Which combination storage boiler should i go for?

[GaytonTonner]

Hi thanks for all your responses:

I am fairly certain i do not want a hot air system and happy to go with radiators for a wet system

Why?

 

[GaytonTonner]

I don't like hot air either

Why?

 

[GaytonTonner]

I am still unclear what to go for.

There are three large housing developments under construction near where I live. None of the three or four bed houses, some with two bathrooms, have combi boilers installed. They all have system boilers and Range Tribune type cylinders.

Which means nothing. It could be the decision of some young kid in the office or a deal they have with suppliers.

 

[GaytonTonner]

I still do not understand one point

there is mention that a house of this size should not have a combi - this is fair enough and never suggested

Those who suggest that tend not to have knowledge or experience of high flow combis.

i get the impression the storage combination boilers do not get fitted much and amybe there is not a push towards them. my simple mind cannot see why they would not be a good choice in my situation

Many plumbers do not like combis as it puts them out of much work. You appear to have sussed out they can deliver the DHW, which they can.

A comi heating a Multicalor air handling unit is the way for you,.

 

[totallymedicine]

I still do not understand one point

there is mention that a house of this size should not have a combi - this is fair enough and never suggested

Those who suggest that tend not to have knowledge or experience of high flow combis.

i get the impression the storage combination boilers do not get fitted much and amybe there is not a push towards them. my simple mind cannot see why they would not be a good choice in my situation

Many plumbers do not like combis as it puts them out of much work. You appear to have sussed out they can deliver the DHW, which they can.

A comi heating a Multicalor air handling unit is the way for you,.

You clearly are 'for' the air heating:

1) is this not more expensive to run?
2) does it not make the air feel dry?
3) will i not then have 2 'devices' so to speak to have to look after and maintain - at least with a storage combi does this not i kill 2 birds with one stone (especially if fitting radiators is not a concern to me!)

at present teh johson and starley i have only heated some rooms downstairs well and upstairs it was ok for teh rooms closer to teh boiler - how i can be sure the newer machines with distribute air effectively?

you opinion would be most appreciated

 

[bengasman]

I'd suggest you spend more time of finding a good installer, than on trying to work out what is best based on the opinion of people who have not actually been on site.

For the prelimenairies, you may find the advice from RGI's more reliable than those who do not earn their living in installing/repairing central heating.
D Hailsham and G Tonner are definitely not RGI's.

 

[totallymedicine]

I'd suggest you spend more time of finding a good installer, than on trying to work out what is best based on the opinion of people who have not actually been on site.

For the prelimenairies, you may find the advice from RGI's more reliable than those who do not earn their living in installing/repairing central heating.
D Hailsham and G Tonner are definitely not RGI's.

well if i knew a good installer i would not be on this forum now. I guess a general consensus is a good place to start

in terms of the site - its a pretty standard sized house and feel i have given sufficient information to gain reasonable guidance for now but appreciate your point to some degree

 

[bengasman]

The problem is that you can't really say anything sensible until you've seen and checked everything.

For example: A big combi will happily do two bathrooms, though a megaflow will outperform it.
IF BOTH flow AND pressure are sufficient; if they are not, it won't work.

At the end of the day, the quality of the installer is usually the deciding factor, not the brand, type, or size of the equipment.

I have recently done a job on a 3 year old boiler which was flagship of what by many is considered one of the best brands. Nevertheless, the owner was ready to give up, and asked me to quote for a new one. Must have been best part of £1500 for the kit alone, not counting the 6 foot tall Megaflo.

Spend your time of finding an installer by asking all friends, colleagues, neighbours, church, sports club members etc for recommendations.

 

[GaytonTonner]

You clearly are 'for' the air heating:

1) is this not more expensive to run?

Air heating using a combi is cheaper to run.

2) does it not make the air feel dry?

No, as fresh outside air can be introduced in the flow. A humidifier can be installed in the ducting if you want. They are small and simple enough being spinners. I have mentioned these in a previous post on this thread.

3) will i not then have 2 'devices' so to speak to have to look after and maintain - at least with a storage combi does this not i kill 2 birds with one stone (especially if fitting radiators is not a concern to me!)

The Multicalor is a air handling unit. It only has a copper coil heat exchanger and a fan. There is no burner and complex controls, just a stat to activate the fan when the copper coil is up to temperature. It is service free with only a user filter clean. An electrostatic air filter can be in the ductwork before the unit. If the CH requirements are less than 8kW (check your requiremenmts - what is the existing unit in kW or BUT.hr?) then a J&S Aquair unit can be used. This is a smaller unit than the Multicalor.

The combi heats the copper coil. That is all it does. It also heat the DHw instantly. The Multicalor is like a large Myson. The fan only comes in when heat is ion the unit. There is not control wiring between the combi and the Multicalor. The combi install is standard with a normal stat/programmer. It is simple.

at present teh johson and starley i have only heated some rooms downstairs well and upstairs it was ok for teh rooms closer to teh boiler - how i can be sure the newer machines with distribute air effectively?

It has a three speed fan. The lower speed is usually fine for a normal house. If you want a hurricane coming through it can give you that. The Multicalor is maximum of 20kW, which is big enough for large houses. Even the smallest combis can easily deliver 20kW of heat to heat the Multicalor.

you opinion would be most appreciated

I am doing one right now in an open plan 1960s refurb. It looks like an house in the Avengers - very 60s and superb. The owner wants most original features kept. The owner had builders and plumbers around who said rip out the air system, which was through smart floor registers, and fit rads and an unvented cylinder. The house would have looked crap with rads.

I persuaded the owner to stick with the air system and remove the old cold tank fed, space taking, 1966 Lennox gas burner DHW cylinder, which was still working. The existing warm air unit was a Dutch Blink (J&S rebadge them). It was fine and only 10 years old. The original 1960s unit had lated 36 years.

He wanted high pressure showers and the open flued Blink removed as he didn't like open flues. The solution was a decent DHW flow ATAG combi feeding only a Multicalor air handling unit. A blending valve was put on the ATAGs return to keep the return at 55C. The combi uses the return temp to maintain a delta T, so this valve ensures a high flow and efficient condensing (J&S warm air units burner are not condensing). Tweaking may get to 53 or 52C. 52C in this weather worked fine. The Multicalor fitted directly onto the old units plenum, being slightly shorter as well. The house is flat roofed and the old Lennox flue to outside is now used as an air inlet to the system drawing in a small volume of fresh air. An electrostatic air filter is fitted. A summer switch is fitted to operate the fan only in summer to circulate air.

There is only one flue, the combis, and all room sealed. No need for warm air GasSafe servicemen. The Multicalor does not need GasSafe fitters to fit as anyone can fit it. Only one service per year, the combi.

It works brilliantly. The Multicalor is quiet as well. The owner is delighted and cannot understand why people do not like the systems. All visitors remark about the nice comfy temperatures in this very cold weather. The air temperature is nice and even all around with no cold spots. Rads with his extensive beach flooring and ceilings would have looked just crap. When the room stat cuts in it knocks out the combi, which starves the Multicalor of heat which switches off the fan when cold. When calling for heat the combi comes in heating the coil quickly and off the fan goes again. Simple and easy. The combi gives high pressure showers, saving space.

Getting plumbers to look at heating can be disastrous. They do not understand the full range of heating only understanding rads system because they only understand water in pipes. The worst heating system you can fit in is a rad system.

 

[GaytonTonner]

I'd suggest you spend more time of finding a good installer, than on trying to work out what is best based on the opinion of people who have not actually been on site.

Good advice, but not plumbers. Get men who understand forced air and heating all around and what is available on the market, not what the local merchant gives good discount on.

For the prelimenairies, you may find the advice from RGI's more reliable than those who do not earn their living in installing/repairing central heating.
D Hailsham and G Tonner are definitely not RGI's.

It is clear you had never heard of a Multicalor and heating via a air handling unit and high flow combi. It is best to get advice from men who design and specify heating systems, not the fitters. Fitters will invariably say, "rip it all out guv, you can't beat a system boiler and unvented cylinder", in my best Cockney accent.

 

[GaytonTonner]

in terms of the site - its a pretty standard sized house and feel i have given sufficient information to gain reasonable guidance for now but appreciate your point to some degree

What size is the existing warm air unit in kW or BTU/hr?

 

[GaytonTonner]

The problem is that you can't really say anything sensible until you've seen and checked everything.

For example: A big combi will happily do two bathrooms, though a megaflow will outperform it.
IF BOTH flow AND pressure are sufficient; if they are not, it won't work.

Pressure and flow applies to all mains pressure systems, Megaflows are nor exempt.

This is the sort of misinformation that is about. Both will do two bathrooms. One will runs out of hot water, the Megaflow, the other will not, the instant combi. I have given figures for DHW delivery in a previous post. Please read the figures.

At the end of the day, the quality of the installer is usually the deciding factor, not the brand, type, or size of the equipment.

The best installer in the world installing a poor rad system over a good forced air will always be poor.

Spend your time of finding an installer by asking all friends, colleagues, neighbours, church, sports club members etc for recommendations.

I would advise getting a man who specifies and designs, not a fitter.

 

[totallymedicine]

in terms of the site - its a pretty standard sized house and feel i have given sufficient information to gain reasonable guidance for now but appreciate your point to some degree

What size is the existing warm air unit in kW or BTU/hr?

The unit which no longer works is a j54-64 j&S

the documentation states the following:

15.8-18.8kw (57mj/h, 54,000btu,/h to 67.5mj/h, 64,000but/h

 

[bengasman]

The problem is that you can't really say anything sensible until you've seen and checked everything.

For example: A big combi will happily do two bathrooms, though a megaflow will outperform it.
IF BOTH flow AND pressure are sufficient; if they are not, it won't work.

Pressure and flow applies to all mains pressure systems, Megaflows are nor exempt.

This is the sort of misinformation that is about. Both will do two bathrooms. One will runs out of hot water, the Megaflow, the other will not, the instant combi.

This just demonstrates how useless advice is that comes from somebody who does not work in the trade.

1. He clearly did not get that my statement about pressure and flow related to both a combi and a Megaflo.

2. He is clearly not aware that a cylinder should be sized to meet the expected demand first of all. If the demand was such that the cylinder runs out, the dhw production can be increased, and set at maximum, the hot water will only run out at commercial use.

3. He failed to add the only bit of information that could is of some use:
A Megaflo is significantly more expensive to fit, and slightly more expensive in use/maintenance.

4. His advice to get someone that "also designs" is rather pointless too. Every installer/fitter is capable of designing a system. "Specialist" designers who don't actually install, tend to design things that look good on paper, but are troublesome or ineffective in real life. You may see the similarity with the advice of G T; there is some logic in it, but he misses quite a few essential points.

 

[Tibbot]

in my best Cockney accent.

Water Systems/Drivel/B Burner/G Bramwell etc.. You're about as Manc as I am, though at least I've been there.