Hi guys.. Fitted a vaillant 937 combi in place of a vented cylinder and old back boiler. Boiler went in the loft so pipes all went across loft and into cylinder cupboard.
Hot out let tees into a pipe under the floor, as it hit the tee the left hand side is feeding two on suites and the right hand side feeds down stairs outlets.
The prob is hot water is only around 40 odd degs ...
First I checked the gas supply, I have a steady 20 mb at the boiler gas valve when hot water drawing, so now gas inlet probs, no heating probs either.
What I did notice was there was a lot of unusual water movement noise when ever a hot tap was been drawn, more than usual...
In the cupboard there is a gate valve that tees of the cold mains water supply and bends under the floor to the on suites, this I assumed was the cold feeds to the on suites..
I closed this just to see if it had any effect. The noise reduced and the hot water down stairs became extremely improved 65/70 degs..
When I tried the on suites hot supply's they also we're perfect, red hot. But... When I turned on the cold supply's in the on suites they ran at a reduced rate and hot!!! When I then opened the gate valve these cold supply's ran cold but the hot ran Luke warm again....
It's as though cold water is entering the hot supply somewhere in the on suites from the left of the house upstairs...
Is it possible for the concealed shower units to be passing cold through internally to the hot side when another outlet is opened?
Or can mixers taps pass internally to dilute the hot to another outlet?
Where the boiler hot outlet joins the original cylinder outlet it goes to a tee, the pipe from the boiler is very very hot, soon as it hits the tee after it the pipe is cool enough to hold your hand on it. Once this cold gate valve is shut the pipe after the tee becomes extremely hot , too hot to hold , same temp as the part before the tee from the boiler outlet.
Ideas please guys, there's two on suites, both have concealed showers. Both have mixers tap sinks , one has mixer bath tap.
Thanks. A confused gas fitter!!
Hot out let tees into a pipe under the floor, as it hit the tee the left hand side is feeding two on suites and the right hand side feeds down stairs outlets.
The prob is hot water is only around 40 odd degs ...
First I checked the gas supply, I have a steady 20 mb at the boiler gas valve when hot water drawing, so now gas inlet probs, no heating probs either.
What I did notice was there was a lot of unusual water movement noise when ever a hot tap was been drawn, more than usual...
In the cupboard there is a gate valve that tees of the cold mains water supply and bends under the floor to the on suites, this I assumed was the cold feeds to the on suites..
I closed this just to see if it had any effect. The noise reduced and the hot water down stairs became extremely improved 65/70 degs..
When I tried the on suites hot supply's they also we're perfect, red hot. But... When I turned on the cold supply's in the on suites they ran at a reduced rate and hot!!! When I then opened the gate valve these cold supply's ran cold but the hot ran Luke warm again....
It's as though cold water is entering the hot supply somewhere in the on suites from the left of the house upstairs...
Is it possible for the concealed shower units to be passing cold through internally to the hot side when another outlet is opened?
Or can mixers taps pass internally to dilute the hot to another outlet?
Where the boiler hot outlet joins the original cylinder outlet it goes to a tee, the pipe from the boiler is very very hot, soon as it hits the tee after it the pipe is cool enough to hold your hand on it. Once this cold gate valve is shut the pipe after the tee becomes extremely hot , too hot to hold , same temp as the part before the tee from the boiler outlet.
Ideas please guys, there's two on suites, both have concealed showers. Both have mixers tap sinks , one has mixer bath tap.
Thanks. A confused gas fitter!!
