Combi boiler experience in Dublin?

When i was getting the bathroom done up i wanted a rain shower and was told i needed a pump to get the needed pressure out of the rain head. Any hot tap in use the pump kicks in to boost the pressure. Having the pump running the sink in the kitchen was splashing water everywhere but i had stop cocks fitted on the lines and closed slightly reduced pressure enough for no splashing.

That was the only reason i needed a pump was the very large shower head to get the flow out my immersion with very large tank.

I have a combi boiler and it was the best upgrade I have done to the house. I use option 1, tank in the attic to a pump then to boiler. Get the biggest boiler you can, i went with the 35kw boiler just to get the best hot water flow rate, the rainfall shower is incredibl. I also moved the boiler to the attic and now the hot press is converted to a linen closet.

Small combi for apartment and large combi for house. Having said that most apartments don't have gas.

There are older threads on this very subject. You will find direct quotes from the current building regulations and older bylaws.

Building regulations are a fairly recent thing in Ireland but we have had building bylaws going back 50 years or more. Building bylaws in Dublin were that every house should have a cold water tank capable of storing 24 hours worth of water. The mains water was solely for drinking water at the kitchen tap and filling the cold water tank in the attic. No combi boilers, electric showers washing machine etc are allowed from the mains supply.

No one is going to jail for breaking these regulations but they are there for a reason. In the UK where combi boilers are a big thing many homes do not have a water tank. Hot or cold. On a Triton training course many years ago I was talking to the instructor about the Triton T90. It's the biggest selling pumped electric shower. It's such a big seller that many people call their electric shower "a Triton" or "a T90" even if they actually have a mira, in the same way that people take out "the hoover" even though it's not a hoover brand. It's a vacuum cleaner and not a hoover. Anyway the reason I mention it now was because no one else on the course had heard of a T90 shower. They all installed mains fed showers and had never heard of a tank fed /gravity electric shower. Their mains pressure is so strong that most homes have to install a pressure reduction valve. Some parts of the UK have more than 10 bar of pressure. In Dublin we are lucky to get one bar of pressure. It's for this reason that our bylaws & building regulations say what they say. In Dublin if you use a mains fed shower you will get scalded if someone uses the cold water at the kitchen tap. In the UK you can run every tap in the house & it still won't effect the temperature of the water in the mains fed shower.

Apart from the regulations it is very bad practice to connect a combi to the mains in Ireland. The reason is that the performance will not be 100%. Even if the combi works perfectly at first Irish water could reduce the water pressure a few percent & the combi won't function properly. You have no comeback with Irish water because the combi is installed against the regulations.

I have a bee in my bonnet about combi boilers installed connected with the mains because I get calls from people thinking that their shower is broken when it's the fact that the combi is on the mains. I had a lady call me. She owns a lives in an apartment. She paid someone to install a combi. He contacted it to the mains. So the hot is 1 bar of pressure and the cold is only a quarter bar of pressure. She could not adjust the temperature at the shower. If she turns the dial a fraction the water will be scalding. Plumber blamed Irish water & and told her she had to adjust the temperature at the combi. So she is supposed to get out of the shower walk into a different room to adjust the temperature and then back into the shower.

Combi boiler should be fed from a tank and pumped. Personally I would be looking at moving towards a heat pump. The average lifespan of combi is 10 years. Eventually you won't be able to buy gas or oil boilers. From, I think, next year it will be illegal to install a gas or oil boiler in a new build. When you eventually go for a heat pump you will need to install the hot water cylinder again

You can install a Triton Noval SR shower imwhich will supply up to 14LPM, it has its own integral pump and requires hor and cold feed via your cold water storage tank and HW cylinder (existing).

A 25kw co.bi will give 10.5LPM at 40C from cold water at 6C, winter & 14.3LPM in summer from cold water if at 15C.

Yes but it was the most sensible option as we went with combi from the beginning.

Not having an attic tank for storage might have been an issue in the past if the water went off but hardly applies these days.

How do the regs apply to outside taps?

Not being smart here i know the regs, just struggle with the good reason bit, surely they are archaic in today's world, with utility rooms and second sinks and outside taps.

In my mother's 70s built house there wasn't any feed for a washing machine/dishwasher from the attic tank, so when installed the feed was branched off the mains at the sink rather than piping all the way up to the attic. Surely this is the norm with older houses?

Is your own washing machine/dishwasher fed from the tank?

Ah that makes perfect sense, got it now.