Boiler problems

Piggles12345

Hi,
I have a Powermax 155x boiler.

When I put the heating on the radiators don't take long to heat up. Then they stay on for a while (until the temperature reaches what the thermostat on the wall is set to?) and then goes off. During this time, the pressure gauge has risen to about 1.8-2. Then the heating will come back on for about 5mins, then go off for a while, then come back on for another 5 mins, etc etc.

I have had an engineer out and he says that this is normal as the boiler only turns itself back on when the boiler has reached the temperature it needs to and comes back on if that temperature drops. Is this right?

The engineer also said that the fact that the pressure goes up whilst the heating is on is irrelevant. Is this also correct?

It appears to me that there is a correlation between the pressure and the boiler turning off, am I mistaken about this?

Please help. Thank you.

Piggles12345

I'm a bit desperate if anyone can help at all....

EliteHeat

Why are you desperate? you have just described a normally working system.

Is there any reason why you didn't believe the engineer?

tanith

Sounds like its working perfectly to me too..

capita_guy

Why are you doubting what you were told?
If you do not trust the Engineer why use him?
Do you ask for other opinions every time you see your Doctor?
System is doing exactly what it should do.

economiser

capita_guy wrote: »

Why are you doubting what you were told?
If you do not trust the Engineer why use him?
Do you ask for other opinions every time you see your Doctor?
System is doing exactly what it should do.

Don't be too hard on Piggles. Nothing wrong with seeking a second opinion. I would certainly seek a second opinion after seeing a doctor if I wasn't confident about his diagnosis. In fact I am due to see another dentist because I am doubtful about his advice that I need an extraction. I get the feeling he sees this as the easy option.

jimbo_the_jetset

When you put the heating on the boiler will fire and heat until a) the room temerature reaches what the room thermostat is set to or b) the boiler heats the heating 'fluid' to it's maximum temperature (~70 deg). The boiler will turn on and off to maintain either a or b temps when heating is set to on.

Maybe the manufacturer of the boiler can answer your question with regard to pressure if you are still unsure?

Steve_PS

I used to be a CORGI engineer and have worked on these boilers; I'll explain rather than just tell you to trust your engineer, however he's right, your system sounds like it is working normally.
When you turn your heating on the boiler will fire up and heat the water in your central heating (CH) system; this water is circulated around your radiators and warms them up. You have 2 thermostats which regulate both the temperature of the water in you system and the air temperature of your house, and these turn the boiler on and off. The boiler has a user controllable thermostat switch which controls the temperature at which you want your CH system water to stay at when running. Lower settings will allow your system to heat up to a lower temperature but will be safer for example with small children in the house i.e. they will not get burnt on very hot radiators. Your house will still heat up to temperature but will do so more slowly than if your boiler stat is set higher. Set it higher and your radiators will get hotter and heat your house quicker. Your CH system is pressurised and sealed. The gauge you talk of indicates the system pressure; when cold it should read 1-1.5 bar, no more. As water expands when it gets hot it also causes a sealed system's pressure to rise, this is why your gauge indicates a pressure increase when your heating is on. This is normal and your CH system has an expansion vessel to 'absorb' the increase.
When your radiators are hot and heat your house, the rise in air temerature this creates is controlled via your room stat. As the room temperature rises above the set level of the stat it switches your boiler off, thus keeping your room temp at the level your stat is set at.
Hope this help you understand what is happening with your boiler.