D
DarrenThomas
TL;DR version
Getting new combi to replace vented conventional system
Q 1) thoughts and opinions of weather compensating programmers?
Q 2) Most of my CH pipe is 15mm will a chunk of this need to be replaced with 22mm?
Q 3) Condensing boilers need a return of 55c or under to be most efficient. Is my understanding correct?
Q 4) Do you guys take cards? We are paying with a 0% card so anyone who couldn't wouldn;t get a shot at the job. Does it hinder you on bigger jobs if you don't take them?
Q 5 ) What should the DHW temp be set to on the boiler? Can you run at 48 ish and mix with less cold or should you run it nearer 60?
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Long version.
I've finally decided that it is time to replace the existing Potterton Suprima 60 in my 3 bed semi along with most of the rads with it, 2 have already been swapped out during refurbs of the rooms. All others are very old as far as I can see, with at least 2 coats of gloss on all (they were glossed salmon pink when we moved in 3 years ago and we HAD to do something), and no fins on any of them.
The boiler lives in the kitchen and is supplied with a 15mm gas feed which is buried in the wall (concrete floors). From this run 2 22m pipes which go into the airing cupboard in the room above which then feed the cylinder and heating loops. The cylinder is IIRC a 114l unit, with a 50G cold tank in the loft directly above.
Sadly I'm at work for the next 7 days so I shan't have a chance for a man with a plan to come in and talk to me until Wednesday. In the meantime I'm dreaming up all manner of questions.
I'm heading toward a Vaillant boiler, the 4 gas men I've spoken to about various bits in the last 18 months have all harped on about Vaillant so I figure a consensus is always a good starting point.
So my questions
1) I have been looking at a weather compensating set of wireless controls, the price delta between those and the standard wireless controls is only £50 so if they only save me 5% (instead of the quoted 20%) then that's still going to pay itself off. How do you find them? I've been searching around and it seems they are standard in a few European countries. My dad had the Vaillant 392f wireless controls fitted last Christmas despite being told that they were "quite complicated" and has had no issues at all using them.
2) The current 22mm pipes from the boiler go up into the airing cupboard where they go into two valves and the pump. One valve feeds the cylinder and the other the rads. However it's somewhere close to there that the 22mm pipe ends. All the tails are 15mm, and all the pipework on the landing which is next to the cupboard is also all 15mm. This pipework then feeds the front 2 bedrooms as well as the downstairs hall rad and hopefully a new rad to be put in the living room which currently has no heat in it. The entire downstairs of the house is heated by one 700x1100 (ish) double panel no fins rad in the dining room next to the huge patio doors, and one 600x1600 single no fins in the hall!
Am I going to need 22mm run to replace that 15mm?
It shouldn't be too much of an issue to do as the floor on the landing and back bedroom (above boiler and also the room with the cupboard) is all easy to get up. It's just that the 15mm feed that goes to the hall rad downstairs goes under the office carpet which was only put down a few weeks ago.
3) Am I correct in understanding that condensing boilers are most efficient when the return is less than 55C? The gumpf from some of the WC programmers suggests that the savings they claim are based around keeping the boiler at it's most efficient for longer in turn meaning rads will be warm but not hot but maintaining a more even temp.
4) Payment. The only way we can do this is to put it on to a 0% card. I asked the bank for the money and was told that they would happily give it to me after they did a revaluation on the house (£200), paid a product fee (£300) and then paid the 5.5% interest rate. Hardly worth it when compared to the card that we can pay off only only have the 2.8% balance transfer charge to pay on top.
The problem is that not many guys take cards, larger groups do like Smith & Byford but the guy who did one of my rads and some bits for my brother, who is a nice guy and works well doesn't take it. He'd probably be cheaper and let me help out with removing the old kit and nailing the new rads up too but we have no other way of paying.
Do you plumbers find that causes you problems or have you got ways of taking cards even if you typically only take transfers/cash/cheque?
5) I think that's it for now. I know the guys that come to quote will no doubt answer them all, but I like to go into these things with a little idea of what kind of things are good or bad answers.
Thanks 🙂
EDIT: one more thing but it should probably be in the plumbing forum. With my bathroom refurb we fitted a Trevi Boost which suited our circumstances. I read that Trevi do a kit to convert to a Therm but can't seem to find it. Any ideas?
Getting new combi to replace vented conventional system
Q 1) thoughts and opinions of weather compensating programmers?
Q 2) Most of my CH pipe is 15mm will a chunk of this need to be replaced with 22mm?
Q 3) Condensing boilers need a return of 55c or under to be most efficient. Is my understanding correct?
Q 4) Do you guys take cards? We are paying with a 0% card so anyone who couldn't wouldn;t get a shot at the job. Does it hinder you on bigger jobs if you don't take them?
Q 5 ) What should the DHW temp be set to on the boiler? Can you run at 48 ish and mix with less cold or should you run it nearer 60?
----------------------------------------------------------
Long version.
I've finally decided that it is time to replace the existing Potterton Suprima 60 in my 3 bed semi along with most of the rads with it, 2 have already been swapped out during refurbs of the rooms. All others are very old as far as I can see, with at least 2 coats of gloss on all (they were glossed salmon pink when we moved in 3 years ago and we HAD to do something), and no fins on any of them.
The boiler lives in the kitchen and is supplied with a 15mm gas feed which is buried in the wall (concrete floors). From this run 2 22m pipes which go into the airing cupboard in the room above which then feed the cylinder and heating loops. The cylinder is IIRC a 114l unit, with a 50G cold tank in the loft directly above.
Sadly I'm at work for the next 7 days so I shan't have a chance for a man with a plan to come in and talk to me until Wednesday. In the meantime I'm dreaming up all manner of questions.
I'm heading toward a Vaillant boiler, the 4 gas men I've spoken to about various bits in the last 18 months have all harped on about Vaillant so I figure a consensus is always a good starting point.
So my questions
1) I have been looking at a weather compensating set of wireless controls, the price delta between those and the standard wireless controls is only £50 so if they only save me 5% (instead of the quoted 20%) then that's still going to pay itself off. How do you find them? I've been searching around and it seems they are standard in a few European countries. My dad had the Vaillant 392f wireless controls fitted last Christmas despite being told that they were "quite complicated" and has had no issues at all using them.
2) The current 22mm pipes from the boiler go up into the airing cupboard where they go into two valves and the pump. One valve feeds the cylinder and the other the rads. However it's somewhere close to there that the 22mm pipe ends. All the tails are 15mm, and all the pipework on the landing which is next to the cupboard is also all 15mm. This pipework then feeds the front 2 bedrooms as well as the downstairs hall rad and hopefully a new rad to be put in the living room which currently has no heat in it. The entire downstairs of the house is heated by one 700x1100 (ish) double panel no fins rad in the dining room next to the huge patio doors, and one 600x1600 single no fins in the hall!
Am I going to need 22mm run to replace that 15mm?
It shouldn't be too much of an issue to do as the floor on the landing and back bedroom (above boiler and also the room with the cupboard) is all easy to get up. It's just that the 15mm feed that goes to the hall rad downstairs goes under the office carpet which was only put down a few weeks ago.
3) Am I correct in understanding that condensing boilers are most efficient when the return is less than 55C? The gumpf from some of the WC programmers suggests that the savings they claim are based around keeping the boiler at it's most efficient for longer in turn meaning rads will be warm but not hot but maintaining a more even temp.
4) Payment. The only way we can do this is to put it on to a 0% card. I asked the bank for the money and was told that they would happily give it to me after they did a revaluation on the house (£200), paid a product fee (£300) and then paid the 5.5% interest rate. Hardly worth it when compared to the card that we can pay off only only have the 2.8% balance transfer charge to pay on top.
The problem is that not many guys take cards, larger groups do like Smith & Byford but the guy who did one of my rads and some bits for my brother, who is a nice guy and works well doesn't take it. He'd probably be cheaper and let me help out with removing the old kit and nailing the new rads up too but we have no other way of paying.
Do you plumbers find that causes you problems or have you got ways of taking cards even if you typically only take transfers/cash/cheque?
5) I think that's it for now. I know the guys that come to quote will no doubt answer them all, but I like to go into these things with a little idea of what kind of things are good or bad answers.
Thanks 🙂
EDIT: one more thing but it should probably be in the plumbing forum. With my bathroom refurb we fitted a Trevi Boost which suited our circumstances. I read that Trevi do a kit to convert to a Therm but can't seem to find it. Any ideas?
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