Which Boiler/System To Go For. Advice and Help Needed

[posativek]

High there

I have moved in to a 3 bed house. Standard Wimpy crap from the mid 90's. Hollow dry walls, and an old fashioned system.

* 8 Radiators
* Two Tanks ( I think) pitch on the roof is so low I dont go up very often.
* Cylinder in cupboard
* Potterton Prima F (conventional) biler chugging away quite happily in the kitchen.

Now I would have been happy with this set up, as it works. However after installing a new bathroom, and those new fangled barrel taps (quarter turn jobs) I now have a useless shower. It wasnt great before hand to be honest 'bearable' would be the word.

So I decided to put in a pump. The only issue is, I dont want the noise, I dont want the yards of plumbing needed and the possible reliability issues once installed.
I was also getting confused about why I could have it under the bath and why it had to be in the airing cupboard. Basically it wasnt going to be as easy and cheap as I thought.

The next option came to Pressurised tank such as the Megaflo.
This seemed like a great idea becuase I would have no need for the loft tanks (although they dont get in the way and cause any problems), and I would have mains pressure to all taps allowing me to have a decent shower again. (My shower runs off a mixer from the taps)

Then I started to learn about the on going costs (annual inspections) and how much it would be to install. It will probably cost about £500 more than a pump. This has started to become annoying becuase i will essentially be paying yearly for pressure in taps I dont need really. I only need better pressure in the shower.

So I am stuck between the two choices. I havent as yet found out how much it is exactly to fit the Cylinder nor the ongoing service costs.

Then I started thinking. If I get a Combi boiler. That way I can get the mains pressure to my shower without the need for a pump, a more economical boiler/heating system and get rid of the tanks and the cylinder.

Then there are the downsides. Combi boilers are notoriously fussy and unreliable. If they break down, you will have no hot water. They might not be able to supply enough hot water for the shower pending on the pressure. I might not have enough pressure to run a combi (obviously I will have to find that out)


There is also the other choice of getting a system boiler, which I assume works with the Pressurised cylinder (megaflo) or it works like my Potterton. Im not 100% sure what they do although they sound like a good alternative.

Basically im learning al lot and a decision like this should be taken with a better understanding of the choices, hence why I am here asking fo some advice.
I want to get the right system/solution becuase its going to be the one that lasts another 15 years at some expense.

Im leaning towards maybe A combi with stored water. That way I can get the economical product with some hot water back up. I am still concerned about the lack of available hot water to more than one outlet (tap). I would also want one that is bullet proof and doesnt constantly break down (like the one I had whilst I was a student)

So maybe the system boiler is better.

?????? Please help. Dont forget this all started because of a bloody shower lol.

 

[petertheplumber12]

A system boiler works the same as the open vented you have got except it has an expansion vessel and that removes the need for a feed and expansion tank and also the pump is in the boiler, which means it has a very efficient means of removing air from the system, no rad bleeding means no sludge. i am about to go on a one day course with intergas to have a better look at there boilers, I know they do a 30kw it is called intergas combi compact HRE 30SB and comes with the option of an external expansion vessel which i prefer for maintenance purposes. They are very reliable with very few moving parts and their combi version doesn't use a secondary heat exchanger and divertor valve which means less to go wrong, they are Danish manufacture and have been going for 10 years I believe, might be longer, produced about 1.5 million boilers. I also plan to put one in my house. next year.

 

[Dan Robinson]

I know they do a 30kw it is called intergas combi compact HRE 30SB

The SB is a Combi .

The SB can also be run open vented though, as can the Combi's.


Not read the full OP, but a combi can be used to run the shower whilst the cylinder and heating are heated traditionally. Best of both worlds.

 

[posativek]

A system boiler works the same as the open vented you have got except it has an expansion vessel and that removes the need for a feed and expansion tank and also the pump is in the boiler, which means it has a very efficient means of removing air from the system, no rad bleeding means no sludge. i am about to go on a one day course with intergas to have a better look at there boilers, I know they do a 30kw it is called intergas combi compact HRE 30SB and comes with the option of an external expansion vessel which i prefer for maintenance purposes. They are very reliable with very few moving parts and their combi version doesn't use a secondary heat exchanger and divertor valve which means less to go wrong, they are Danish manufacture and have been going for 10 years I believe, might be longer, produced about 1.5 million boilers. I also plan to put one in my house. next year.

Thanks a lot for your reply.

Im a little confused about were the combi bit comes in? I didnt think system boilers were combi boilers?

So Im not really sure what your saying. Are you suggesting a system boiler or a combi boiler or can they be the same thing?

When you say the system boiler having an in built expansion tank removes the need for a feed and expansion tank, what do you mean by feed? I also dont seem to have an external expansion tank.

I will look into the boiler you suggest.

 

[posativek]

I know they do a 30kw it is called intergas combi compact HRE 30SB

The SB is a Combi .

The SB can also be run open vented though, as can the Combi's.


Not read the full OP, but a combi can be used to run the shower whilst the cylinder and heating are heated traditionally. Best of both worlds.

High Thanks for your reply.

I would be interested in a combi that does the best of both worlds. However combi boilers are trouble.

Im going to look into the boiler.

 

[Dan Robinson]

Combi boilers are no trouble whatsoever- they are just a boiler that does two things.

You have a boiler that does one thing and a cupboard for the hot water (doing the other)

I am suggesting the shower is plumbed through the combi, and maybe a sink. The existing cylinder and controls are then heated the same way they are now.

Peter is slightly confusing the issue i think by using the wrong names.

Intergas/Atmos boilers do however rock.




*edit.

Just noticed from your quote that my auto correct hasn't helped either.

It should read....

The SB isn't a combi.

My apologies.

 

[posativek]

A system boiler works the same as the open vented you have got except it has an expansion vessel and that removes the need for a feed and expansion tank and also the pump is in the boiler, which means it has a very efficient means of removing air from the system, no rad bleeding means no sludge. i am about to go on a one day course with intergas to have a better look at there boilers, I know they do a 30kw it is called intergas combi compact HRE 30SB and comes with the option of an external expansion vessel which i prefer for maintenance purposes. They are very reliable with very few moving parts and their combi version doesn't use a secondary heat exchanger and divertor valve which means less to go wrong, they are Danish manufacture and have been going for 10 years I believe, might be longer, produced about 1.5 million boilers. I also plan to put one in my house. next year.

High peter,

looked into the unit. Seems like a good company. So what your saying is, I should get a combi.
If i get a combi, then I dont need the tanks, cylinders, etc. I can just have the boiler. That sounds good but if it goes down, then there is no hot water.
Also with a combi, if you want to use say the washing machine, wont that effect someones shower? Wont you also lose pressure if two taps are on?

I would prefer a system that isnt so temperamental or am I missing a trick here?

OR am i still a bit confused.

Let me describe my ideal system.

Something that gives good pressure to the shower, something that doesnt lose pressure if others want to ise something, ir temperature. Something economical and something that wont leave me stranded without any hot water.

A lot of those requirements dont seem to match up to well to combi boilers. Am I wrong?

 

[Dan Robinson]

My proposal covers all your bases.

As for taps running cold....thermostatic showers and flow restrictors on taps should cover that problem if indeed it truly exists.

Like a lot of perceived problems, once you drill down in to the practicalities, like controlling your heating from an iPhone....most people are just succumbing to pre- conceived ideas.

 

[posativek]

My proposal covers all your bases.

As for taps running cold....thermostatic showers and flow restrictors on taps should cover that problem if indeed it truly exists.

Like a lot of perceived problems, once you drill down in to the practicalities, like controlling your heating from an iPhone....most people are just succumbing to pre- conceived ideas.

Thanks for your reply Dan.

I wish I knew what it was you were suggesting??? Im obviously too green at this stuff. Ive been researching for 6 hours but im really getting stuck on boilers. Ive just about worked out how the piping in my house is supposed to work.

Your gonna laugh but it seems to me like you are suggesting I get two boilers? I know thats not what you are suggesting though.

If you have the patience please go over it again, but maybe explain it in a way that an idiot would understand (although im sure you already have)

 

[Dan Robinson]

OK.

Fit basins and sinks with 4 litre per min flow restrictors.

Shower is hopefully thermostatic already.

Now... the proposal....

Take out faithful old Primary.

Fit HRE 18/24 combi compact.

Plumb the shower and maybe a sink or basin to the boiler's water side.

High pressure unlimited shower - DONE.


Wire existing wiring for heating and hot water into the boiler.

Fast bath fills with immersion back up for hot water - DONE.


Removal of small header tank is optional.

Upgrading of heating controls highly recommended.

At least a programmable room thermstat like the CM927 from Honeywell.

Weather sensor can be attached to boiler too for self adjusting heating.


Job done.


Simples

 

[posativek]

My proposal covers all your bases.

As for taps running cold....thermostatic showers and flow restrictors on taps should cover that problem if indeed it truly exists.

Like a lot of perceived problems, once you drill down in to the practicalities, like controlling your heating from an iPhone....most people are just succumbing to pre- conceived ideas.

I wil explain what i think your saying.

I get a combi boiler to power the shower and a basin.
I also get it to heat water in my cylinder.

How does it split between the two? Will it heat water in the cylinder by a feed from the loft tank?
Then i use the water from the loft tank (hot and cold) to supply the toilets, downstairs hot water.

So in all, I get the pressure from the combi, and the unlimited hot water shower etc but I also get most of my other hot taps feeds etc from the tank, so if people want to use other appliances taps etc they can.

Am i getting there? (painfully)

 

[Dan Robinson]

Pretty much yes.

The boiler will switch modes when the shower is on and ignore heating and the cylinder for the duration.

In practice you would never notice this.

Limiting the flow to sink and basins will save you water too.

 

[posativek]

OK.

Fit basins and sinks with 4 litre per min flow restrictors.

Shower is hopefully thermostatic already.

Now... the proposal....

Take out faithful old Primary.

Fit HRE 18/24 combi compact.

Plumb the shower and maybe a sink or basin to the boiler's water side.

High pressure unlimited shower - DONE.


Wire existing wiring for heating and hot water into the boiler.

Fast bath fills with immersion back up for hot water - DONE.


Removal of small header tank is optional.

Upgrading of heating controls highly recommended.

At least a programmable room thermstat like the CM927 from Honeywell.

Weather sensor can be attached to boiler too for self adjusting heating.


Job done.


Simples

Ok im getting there.

My shower is on a mixer from the taps in the bath. does that complicate or simplify this process. Im guessing simplify?

Why do you want flow restrictors?

So your saying the combi will run all the taps etc or just the bath and sink?

This whole thing is obviously more complicated than i can do on a forum. I will need someone to come round and explain, or for me to go to a merchant and sit down.

Everytime I understand what your saying, you mention something else that confuses me.(obviously not your fault)

As far as I can gather, you get mains flow into the shower and sink running directly through the combi. You then get the combi to pass hot water through the cylinder to indirectly heat the water there which then combined with the cold in the loft tank will feed the other parts of the house. So to maximise pressure and heat for the shower/bath.

Essentially the ombiu is heating the water for the shower/bath/sink/cylinder and central heating. Everything else comes off the tank in the loft .

 

[posativek]

Pretty much yes.

The boiler will switch modes when the shower is on and ignore heating and the cylinder for the duration.

In practice you would never notice this.

Limiting the flow to sink and basins will save you water too.

Ok its making sense.

So you can get the combi to switch modes.

Limiting the flow does make sense yes, and you would only do it to the taps effected by the combi directly, ok makes sense.


OK so I think I get it now. I can also keep an immersion heater on the boiler in case the boiler breaks down.

So like you say, I get the best of both worlds.

Sounds like a god idea.

 

[Dan Robinson]

A bath shower mixer complicates things as my idea relies on the shower being separate.

Other than that, you had the jist.... now you're moving away again.

The flow restrictors are there purely to save water consumption and minimise the risk of a surprise when under the shower.

The combi is JUST doing the shower (not bath) and a select one or two sinks and basins (maybe).


Again, this won't work unless you have a separate shower valve and bath tap.