Replacing Glow worm spacer saver boiler

Apollo22

I am guessing this is between 20-30 years old.  While my floors are up I can get a fatter gas pipe put in and put in a combi.  Also get rid of a lot pipe work in the loft. No benefit to energy rating.  The only advantage maybe if I rent the place and that’s a toss up.

I did s search but the last thread was 4 years old and non firm conclusion.  Not covered by a heating contract as too old.

grumbler

Glow Warm Space Saver?

And the question is .... ?

I think installing a condensing boiler will benefit the energy rating - if you really need this for renting. My boiler is almost 30 y.o. and I have no plans of replacing it unless it breaks beyond economical repair. Unlike in modern boilers, in old ones there is no almost anything that can break or can't be repaired easily and at low cost.

FreeBear

In the middle of having my boiler replaced - Engineer turned up yesterday, drilled a couple of holes in the wall and hung the boiler, then ***ked off until Monday. Prior to that, I had been busy replumbing the central heating system (22mm pipes throughout, with short lengths of 15mm to the radiators). Also took the opportunity to put in a couple of larger radiators - All of this will allow me to run at a lower flow temperature, and hopefully future-proof me for the day when ASHP is needed.

Going from an old Baxi back boiler to a new combi in conjunction with a programmable thermostat & TRVs on all the radiators is worth a couple of points on the EPC (not that I have one, nor do I really care for one). Also insulating walls as much as I can (already up to ~300mm in the loft), so that will be worth another couple of points.

Gone for a Viessmann 050-W - It has a fairly good reputation from what I can see, and is OpenTherm compatible (gives me the ability to integrate it in to my home automation system).

Apollo22

Sorry I was not clear. I don’t need to replace it. However as the house is been fixed the ceilings are being redone and the downstairs floor, so there is good access.
My option is to put a fatter gas pipe in and keep the old boiler or replace every thing.  I am just wondering if it’s worth doing the whole lot or just doing the gas pipe while I have access.  The old one runs ok, but some of the valves and thermostat needs changing.  I just thought if I decide to rent out the house it’s it better to have a combi?

FreeBear

You can not replace the gas pipe - You'd need to get a Gas Safe engineer to do it for you. Making changes to the CH/DWH plumbing is something that you could do yourself. But if you are not planning on changing the boiler any time soon, it probably isn't worth the effort.

What is the current EPC rating of the property ?

grumbler

Apollo22 said:

I just thought if I decide to rent out the house it’s it better to have a combi?

Why? Combi has both advantages and disadvantages. Condensing is more energy-efficient. That said, I think all new boilers are condensing.

FreeBear said:

You can not replace the gas pipe - You'd need to get a Gas Safe engineer to do it for you.

You can get an engineer to change the gas pipes now and keep the old boiler.

FreeBear

grumbler said:

FreeBear said:

You can not replace the gas pipe - You'd need to get a Gas Safe engineer to do it for you.

You can get an engineer to change the gas pipes now and keep the old boiler.

True, but at what cost ?

In 5 or 10 years, gas boilers may well be banned and everyone has to install heat pumps as an alternative. So unless the OP is planning on swapping the boiler out within the next few years, there isn't really much point (also, if the house is likely sold within a year or three, why bother). But, as I alluded to earlier, it makes sense to modify the plumbing so that it is heat pump ready when the time comes.

Also worth looking at the wiring and adding a few more sockets whilst the ceilings are down & floorboards up.

ThisIsWeird

As said above, Apollo, the MSE way would be to nurse your existing boiler along until it finally goes kaput. Then you make a decision depending on the available options, the cheapest being a new heat-only boiler (like you have, but more efficient).

This will also tend to be the more reliable option.

Combis undoubtedly have their place, but also do a lot more work, so tend to be less reliable over time. 

Future heat sources will also most likely require a water store, so depending on how long you plan to keep this house, I think I'd be inclined to keep the existing hot cylinder in its dedicated space - if you remove it and turn it into something else, you may to redo that at some point!

Apollo22

FreeBear said:

You can not replace the gas pipe - You'd need to get a Gas Safe engineer to do it for you. Making changes to the CH/DWH plumbing is something that you could do yourself. But if you are not planning on changing the boiler any time soon, it probably isn't worth the effort.

What is the current EPC rating of the property ?

I am not doing anything tbh. An engineer will do the gas pipe, if I get it done.

Current EPC rating is E and the boiler and TRV make very little difference.

I suspect I maybe there longer than I could like because living in a flat is not particularly appealing, even though it’s more in Central London. Also I live in my own so having the flexibility of hot water on demand, rather than a tank seemed like a good idea.

Also if the boiler needed replacing it would be easier.

ThisIsWeird

It's not an obvious call to make, I don't think, Apollo. Each type has its pros and cons.

In a smaller flat, I'd almost certainly go 'combi' simply due to the space-saving. With multiple-occupancy, a stored hot water system will almost always be preferred.

The sensible thing to do is - nothing. If the current boiler works, then keep it until it goes kaput. Then you make a decision based on possibly-changed circumstances, and possibly even new technologies.

Since you are doing refurb'ing work at the mo', then it could well make sense to run a larger pipe now that will cope with a combi in future, rather than have the combi option dismissed later on as 'too much upheaval'. If it isn't too much hassle, then I'd probably even employ it as the current boiler's gas pipe right away, so that means you can remove, or cut flush, the existing pipe. No point having two pipes.

Yes, the best thing about a combi is the instant and endless supply of hot water, and only paying for what you use.

BUFF

ThisIsWeird said:

Yes, the best thing about a combi is the instant and endless supply of hot water, and only paying for what you use.

& possibly at higher pressure for a better shower (assuming that the current dhw tank is not unvented).