L
lost
Hi
I had a worcester bosch 30Si combi boiler installed in February together with a new central heating system -- 5 radiators.
3 radiators (by-pass radiator; kitchen radiator and livingroom radiator) were taken off for decorating. Since they were put back on the pressure guage on the combi has not stayed constant at the 1.2/1.25 bar level it was filled up to.
It dropped to 1 bar a week after the radiators were re-installed. The installer told me that there was probably air in the system which has been dissipated out by the boiler. He topped it up to 1.2 and it dropped to close to 1 bar again a week later.
In addition the transmitter failed to connect with the room thermostat and shut the system down. Bosch engineer came out and replaced the transmitter. I spoke to him about the pressure fluctuation and he said it didn't seem to be anything on the boiler like the PRV etc. He said it was probably a leak in the system. Have looked at all the radiator valves and can't spot anything.
I called the installer who came round and bled one of the radiators while the heating and pump was on. he also topped up the system when the system was on. So i didnt have an accurate pressure level to check against when the heating when off. He said to just wait till the system cooled down and take that pressure reading as my measure. And he said to not use the system and keep an eye on the pressure for a few days.
When the system had cooled down the next morning -- the pressure reading was 1.25. It dropped to about 1.15 - 1.1 over a 3 day period during which the heating was off and very little hot water used (10 min shower each day).
[BTW, before this incidenct, everytime hot water was used, the pressure guage dropped slightly and then came back up to the level it was at when the boiler goes off.]
I assumed this drop of about 0.1-0.15 over a 3 day period was insignificant and began to use the heating again. The first day I used the heating, the pressure rose to about 1.75 and stabilized at 1.2 when cool. After a 10 min shower while the heating was off, the pressure dropped and stabilized to 1.15 when the shower was turned off. When heating was used the second day, it rose to 1.75 and stabilized at about 1.15 when cool. After 10 min shower it stablized back to 1.15. On the third day, when a hot water tap was used (while the heating was off) the pressure dropped and stabilized to 1 when the tap was turned off.
Although these seem to be small changes, compared to what others have reported on this forum, I'm a little worried about the trend of the dropping pressure and the fact that the resting pressure seems to fluctuate between 1.2-1.
I worry about the pressure dropping below 1 so always take action when it gets to 1. I've decided to not top up the system to 1.2 and wait to see if the drops continue to occur as the heating and hot water is used.
I would be grateful if someone could let me know whether this trend is anything to worry about. My questions are:
1. Could it be a leak in the central heating system like the Bosch engineer suggessted.
2. Or are these fluctuations to be expected (although if the pressure continues to drop a little everytime hot water is used...it could add up)?
3. Why does the pressure drop (ie stabilize at a slighlty lower level) after hot water use instead of going back up to 1.2?
4. Or could it be that there is still air in the system that is being gradually dissipated out by the boiler?
I didnt have these pressure fluctuations before the 3 radiators were re-installed.
Incidentally the small by-pass radiator in the hall and the kitchen radiator (a column 2m tall radiator) are not quite straight -- they seem to lean towards one side. I noticed that the bypass radiator does not heat up evenly -- the top corner of lower side is slightly less hot than the other side. the column radiator seems to have even heat. All radiators have TRVs except the by-pass radiator.
Apologies for the lengthy description...wanted to make sure I provided all the info as it has been driving me crazy trying to figure out whether this is a problem that could get worse or whether it's normal.
I would be very grateful for any advice or suggestions you may have to put my out of my misery.
Thanks so much in advance for your help.
I had a worcester bosch 30Si combi boiler installed in February together with a new central heating system -- 5 radiators.
3 radiators (by-pass radiator; kitchen radiator and livingroom radiator) were taken off for decorating. Since they were put back on the pressure guage on the combi has not stayed constant at the 1.2/1.25 bar level it was filled up to.
It dropped to 1 bar a week after the radiators were re-installed. The installer told me that there was probably air in the system which has been dissipated out by the boiler. He topped it up to 1.2 and it dropped to close to 1 bar again a week later.
In addition the transmitter failed to connect with the room thermostat and shut the system down. Bosch engineer came out and replaced the transmitter. I spoke to him about the pressure fluctuation and he said it didn't seem to be anything on the boiler like the PRV etc. He said it was probably a leak in the system. Have looked at all the radiator valves and can't spot anything.
I called the installer who came round and bled one of the radiators while the heating and pump was on. he also topped up the system when the system was on. So i didnt have an accurate pressure level to check against when the heating when off. He said to just wait till the system cooled down and take that pressure reading as my measure. And he said to not use the system and keep an eye on the pressure for a few days.
When the system had cooled down the next morning -- the pressure reading was 1.25. It dropped to about 1.15 - 1.1 over a 3 day period during which the heating was off and very little hot water used (10 min shower each day).
[BTW, before this incidenct, everytime hot water was used, the pressure guage dropped slightly and then came back up to the level it was at when the boiler goes off.]
I assumed this drop of about 0.1-0.15 over a 3 day period was insignificant and began to use the heating again. The first day I used the heating, the pressure rose to about 1.75 and stabilized at 1.2 when cool. After a 10 min shower while the heating was off, the pressure dropped and stabilized to 1.15 when the shower was turned off. When heating was used the second day, it rose to 1.75 and stabilized at about 1.15 when cool. After 10 min shower it stablized back to 1.15. On the third day, when a hot water tap was used (while the heating was off) the pressure dropped and stabilized to 1 when the tap was turned off.
Although these seem to be small changes, compared to what others have reported on this forum, I'm a little worried about the trend of the dropping pressure and the fact that the resting pressure seems to fluctuate between 1.2-1.
I worry about the pressure dropping below 1 so always take action when it gets to 1. I've decided to not top up the system to 1.2 and wait to see if the drops continue to occur as the heating and hot water is used.
I would be grateful if someone could let me know whether this trend is anything to worry about. My questions are:
1. Could it be a leak in the central heating system like the Bosch engineer suggessted.
2. Or are these fluctuations to be expected (although if the pressure continues to drop a little everytime hot water is used...it could add up)?
3. Why does the pressure drop (ie stabilize at a slighlty lower level) after hot water use instead of going back up to 1.2?
4. Or could it be that there is still air in the system that is being gradually dissipated out by the boiler?
I didnt have these pressure fluctuations before the 3 radiators were re-installed.
Incidentally the small by-pass radiator in the hall and the kitchen radiator (a column 2m tall radiator) are not quite straight -- they seem to lean towards one side. I noticed that the bypass radiator does not heat up evenly -- the top corner of lower side is slightly less hot than the other side. the column radiator seems to have even heat. All radiators have TRVs except the by-pass radiator.
Apologies for the lengthy description...wanted to make sure I provided all the info as it has been driving me crazy trying to figure out whether this is a problem that could get worse or whether it's normal.
I would be very grateful for any advice or suggestions you may have to put my out of my misery.
Thanks so much in advance for your help.
