Viessman Boilers can anybody in Kent install them properly?

[Giles Barford]

Hi,

I've had a 200W Viessman boiler for about a year. As the boiler goes it is not bad but the installation is a bit rubbish.

I went through the Viessman website and used the guy they recommended to do the job. Since the boiler has gone in I've had leaking pipework under the boiler I think. The rest of the pipework was pressure tested, new cylinder, pressure flush etc, prior to putting the new boiler in. The guy who did the install basically refused to come back and fix it.

I've had another Viessman engineer come out. He looked at the install and spent a lot of time swearing about the quality of the workmanship of the installers. Since he looked at the system my heating comes on at the same time as the hot water. Not great in this hot weather. I don't think the problem is the fault of the second guy, more the Jenga tower left by the installer. He did tighten up some pipework under the builder, which might have solved the leak.

I've contacted Viessman, who just stick to the line that their installers are independent contractors. I've even had them do the 1-year service but they refuse to help regarding the installation of the system. Just stick to the line, we just sell the boilers.

At the moment I'm considering ripping out the Viessman and putting in a Bosch. At least there seems to be good knowledge of them in the trade.

Happy to supply any details of the install. I'm trying to work out whether to persist with this boiler and what needs to be done to get it working right. I can probably supply diagrams of the system install and wiring.

 

[muggles]

If you've got system problems putting a new boiler in won't fix it. Some photos of the present installation would help.

 

[Giles Barford]

Hi,

Apologies for my terminology I'm learning more about boilers than I want but probably not enough to keep up all the time.

Hopefully, I don't have system problems (cross fingers). My pressure drops only seem to occur when it is cold, so it hard to test at the moment. I have water track marks under the boiler on that electric valve and damp patches. These have now been tightened. Hopefully, that is the pressure drop sorted. Although I'm not counting my chickens.

The boiler and cylinder were moved from the kitchen into the garage so there is a fair bit of new pipe.

The main problem I have right now is the heating coming on when the hot water comes on. We have weather compensation, so the pump runs all the time. If the hot water comes on it seems to pull the 80C water around the central heating system even when it is supposed to be 18C and the ambient is 22C. I've seen the whole system get to 90C on the boiler diagnostics.

We had problems with the hot water during install. It did not work at all for a while. Hot water reading on boiler says 14C when the thermostat on the tank calls for hot water and 75.2C (once tank up to temp). Obviously, on the tank temperature sensor is doing the setting of temp. The second opinion engineer wound it up to 65C and the house just keep heating up via data. Now I've turned it back to 45C it seems to have improved the situation, but I don't think it is right.

The second opinion engineer left the condensate pipe disconnected. He was swearing about the placement of the electric valve. He has told me that the tank is wired up wrong. Although I'm not totally sure who to believe.

Another problem we have is water pressure. I think this is due to something strange in our street. However, occasionally I'm having a shower and the water stops completely. The second opinion engineer says it might be due to the pressure balance being mounted upside down.

Oh that is the incoming water pipe. Installation engineer mounted handily right where the bath side should go. I've tried to adjust it and flip round so I can start to get side on the bath.

I've tried to get the installation engineer to come back. He keeps wanting to charge me for visit. We even agreed that I would pay him for a service, but he still did not manage to arrange a date. It is a bit of a drive for him and I understand people got to make a living. However, if he screwed the install then it hardly my fault.

Let me know if you want any more diagrams/pics. I'm guessing somebody will need wiring diagram for hot water sensors. That might be a weekend project.

Regards

Giles

 

[Deleted member 267285]

No images attached there.

 

[picasso]

You have a 4 pipe hot water priority set up that looks like its been royaly f**cked up, either get the installer back or tell him you will get it sorted and send him the bill, viessmann give clear wiring guides that should have given a problem free install.

 

[Giles Barford]

Hi,

Thank you much appreciated. Hopefully, people can see my images now.

I would like a few more people to comment. I'm pretty livid with the original installer, and trust is fairly shot.

Regards

Giles

 

[sxturbo]

I'm no pro, but it's a bit of a mess, certain things I wouldn't have done personally (like placing the valve there for a start)

Ball valve handle been cut, why? should have just spun it 180 degrees,

 

[Gasguru]

Have you got the building control notices for the boiler and cylinder install?
What are those clips doing on the filling loop?
Rough as install, don't be fooled by the temperature markings on those cylinder stats...they are always completely inaccurate.

 

[Giles Barford]

Hi,

I'm not sure what you mean by clips on the filling loop.

The boiler has building control but it looks like the cylinder might have been skipped . Yeah, I kinda guessed that stat was inaccurate, at the moment nothing reads the tank water accurate. I know with a Viessman cylinder it would have a stat weird straight to the boiler and then I would be able to read water temp. However, obviously, this is not possible with the current setup as the stat just give on-off.

I had to cut the ball valve. When it was spun 180 it would have fouled where I plan to box in the bath. It fouls the pipes when on this angle, probably needs to be moved at some point as it is in the most inconvenient place they could have put it. I'll have to sort that down the line but at least I can put side on the bath soon. I really just took that picture to show the mains pipe, so people can comment on the pressure issue.

Regards

Giles

 

[ianmcd]

The boiler has not been installed correctly, I had exactly the same on my patch and the customer had it for over 5 years before I pointed out that the boiler was not installed properly, took a major shift to sort it but a happy customer at the end of the day, you have a 4 pipe system, you shouldnt have a zone valve, it is all controlled from inside the boiler

 

[picasso]

Unfortunately the 2 port is needed for reg compliance.

 

[ianmcd]

Unfortunately the 2 port is needed for reg compliance.

Not if you use the Viessman HW cylinder NTC