Hi everyone,
I’ve just assessed a top floor penthouse with what’s best described as Sod poor water pressure (1 bar standing, 0.25bar working) at 8/9 lmin... it has a conventional heat only boiler and cylinder in the utility, cold water storage and CH feed tank are about 3m higher in a stairwell to a roof terrace. There is about a 50m U shaped horizontal pipe run between the utility and storage tank / feed tank. There is an unmeasurably small amount of water flow at the float valves into these tanks at the best of times (float valves are new). Obviously caused by not enough pressure for the height of the building and a lot of restriction through the long 50m horizontal pipe run.
Another matter is that a previous engineer has been unable to refill the system following draining down to replace a zone valve, so the horizontal pipe run is more than likely air locked without an AAV in the ceiling void to vent. To top it all off all the walls and floors are beautifully tiled, some with engineered wood etc, lovely finish everywhere, ceilings included, no access hatches anywhere - you get the picture.
I’ve installed unvented cylinders a number of times and thats probably half the solution needed here, but it’s going to need a break tank and pump or combined accumulator and pump on the main... I’ve not had to find a solution to this kind of problem before, I was wondering if any other heating engineers have and what specification you would go with?
I also think the CH system needs to be switched to a sealed system, all the CH pipes are run in the ceiling and drop down, would be easier to clear air in a sealed system... or maybe a few AAVs in the ceiling void would be ok with the open vent boiler... what do other heating engineers think?
thanks, Lee.
I’ve just assessed a top floor penthouse with what’s best described as Sod poor water pressure (1 bar standing, 0.25bar working) at 8/9 lmin... it has a conventional heat only boiler and cylinder in the utility, cold water storage and CH feed tank are about 3m higher in a stairwell to a roof terrace. There is about a 50m U shaped horizontal pipe run between the utility and storage tank / feed tank. There is an unmeasurably small amount of water flow at the float valves into these tanks at the best of times (float valves are new). Obviously caused by not enough pressure for the height of the building and a lot of restriction through the long 50m horizontal pipe run.
Another matter is that a previous engineer has been unable to refill the system following draining down to replace a zone valve, so the horizontal pipe run is more than likely air locked without an AAV in the ceiling void to vent. To top it all off all the walls and floors are beautifully tiled, some with engineered wood etc, lovely finish everywhere, ceilings included, no access hatches anywhere - you get the picture.
I’ve installed unvented cylinders a number of times and thats probably half the solution needed here, but it’s going to need a break tank and pump or combined accumulator and pump on the main... I’ve not had to find a solution to this kind of problem before, I was wondering if any other heating engineers have and what specification you would go with?
I also think the CH system needs to be switched to a sealed system, all the CH pipes are run in the ceiling and drop down, would be easier to clear air in a sealed system... or maybe a few AAVs in the ceiling void would be ok with the open vent boiler... what do other heating engineers think?
thanks, Lee.
