Posible leak in heating system

indie armada

im looking to find out what the options are for finding a leak in a sealed heating system. thankfully not mine but a friends heating is giving him trouble after the summer when the heating wasnt being used, he says the rads were practically empty. instead of having a pressure reducing valve on the mains inlet in the attic he has a service valve that he has to open to top up the system. when he went to top up the system it took ages to fill and all the rads had to be bled.
he has a pressure gauge in the hotpress that when it goes over 2 bar he has to bleed one of the rads to relieve the pressure. i know very little about heating but i have a sealed heating system with a pressure reducing valve on the mains and ive no problem. he thinks he has a leak due to the rads being empty but no signs around the house are visable. any ideas.

ntpm

indie armada wrote: »

im looking to find out what the options are for finding a leak in a sealed heating system. thankfully not mine but a friends heating is giving him trouble after the summer when the heating wasnt being used, he says the rads were practically empty. instead of having a pressure reducing valve on the mains inlet in the attic he has a service valve that he has to open to top up the system. when he went to top up the system it took ages to fill and all the rads had to be bled.
he has a pressure gauge in the hotpress that when it goes over 2 bar he has to bleed one of the rads to relieve the pressure. i know very little about heating but i have a sealed heating system with a pressure reducing valve on the mains and ive no problem. he thinks he has a leak due to the rads being empty but no signs around the house are visable. any ideas.

A pressure reducing valve stops the chance of overpressuring the system from mains water.
Sealed systems usually run around 1 to 1.5 Bar cold and around 2 Bar when hot.
Your friend does not need to manually vent the pressure. If the pressure was to get too high then the pressure relieve valve in your heating system would release water to reduce.
Any time you vent the system you will introduce a little air which may need to be vented from radiators if the automatic air vents don't vent all the air.


As for a possible leak... needle in hay stack.
If the pressure is dropping on a regular basis and your friend is having to open the valve and top up the system then he will need to get in a plumber or heating engineer to disconnect and issolate piperuns/circuits and pressure test the system.

kerryplumbing

ntpm is quite right - finding a leak is like finding a needle in a haystack - I would propose that the first thing that your friend should do before he calls somebody out would be to see how major the problem is.
The system should be re pressurised to 1.5 bar and then checked periodically to see how quickly the pressure drops. If it is a very small drop the problem could be to sorted by simply installing a leak sealer into the system. If it is big drop then I am afraid that is a different matter!

indie armada

thanks for the replies, the problem is he cant keep the pressure at a constant level, would a pressure reducing valve help him achieve this. if the pressure reducing valve doesnt do this then what keeps the system at a constant pressure, is it the red vessel in the hot press that does this?
he has a pressure relief valve out at the burner at the back door(kerosene type) but hes not sure if its workin propperly as they tend to jam up out here in rush cause of the hard water. thanks again.

Joey the lips

indie armada wrote: »

im looking to find out what the options are for finding a leak in a sealed heating system. thankfully not mine but a friends heating is giving him trouble after the summer when the heating wasnt being used, he says the rads were practically empty. instead of having a pressure reducing valve on the mains inlet in the attic he has a service valve that he has to open to top up the system. when he went to top up the system it took ages to fill and all the rads had to be bled.
he has a pressure gauge in the hotpress that when it goes over 2 bar he has to bleed one of the rads to relieve the pressure. i know very little about heating but i have a sealed heating system with a pressure reducing valve on the mains and ive no problem. he thinks he has a leak due to the rads being empty but no signs around the house are visable. any ideas.

tbh honest with you i will start at the pressure reducing valve. I have always been off the opinion that these should be outlawed. Why... Because a bad plumber can use them to hide leaks and this becomes a very expensive error on the plumbers part...and the expense is usually for you.

In my opinion all sealed heating systems systems should have combi filling loops and of course these should be disconnected afterwards.

As for the leak on your friends it might be a case of isolation.... belive it or not its not unusual to bleed 2 or 3 rads after summer...They just need to keep an eye on it..


edit.... If the pressure is dropping real quick the leak would be obvious...

Carlow52

OP: can u describe house/ circuits/ floor structure/age/piping type (Cu,Fe,PP)
thanks

indie armada

i sort of understand what your saying about the pressure reducing valve, it will compensate for any leaks that might be in a system by topping it up automatically.....i think thats what you mean. when he first went to turn on the heating after the summer it wouldnt stay on and the rads were not getting hot, at this point he realised there was no water in the sytem and opened the feed valve, it then took a long time for the rads to fill and the pressure to show on the gauge, as opposed to just opening the valve for a couple of seconds to top up the system.
also could you give me a quick explanation to combi filling loops

@carlow.......ill do my best. ok from the burner out side the back door the pipes (all copper afaik) go to the hotpress which is downstairs. in the hotpress is the cylinder and the red vessel. there are approx 7/8 rads downstairs. a few years ago he got the attic converted(bungelow) and there are 2 rads up there. i think it was at this time that the red vessel was fitted. there is only one circut and one apt timer. up in the attic where i assume the mains is comes into the circut there is a service valve which is opened to top up the system. in the hotpress on one of the pipes is a pressure gauge which depending on how long the heating is on reads differantly, usually as time goes it get higher. when it gets between 2 and 3bar he bleeds a rad to reduce the pressure.
the pipes are mostly in covered by concrete and the floor would have originally been a pitch pine floor but now the pine is gone and laminate flooring in the living spaces and tile in the bathroom and kitchen. so there is no subfloor that could be hiding a huge leak, there is nowhere really except upwards for water to come and there is no signs of water damage anywhere.

ps sorry about the longwinded post

Joey the lips

http://www.youtube.com/watch?v=bad_jtRMCcQ


Combi filling loop