Heating upgrade questions

golfhead

We are planning to upgrade the heating system and insulation in our house and would be grateful for advice. My knowledge of heating systems is very basic and the plan outlined below is not based on any scientific wisdom but rather from picking up ideas from the internet.

Background

• House is a 20 year old semi-d bungalow which we extended some years ago increasing the square footage from 950 to c.1,300.
• We did not upgrade the oil burner during this extension but we do have it serviced every 24 months or so.
• The attic insulation in the original part of the bungalow is pretty basic
• Most of the radiators in the house are now 20 years old.
• Our heating regime is to use oil for an hour in the morning and again in the evening when we come in from work. We also light a coal fire which we then use to heat the house using a Grant Triple X back boiler which was installed when the house was being built. During this time (from say 7–10 o’clock) we would use a bucket of coal.
• We have never had the system power-flushed so most of the radiators are just hot at the top.
• One bedroom is noticeable colder than the rest of the house

So I would be grateful for some views on the following ideas which we are considering

• Replacing the oil burner completely and install a Magna-clean device at the same time
• Insulating the attic in the original part of the house
• Installing thermostatic radiator valves
• Possibly internally insulating the external walls of the cold bedroom
• Possibly seeing if the heating system in the house can be zoned
• Possibly replacing radiators in the most used rooms in the house

Irish Steve

You should be able to get some grant aid from SEAI,

The boiler will not be as efficient as a modern condensing boiler, but there may be "issues" trying to combine it with a back boiler.

Ideally, all the walls should be insulated, not just the older part, and the roof will benefit from insulation.

If there have not been leaks in the system, the radiators should not be in bad condition as such, thermostatic valves may well help, If the radiators are just hot at the top, that may be they are partially blocked, or the pump may not be doing the job any more, without someone looking at the system, it's hard to know.

Zoning may help, depending on the layout of the house.

If the radiators have been taken off the walls for decorating, it is possible that the only issue is that the system needs balancing.

The whole system needs to be looked at by a specialist, while people here can give advice, the only way to be sure and to get the best value for money will be by letting people quote based on what they see on site.

shane0007

TBH, it will really depend on what you are looking to achieve, what your expectations of a newly overhauled system will be, what your opinions are on the solid fuel side of things & most importantly what your budget is.

Without question, a combined system with solid fuel will have sludge issues & by the sounds of the heat levels of your rads, sludge will be a significant issue.

jack of all

shane0007 wrote: »

Without question, a combined system with solid fuel will have sludge issues & by the sounds of the heat levels of your rads, sludge will be a significant issue.

I don't want to hijack the OP's thread but why would a combined system have sludge issues (due to open vented installation for back boiler?)?

shane0007

Nearly all uncontrollable heat sources overheat & will pitch. They are also nearly all installed with the bulk of the system in negative pressure.
Both these lead re-oxygenation of the heating system water, which in turn oxidises the ferrous metals of the system, leading to black iron oxide & in extreme cases red iron oxide.

I have yet to come across a 20 year old or even a lot younger solid fuel system without substantial amounts of sludge.

jack of all

Thank you for your excellent answer shane0007, I'm only a DIYer but I like to understand how these things work!

whizbang

Replacing the boiler will save you about €20 per year. Payback time about 60 years
TRVs will save you an additional €1.20 per year. Pay back time 100 years
Zoning. €10 per year. Payback time 20 years.
Radiators. €5 per year. Payback time 50 years.
Magnaclean. Payback time 1 lightyear.

Insulation. ( no comment reqd)

shane0007

whizbang wrote: »

Replacing the boiler will save you about €20 per year. Payback time about 60 years
TRVs will save you an additional €1.20 per year. Pay back time 100 years
Zoning. €10 per year. Payback time 20 years.
Radiators. €5 per year. Payback time 50 years.
Magnaclean. Payback time 1 lightyear.

Insulation. ( no comment reqd)

Absolutely love to know where you got those figures from?
A guess, calculated or read as they are way off the mark.

golfhead

Folks

Thanks for replies so far.

We have budgeted up to €7,000 for the upgrade.

We are undertaking the work not because the house is particularly cold but we are aware that we can make it more energy-efficient and that there are grants and tax breaks available to do so. Our expectations would be that our heating system would be used in a more-efficient manner and that we would therefore reduce our annual spend on oil and solid fuel as a result.

We will of course talk to a number of contractors before deciding what specific works will be done but we are just looking to get some general advice on the issues involved.

What possible issue is there trying to combine a combination boiler with the existing back boiler?

Would the Magna-Clean not eliminate the sludge issue and the cold radiator problem?

shane0007

€7k maybe a decent budget, it would really depend on how much the insulation works will cost.
For the grant route & tax break route, go for new Grant Vortex boiler, with time & temperature zone controls. Solid fuel may or may not be an issue depending on what's there at the mo.

A powerflush would be a must with proper inhibitors added, then & only then would magnaclean or similar be effective.

Depending on your system parameters, as discussed on another recent thread, the Firebird heat exchanger might be an option.

whizbang

Keyboard stabbing complete utter random rubbish, a bit like my golf scores.

But there was a point intended. For the current usage, the financial (and even environmental) gain of replacing the oil boiler would be less than zero.

If you bought 7k worth of coal instead of upgrading, you would have effectively have free heat for a long time.

shane0007

whizbang wrote: »

If you bought 7k worth of coal instead of upgrading, you would have effectively have free heat for a long time.

If I bought €7k of diesel for my car, I'd have free driving for a while too but then again, it's wasn't free. I just paid €7k for it.

If a boiler & heating system was 30% more efficient than my old system & I got 5 years heating out of the old system for €7k, my new system would give me 6.5 years for the same buck.

:-)

golfhead

Do TRV valves and zoning do the same job in different ways?

If so, I'm guessing the TRV option would be a lot cheaper.

shane0007

golfhead wrote: »

Do TRV valves and zoning do the same job in different ways?

If so, I'm guessing the TRV option would be a lot cheaper.

No. Zoning is far superior as it allows full time & temperature control with what is known as boiler interlock. This means when the zone reaches it's desired temperature it will electrically turn off the boiler.
TRV'S only close down one radiator but do not turn off the boiler, so they encourage boiler short cycling which is not good.
You should also never have a trv in the same room as the room thermostat. They will conflict.

Outkast_IRE

golfhead wrote: »

Do TRV valves and zoning do the same job in different ways?

If so, I'm guessing the TRV option would be a lot cheaper.

No its not the same, let me give you an everyday example.

A 2 storey house has an upstairs zone and downstairs zone, and trvs on each rad.
This allows the user to set upstairs heating only to come on just before bed time if they want, and downstairs heating to come on before they get up. The TRVS will then control the individual rads in this zone based on air temp.

This is probably the best level of control an average house can achieve cost effectively.

If you don't zone the system, lets say you want the heating on for an hour before bed, you will be allowing every room to heat and relying on the TRVs to control individual rads, this will obviously lead to you heating some areas that aren't necessary.


Zoning combined with TRVs is always the best way to do a standard system, I always recommend people think about their zone before installing, and plan the zones to make sense.

You would often hear people say not to fit a TRV in the same room as the Themostat as they will conflict one another