the CH nor the hot water is firing. the pressure is below 1 on the gauge.
how do i increase the pressure within the system, and how do i prevent the same thing from happening again in the future?
my combi boiler is not firing up, over the last few weeks the water has been getting colder ,it is not firing up now what could be the problem thanks.
niel fernie, April 2010
the answer to this question is based on a similar boiler but not the same one. the pressure in a combi should be 1.5 bar minimum. the pressure is too low. To increase the pressure you should have a pipe coming off the boiler's cold water feed pipe with a small stop valve fitted like a loop. this pipe coming off should be connected to the heating flow pipe which is a also coming out of the boiler at the bottom. to increase the pressure in the system the idea is to let in more water from the cold water supply pipe into the flow pipe by using the mains pressure. whilst doing this watch the water pressure gauge increase to between 1and 1.5 bar. when the pressure is up stop the flow of water by turning the stop tap on the cold water feed pipe. the boiler should by rights have the correct pressure settings on the front near the pressure gauge. some fitters may not connect the pipe i've described and may fold it in a loop lower down the pipes. to increase the pressure is definitely a diy job so look carefully. the boiler will have a pressure switch and so wont work if it's too low. if low pressure continues suspect a leak.
