provides there hot water and a heat only boiler that provides there heating. If this is the case and you are experiencing the problem of having no hot water whilst your heating remains functional, then it won’t be your boiler that has malfunctioned but your immersion cylinder.
A variety of things could be wrong with your immersion cylinder depending on if it gas or electric, such as a faulty pilot light or other component. We recommend checking if the fuse has blown on your cylinder, this normally means that your immersion needs replacing. In either circumstance have an engineer tend to your property so they can properly diagnose the issue and advise on the correct course of action.
If you have gone through these causes and tried the relevant home remedies, then you probably are going to need a new valve installed. To do so, you will need a professional gas safe engineer to attend your property, find the valve in question and install this equipment. It is actually illegal and also unsafe to carry out work on your boiler system without the correct qualifications so make sure an appropriate professional is found. Feel free to call us at any time using our 24/7 customer service helpline for any questions, or to book an appointment for an engineer to come visit your property and tend to the matter.