The Dublin Plumber Blog #23 – Negative Head Booster Pump

This week, the Dublin Area Plumbers team were called out to a residence in Dublin 7 to fix a faulty pressure pump- only to discover a much larger problem. Read more to learn about how a little extra effort can go a long way in the world of plumbing.

The Story.

A  lady in Drumcondra Dublin 7 called us during the week because she had a leak in her hot press. The expansion vessel on the heating system had ruptured and needed to be replaced. In order to replace it the heating system had to be drained down. Once the job was completed and we went about refilling the heating system, we found that we could not get the rad in the attic to fill fully. We soon realised that the heating system was being filled via a pump in the hot press. The pump was a positive head pressure pump which is designed only to boost water pressure below the supply source, ie a tank in the attic. As the rad we were trying to fill was positioned above the water line in the storage tank it simply could not fill. 

After explaining this to the customer she informed us that in the 7 years she had been living in the house the radiator in the attic never heated. She also told us that in order to run her shower she had to flush the toilet first in order to get the pump to run and asked might this be connected. She had been doing this for 7 years and thought this was just the way her plumbing and heating system was designed to work. 

She was delighted when we told her that there was a very simple solution to the issues she was having in both the plumbing and heating systems in her house. We replaced the original positive head booster pump with a 3 bar brass bodied negative head booster pump. This pump is designed to pump water above the supply source, ie over and above attic storage tanks. After installing the new pump the attic rad vented fully an less than a minute. When we opened the shower valve, after an initial splutter, water came rushing out like never before. And guess what, the toilet did not have to be flushed before the shower worked. 

One simple plumbing correction completely changed and vastly improved a full plumbing and heating system and enabled it to work properly for the first time since it was installed.

We love plumbing!

The Results (the new Pressure Pump).

Before – Positive Head Pressure Pump

 old pressure pump

After – Negative Head Pressure Pump

new pressure pump


If you have any questions or comments on this post about our 24-hour service, or any other post on the Dublin Plumber Blog, give us a call on 01 675 0941.

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