My parents have an ongoing problem with their recently installed central heating & hot water system.
It is a vented hot water system and selaed central heating system, and comprises of:
2 x BAXI 100 HE Condensing boilers working in tandem
2 x 250L hot water tanks 450x1500mm (indirect)
50 L Expansion vessel
2 x 100 gallon cold water storage - rising main 22mm (flow rate and pressure unknown)
3 x salamander hot water pumps (mounted in the loft) delivering hot water to the bathrooms and kitchen.
The boilers are mounted in the loft spce, along with the cold water storage tanks and expansion vessel.
The pressure on the heating system drops over a number of days, this has to be constantly topped up to prevent the air reaching the boilers in the loft and them cutting out.
The expansion vessel has been checked for pressure and this is correct, there is no water present at the air refill valve.
there is no water present at the tundish from the PRV's on the boilers, also there is no water present at the system relief valves (there are two of these that drain in to a small tank, that then connects to the overflow after the PRV tundish, which continues to the outside) A bag has been attached to the overflow to test if there is any loss through this, the bag is dry
A very small amount of water has been noticed to be dripping out of the heat exchanger on one of the boilers, but is presently dry.
3 bottles of system sealer have been added to the system to try and prevent system water loss if it is a leak in the CH - however, I have been around the entire house with a moisture meter on walls, floors etc, and there is no sign of damp anywhere - the heating engineer of 40 years states that the system is loosing 5 litres a week when in use. The house is of cast concrete design, with CH pipes laid in floor channels, back filled with loose insulation material.
My questions are:
1. Is there anyway that the water could be leaking in the heat exchangers and being "driven" out by the intense heat here?
2.Is there anyway that the leaks could be internal to one or both of the hot water cylinders? Maybe the coil?
3. There is also a water softener, could this cause any problems in terms of introducing air in to the system?
Any suggestions to this ongoing and annoying problem most welcome!
It is a vented hot water system and selaed central heating system, and comprises of:
2 x BAXI 100 HE Condensing boilers working in tandem
2 x 250L hot water tanks 450x1500mm (indirect)
50 L Expansion vessel
2 x 100 gallon cold water storage - rising main 22mm (flow rate and pressure unknown)
3 x salamander hot water pumps (mounted in the loft) delivering hot water to the bathrooms and kitchen.
The boilers are mounted in the loft spce, along with the cold water storage tanks and expansion vessel.
The pressure on the heating system drops over a number of days, this has to be constantly topped up to prevent the air reaching the boilers in the loft and them cutting out.
The expansion vessel has been checked for pressure and this is correct, there is no water present at the air refill valve.
there is no water present at the tundish from the PRV's on the boilers, also there is no water present at the system relief valves (there are two of these that drain in to a small tank, that then connects to the overflow after the PRV tundish, which continues to the outside) A bag has been attached to the overflow to test if there is any loss through this, the bag is dry
A very small amount of water has been noticed to be dripping out of the heat exchanger on one of the boilers, but is presently dry.
3 bottles of system sealer have been added to the system to try and prevent system water loss if it is a leak in the CH - however, I have been around the entire house with a moisture meter on walls, floors etc, and there is no sign of damp anywhere - the heating engineer of 40 years states that the system is loosing 5 litres a week when in use. The house is of cast concrete design, with CH pipes laid in floor channels, back filled with loose insulation material.
My questions are:
1. Is there anyway that the water could be leaking in the heat exchangers and being "driven" out by the intense heat here?
2.Is there anyway that the leaks could be internal to one or both of the hot water cylinders? Maybe the coil?
3. There is also a water softener, could this cause any problems in terms of introducing air in to the system?
Any suggestions to this ongoing and annoying problem most welcome!
