Combi boiler advice

The_B_Man

Hi,

I'm getting the attic done.
As part of this, the builder will move the cold water storage tank from the middle of the attic, to the side.
He also said he can replace our gas boiler and 180L cyclinder with a combi boiler.

I have 2 concerns:

1: Will it work with our Aqualisa Aquastream gravity pump shower?
2: Will the pump off the combi boiler be too noisy? I think we can install it in the attic beside the cold water tank, or in the kitchen next to the boiler. If I go to turn on the hot tap after the kids have gone to bed, I don't want to be waking up the whole house!

The builder is local (is from our estate), and said he spoke to the plumber and he said its fine, but the plumber hasn't been to our house. But as I said, they're local and would know the area.

Should we expect a pressure drop in the shower? Or what compromises will we see?

Thanks

Sleeper12

A combi boiler off the cold water tank in the attic is the correct way to install a combi boiler.

Because the hot & cold water from the water tank will be Pumped it will no longer be a gravity fed system. The builder will need to put pressure reduction valves on the hot & cold water going into the Aqualisa Aquastream shower.

discodiva92

Sleeper12 wrote: »

A combi boiler off the cold water tank in the attic is the correct way to install a combi boiler.

Because the hot & cold water from the water tank will be Pumped it will no longer be a gravity fed system. The builder will need to put pressure reduction valves on the hot & cold water going into the Aqualisa Aquastream shower.

Oh my sister just got a combi boiler in a old house and they said you need no tank just the pressure??

Sleeper12

discodiva92 wrote:

Oh my sister just got a combi boiler in a old house and they said you need no tank just the pressure??

Cowboys. Building regulations and bylaws prohibit connection to the mains supply. More importantly, connecting to the mains usually causes problems further down the road. For example a thermostatic shower needs equal pressure from the hot & cold to be able to function correctly. The problem is that the cowboys can quote cheaper prices because they aren't supplying the pump.

The_B_Man

Sleeper12 wrote: »

A combi boiler off the cold water tank in the attic is the correct way to install a combi boiler.

Because the hot & cold water from the water tank will be Pumped it will no longer be a gravity fed system. The builder will need to put pressure reduction valves on the hot & cold water going into the Aqualisa Aquastream shower.

Pressure reduction valves? So I would have thought the more pressure to the shower, the better?

But ye, I know about the regs about kitchen tap and cold water storage tank only being allowed feed off the mains.

The concern I have is of a noisy pump. Is there something I can do to mitigate this? Or is it just "get a more expensive pump"?

BTW, is €2600 a fair price to swap the old boiler and cylinder for the combi? I'd say the builder is adding a few hundred on the top for himself.

Lenar3556

The_B_Man wrote: »

Hi,

I'm getting the attic done.
As part of this, the builder will move the cold water storage tank from the middle of the attic, to the side.
He also said he can replace our gas boiler and 180L cyclinder with a combi boiler.

I have 2 concerns:

1: Will it work with our Aqualisa Aquastream gravity pump shower?
2: Will the pump off the combi boiler be too noisy? I think we can install it in the attic beside the cold water tank, or in the kitchen next to the boiler. If I go to turn on the hot tap after the kids have gone to bed, I don't want to be waking up the whole house!

The builder is local (is from our estate), and said he spoke to the plumber and he said its fine, but the plumber hasn't been to our house. But as I said, they're local and would know the area.

Should we expect a pressure drop in the shower? Or what compromises will we see?

Thanks

You would want to check the spec on any proposed combi boiler that it is going to be able to keep up with the aquastream.

I’m guessing this is arising because it will not be possible to achieve sufficient head height between the tank and toilets/basins and perhaps a shower? being installed as part of this attic conversion?

For the reasons you have already identified, I would be hesitant about going down this road unless it is fully planned. I would probably be more inclined to install a quality twin impeller pump in the hot press to boost the hot and cold supplies to the conversion only.

I’d leave the existing alone if it’s working well and not otherwise in need of upgrade.

Lenar3556

The_B_Man wrote: »

Pressure reduction valves? So I would have thought the more pressure to the shower, the better?

But ye, I know about the regs about kitchen tap and cold water storage tank only being allowed feed off the mains.

The concern I have is of a noisy pump. Is there something I can do to mitigate this? Or is it just "get a more expensive pump"?

BTW, is €2600 a fair price to swap the old boiler and cylinder for the combi? I'd say the builder is adding a few hundred on the top for himself.

Internally pumped power showers have limits when it comes to the incoming pressure they can accept. I think aquastream is about 1 bar. Others manufacturers are less.

Price to change boiler sounds pretty typical if it’s a quality brand - but as above, tread carefully. You would need an undertaking that they are to be responsible for the full delivery of this ‘solution’.

Sleeper12

The_B_Man wrote:

Pressure reduction valves? So I would have thought the more pressure to the shower, the better?

Pumped showers are designed for low pressure systems. If the pressure is too high then you can blow the motor in the Aquastream. A bigger fear of mine is that if the Aquastream wasn't installed correctly at the original installation then the pipes can shoot back into the wall & flood the house. Pressure reducing valves will stop this from happening and keep it within the installation requirements

The_B_Man wrote:

BTW, is €2600 a fair price to swap the old boiler and cylinder for the combi? I'd say the builder is adding a few hundred on the top for himself.

I'm a shower man and not the best to be quoting prices on boilers but I would think its a great price, especially if installing a pump. Not all quotes are alike though. You need a magnaclean installed if you don't have one already & ideally the system will be power flushed too. Not sure if this is included in the price

discodiva92

Sleeper12 wrote: »

Cowboys. Building regulations and bylaws prohibit connection to the mains supply. More importantly, connecting to the mains usually causes problems further down the road. For example a thermostatic shower needs equal pressure from the hot & cold to be able to function correctly. The problem is that the cowboys can quote cheaper prices because they aren't supplying the pump.

I will have to double check but basically they said the pressure in the area was strong enough and sais she didn't need the old water tank in the attic ..they drained that

Lenar3556

discodiva92 wrote: »

I will have to double check but basically they said the pressure in the area was strong enough and sais she didn't need the old water tank in the attic ..they drained that

There are lots of them done like that, and it may work fine, but it’s not something you would recommend.

Incoming mains pressure can vary, both up and down which could considerably impact performance in the future.

There is no longer any stored water, for use in the event of an outage, and there are building regulation compliance issues which any surveyor is likely to identify in the event of a house being sold. Lack of a water storage tank would be a give away.

discodiva92

Lenar3556 wrote: »

There are lots of them done like that, and it may work fine, but it’s not something you would recommend.

Incoming mains pressure can vary, both up and down which could considerably impact performance in the future.

There is no longer any stored water, for use in the event of an outage, and there are building regulation compliance issues which any surveyor is likely to identify in the event of a house being sold. Lack of a water storage tank would be a give away.

Thank you
They recommend combi boiler because existing gas connection.Said the pressure is high enough in the area and also the tank is an old metal one in the attic
It still has to be commissioned.
What questions should she be asking?

Sleeper12

discodiva92 wrote:

Thank you They recommend combi boiler because existing gas connection.Said the pressure is high enough in the area and also the tank is an old metal one in the attic It still has to be commissioned. What questions should she be asking?

I think she should be looking for quotes for RGI guys that will do the job properly.

She should be getting a new plastic tank in the attic, pump for hot and cold, combi boiler, power flush and magnaclean. Anyone suggesting that she doesn't need the above should be avoided.

Does she really need a combi boiler? Would she get away with a new regular boiler, plastic tank, power flush, magnaclean and leave the hot water cylinder?

I had a call from a guy who got the setup you are talking about. He called me in shortly afterwards because his shower had a bad leak. Shower wasn't supposed to be connected to the mains water supply. I couldn't touch the shower with the set up he had. The guy who installed the combi & caused the problem wouldn't come back. He threatened me over the phone & hung up. Homeowner had to engage another plumber to install a very basic old style manual shower. He could never have a modern thermostatic shower in his home because of the uneven pressure. He has another shower that he can't use until he saves enough money to have this replaced with a manual shower.

It's my opinion that you shouldn't engage the services of a plumber that gives you the wrong advice and is willing to leave you with a setup that he knows will most likely cause you heartache further down the road

discodiva92

Sleeper12 wrote: »

I think she should be looking for quotes for RGI guys that will do the job properly.

She should be getting a new plastic tank in the attic, pump for hot and cold, combi boiler, power flush and magnaclean. Anyone suggesting that she doesn't need the above should be avoided.

Does she really need a combi boiler? Would she get away with a new regular boiler, plastic tank, power flush, magnaclean and leave the hot water cylinder?

I had a call from a guy who got the setup you are talking about. He called me in shortly afterwards because his shower had a bad leak. Shower wasn't supposed to be connected to the mains water supply. I couldn't touch the shower with the set up he had. The guy who installed the combi & caused the problem wouldn't come back. He threatened me over the phone & hung up. Homeowner had to engage another plumber to install a very basic old style manual shower. He could never have a modern thermostatic shower in his home because of the uneven pressure. He has another shower that he can't use until he saves enough money to have this replaced with a manual shower.

It's my opinion that you shouldn't engage the services of a plumber that gives you the wrong advice and is willing to leave you with a setup that he knows will most likely cause you heartache further down the road

Thank you for the reply
The company are considered one of the best around the area and so work for Gas networks
I will try get more details if you don't mind me adding more later on?

Sleeper12

I'm not a boiler guy. Some people on here are very knowledgeable about these things. They can advise far better than I can.

Back Home

Sleeper12 wrote: »

I think she should be looking for quotes for RGI guys that will do the job properly.

She should be getting a new plastic tank in the attic, pump for hot and cold, combi boiler, power flush and magnaclean. Anyone suggesting that she doesn't need the above should be avoided.

Does she really need a combi boiler? Would she get away with a new regular boiler, plastic tank, power flush, magnaclean and leave the hot water cylinder?

I had a call from a guy who got the setup you are talking about. He called me in shortly afterwards because his shower had a bad leak. Shower wasn't supposed to be connected to the mains water supply. I couldn't touch the shower with the set up he had. The guy who installed the combi & caused the problem wouldn't come back. He threatened me over the phone & hung up. Homeowner had to engage another plumber to install a very basic old style manual shower. He could never have a modern thermostatic shower in his home because of the uneven pressure. He has another shower that he can't use until he saves enough money to have this replaced with a manual shower.

It's my opinion that you shouldn't engage the services of a plumber that gives you the wrong advice and is willing to leave you with a setup that he knows will most likely cause you heartache further down the road

May I ask are you a plumber? I had a combi fitted to the mains buy a very fussy plumber, no issues in nine years.

The_B_Man

Lenar3556 wrote: »

You would want to check the spec on any proposed combi boiler that it is going to be able to keep up with the aquastream.

I’m guessing this is arising because it will not be possible to achieve sufficient head height between the tank and toilets/basins and perhaps a shower? being installed as part of this attic conversion?

For the reasons you have already identified, I would be hesitant about going down this road unless it is fully planned. I would probably be more inclined to install a quality twin impeller pump in the hot press to boost the hot and cold supplies to the conversion only.

I’d leave the existing alone if it’s working well and not otherwise in need of upgrade.

No, its getting done because we got the house replumbed 3 years ago and the previous plumber left the cyclinder under the stairs, so we want that gone so we can have some understairs storage, or possibly a small toilet.

The boiler itself is in the kitchen and the combi would go into the same spot and use the same pipes. There'll be no bathroom installed in the attic, so its just the one bathroom with toilet, sink, bath and walk-in shower. Possibly a future downstairs toilet (he quoted €3800).

So basically we just want to see if we can use a combi-boiler without it being a downgrade in terms of water pressure (and noise).

Sleeper12

Back Home wrote:

May I ask are you a plumber? I had a combi fitted to the mains buy a very fussy plumber, no issues in nine years.

I'm a plumber but I specialise in showers. He wasn't really that fussy as he installed the combi against the building regulations, Irish water regulations and the local bylaws. If Irish water decide to reduce the pressure in your area then you might have problems. You will then be faced with the expense of paying another plumber to rectify his mistakes. On the other hand you might be lucky & not have any problems. A good plumber won't take the risk. They will install it correctly and you will never need to worry what might happen down the road

Back Home

I appreciate your reply and advice but every plumbing situation is different , my plumber was particular about everything and did inform me of the issues you've described and made allowances for fitting an Aqua box later on if there are any issues but did not want to go to the expense initially. In my situation because I have lots of attic space and theres adequate space next to the boiler for fitting an Aqua box if required. There’s been no issue whatsoever and has been working flawlessly for years. One piece of advice I'd give would be to make sure the pipework is in excelent condition as combies operate on higher pressure and cause cause leaks that are difficult to find.

Back Home

Sleeper12 wrote: »

I'm a plumber but I specialise in showers. He wasn't really that fussy as he installed the combi against the building regulations, Irish water regulations and the local bylaws. If Irish water decide to reduce the pressure in your area then you might have problems. You will then be faced with the expense of paying another plumber to rectify his mistakes. On the other hand you might be lucky & not have any problems. A good plumber won't take the risk. They will install it correctly and you will never need to worry what might happen down the road

I appreciate your reply and advice but every plumbing situation is different , my plumber was particular about everything and did inform me of the issues you've described and made allowances for fitting an Aqua box later on if there are any issues but did not want to go to the expense initially. In my situation because I have lots of attic space and theres adequate space next to the boiler for fitting an Aqua box if required. There’s been no issue whatsoever and has been working flawlessly for years. One piece of advice I'd give would be to make sure the pipework is in excelent condition as combies operate on higher pressure and cause cause leaks that are difficult to find.

Wearb

Not everything. He ignored building regulations which are there to protect the drinking water supply. I know some are done like yours, but it's not the correct way.

Back Home wrote: »

I appreciate your reply and advice but every plumbing situation is different , my plumber was particular about everything and did inform me of the issues you've described and made allowances for fitting an Aqua box later on if there are any issues but did not want to go to the expense initially. In my situation because I have lots of attic space and theres adequate space next to the boiler for fitting an Aqua box if required. There’s been no issue whatsoever and has been working flawlessly for years. One piece of advice I'd give would be to make sure the pipework is in excelent condition as combies operate on higher pressure and cause cause leaks that are difficult to find.

Back Home

Sleeper12 wrote: »

I'm a plumber but I specialise in showers. He wasn't really that fussy as he installed the combi against the building regulations, Irish water regulations and the local bylaws. If Irish water decide to reduce the pressure in your area then you might have problems. You will then be faced with the expense of paying another plumber to rectify his mistakes. On the other hand you might be lucky & not have any problems. A good plumber won't take the risk. They will install it correctly and you will never need to worry what might happen down the road

Would you have a link to the regs, Thanks

Sleeper12

Back Home wrote: »

Would you have a link to the regs, Thanks

From Irish Water site
https://www.boards.ie/vbulletin/attachment.php?attachmentid=482188&d=1559929644


https://www.water.ie/our-customer-commitment/Code-of-Practice-for-Water-Supply.pdf

Back Home

Sleeper12 wrote: »

From Irish Water site
https://www.boards.ie/vbulletin/attachment.php?attachmentid=482188&d=1559929644


https://www.water.ie/our-customer-commitment/Code-of-Practice-for-Water-Supply.pdf

Thanks again for the links, it will guide my next plumbing project.

The_B_Man

I went into a neighbours house to look at his combi boiler. His is in the attic next to cold water storage and has no pump. Is this coz it's in the attic (gravity etc)?
If I'm converting the attic, I wonder is it worth trying to move the boiler up, while the floors are up?
I'm sure they could still use most of the existing piping.

Sleeper12

The_B_Man wrote: »

I went into a neighbours house to look at his combi boiler. His is in the attic next to cold water storage and has no pump. Is this coz it's in the attic (gravity etc)?
If I'm converting the attic, I wonder is it worth trying to move the boiler up, while the floors are up?
I'm sure they could still use most of the existing piping.

Some people put it in the attic to have it up & out of the way. Again I say I don't do boilers but I would think the only disadvantage with this setup is that a gas line would need to be run to the attic. It would need to be in an accessible place & i could see service engineers not wanting to climb over the Christmas tree & twenty suitcases to get to it for the annual service

dathi

Sleeper12 wrote: »

From Irish Water site
https://www.boards.ie/vbulletin/attachment.php?attachmentid=482188&d=1559929644


https://www.water.ie/our-customer-commitment/Code-of-Practice-for-Water-Supply.pdf

the above links deal with Irish waters NEW connection code of practice for anyone wanting to make a NEW connection to Irish water mains the link below is to the building regulations TGDs which show what was required when the house was built and must be complied with when alterations are done.

https://www.gov.ie/en/publication/d1ec3-technical-guidance-document-g-hygiene/

Sleeper12

dathi wrote:

the above links deal with Irish waters NEW connection code of practice for anyone wanting to make a NEW connection to Irish water mains the link below is to the building regulations TGDs which show what was required when the house was built and must be complied with when alterations are done.

I get you. Local bylaws go back to the 60s and 70s and they cover this too. It has always been the case that a cold water tank is required

At the end of the day no one will go to jail for breaking these regulations. It probably won't make problems when selling the property. At the end of the day it's just bad practice.

Sleeper12

Sleeper12 wrote: »

Some people put it in the attic to have it up & out of the way. Again I say I don't do boilers but I would think the only disadvantage with this setup is that a gas line would need to be run to the attic. It would need to be in an accessible place & i could see service engineers not wanting to climb over the Christmas tree & twenty suitcases to get to it for the annual service

All good points the two I would add would be excessive air annoying the boiler as it’s the highest point and the home owner having to climb up to the loft to reset the boiler or to even change the settings.