Bolier Low Pressure: Is the problem with Irish Waters or with my Boiler?

spikyspiegel

Hello,

TLDR: In my recent visit of the boiler service I was told that the issue I have with my boiler (low pressure fault when heating the water) should be resolved with Irish Waters as they are responsible for little pressure in the water pipes and he can't do anything about it.

I had my boiler expansion vessel replaced a month ago, as before it was faulty and the pressure was going too high.

The new expansion vessel was installed externaly, and the old one serves as a dead leg.

The Baseline pressure of the boiler is around 0.8 and when I press boost for heating water it drops to around 0.4 and the boiler stops working. When I boost house heating, the pressure drops too but it's just enough to work, and if I do both heating and water, they will work fine. It's only when I boost water on itself I get 108 error low pressure.

The engineer told me there is nothing he can do about it and when he tries to represurise the system nothing happens because the pressure in pipes in the streets is too low.

He told me that Irish Waters promise to deliver 1.0 bar to every house and that probably I have 1.0 on my tap, but because my boiler is on the first floor it loses 0.2 bar.

He also told be that Irish Waters has been lowering the water pressure for the past months and that more and more people have problems with it and the more people complain then maybe something can be done about it.

He pumped the expansion vessel with his pump to 1.5 bar but said it's only a temporary solution, and not something to do repeteadly.

Boiler Make: Ariston Clas HE with externaly installed expansion vessel.

Has anyone run into similar problems with their boiler or with the low pressure of water in the living area?
Is it normal for the boiler to drop pressure when turned on? Before the instalation of external expansion vessel the pressure would usually go up when turned on.

I'm not sure what to do now as speaking to Irish Waters likely won't solve anything.

spikyspiegel

I have a water tank in the attic.
The landlord says that in the past he used to open the filling loop and leave it open up to 30 minutes to see a rise in the pressure.

spikyspiegel

Apparently, the internal expansion vessel in working condition has ability to counter the pressure drop, as to "limit the negative effect of the pump by providing a ‘neutral’ pressure point on the pipework."

The external expansion vessel doesn't do that trick.

I'm wondering if that's engineer's mistake for installing external expansion vessel. If he missed that because he wasn't aware about how low pressure is in the mains.

I'm wondering if it's better to replace the original internal expansion vessel unit and get rid of the external one. Or install a small water pump or something.

Either way I think that me being asked by engineer to contact Irish Waters is a joke.

Lenar3556

If the incoming mains pressure is insufficient to charge the system, then in most cases an installer would simply use a test pump to add water and fill it to the required pressure.

Varying the expansion vessel pre charge pressure is not the solution, and I can’t imagine it would have helped much.

The issue of low incoming water pressure (if there is one) could be raised with Irish Water certainly. Is there low pressure at your kitchen sink?