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I recently wired a new heating system (someone else did the plumbing)
It is a Gledhill thermal store cylinder heated by both an oil boiler and a wood burning stove. All the heating side of it is working fine.
The problem is the hot water. This tank uses a heat exchanger and a pump to draw heat from the tank to heat the domestic hot water as it passes through the plate heat exchanger. All the electrician has to do with this bit is provide 230V power to a control box supplied with the cylinder.
Well it does not work, and the manufacturer is being slow, seeming to want to follow a fault find by random part swapping policy. And the customer is losing patience.
So I am wondering if anyone understands a bit more about how these work.
There is a Wilo variable speed pump (2 inputs power and PWM speed signal) a water flow switch and another unknown sensor on the cold water in to the heat exchanger.
When a hot tap is turned on, a relay on the control board goes click, the green light on the pump comes on and for a second or 2 noise is heard suggesting the pump starts, but it almost immediately stops, shortly after the green light goes out and becomes a brief flash of the green light every few seconds.
So the pump is not pumping so no hot water drawn from the cylinder into the heat exchanger. The flow switch must work as the relay clicks and that provides power to the pump. I guess my immediate question is what is this other sensor? Cold water in pressure? It's a small cylindrical sensor silver in colour 2 wires connect it to the control board.
The manufacturer seems bogged down trying to blame the plumbing and air locks but both me and the plumber cannot see how that is the case, particularly as where they suspect an air lock is a pre plumbed part of the cylinder.
Any ideas? we keep thinking this should be simple, we must be missing something so obvious we have not checked it.
It is a Gledhill thermal store cylinder heated by both an oil boiler and a wood burning stove. All the heating side of it is working fine.
The problem is the hot water. This tank uses a heat exchanger and a pump to draw heat from the tank to heat the domestic hot water as it passes through the plate heat exchanger. All the electrician has to do with this bit is provide 230V power to a control box supplied with the cylinder.
Well it does not work, and the manufacturer is being slow, seeming to want to follow a fault find by random part swapping policy. And the customer is losing patience.
So I am wondering if anyone understands a bit more about how these work.
There is a Wilo variable speed pump (2 inputs power and PWM speed signal) a water flow switch and another unknown sensor on the cold water in to the heat exchanger.
When a hot tap is turned on, a relay on the control board goes click, the green light on the pump comes on and for a second or 2 noise is heard suggesting the pump starts, but it almost immediately stops, shortly after the green light goes out and becomes a brief flash of the green light every few seconds.
So the pump is not pumping so no hot water drawn from the cylinder into the heat exchanger. The flow switch must work as the relay clicks and that provides power to the pump. I guess my immediate question is what is this other sensor? Cold water in pressure? It's a small cylindrical sensor silver in colour 2 wires connect it to the control board.
The manufacturer seems bogged down trying to blame the plumbing and air locks but both me and the plumber cannot see how that is the case, particularly as where they suspect an air lock is a pre plumbed part of the cylinder.
Any ideas? we keep thinking this should be simple, we must be missing something so obvious we have not checked it.
