Evohome questions

[KJ1978]

Hi all

I am thinking about fitting Evohome in my house but have a few plumbing questions. I'm an electrician myself and have connected many different central heating systems, so that side of things should present no issues.

Current setup is Megaflo with Potterton boiler running 16 radiators, Honeywell Smartfit controls being used for the Central Heating only.

The issues I have is that the Smartfit valve for the central heating is low voltage, and will therefore either need to be changed or forced open with HR92 on all rads. Seems to me best practice would be to have a 2 port valve fitted.

Second issue is that the bypass appears to be via radiators in the two bathrooms, I would rather have these rads on the Evohome system and not leave them open, would I first need to get a bypass valve fitted between flow and return in the cylinder cupboard? I never realised these rads were the bypass until I started looking into all this, I've always shut them down in the summer as the bathrooms would get too hot, I was never told not to when I bought the house brand new. It hasn't caused any problems in ten years but obviously the bypass is fitted for good reason.

Any help would be much appreciated.

[top brake]

Hi all

I am thinking about fitting Evohome in my house but have a few plumbing questions. I'm an electrician myself and have connected many different central heating systems, so that side of things should present no issues.

Current setup is Megaflo with Potterton boiler running 16 radiators, Honeywell Smartfit controls being used for the Central Heating only.

The issues I have is that the Smartfit valve for the central heating is low voltage, and will therefore either need to be changed or forced open with HR92 on all rads. Seems to me best practice would be to have a 2 port valve fitted.

Second issue is that the bypass appears to be via radiators in the two bathrooms, I would rather have these rads on the Evohome system and not leave them open, would I first need to get a bypass valve fitted between flow and return in the cylinder cupboard? I never realised these rads were the bypass until I started looking into all this, I've always shut them down in the summer as the bathrooms would get too hot, I was never told not to when I bought the house brand new. It hasn't caused any problems in ten years but obviously the bypass is fitted for good reason.

Any help would be much appreciated.

you can replace the smartfit valve(S) with Honeywell V4043

while you are at it yes it is recommended that you fit an automatic bypass valve DU144 or DU145

there are several ways you can apply evohome to existing systems, these are detailed in the installation guide appendix together with wiring diagrams

I would recommend that you go through the youlearn.honeywelluk.com online training modules

all the best

[KJ1978]

Thanks for your reply, I've looked at the installation guide, and the wiring is straight forward. I will take a look at the youlearn site. I was kind of hoping I could swap the Smartfit valve head for a 230v head to minimise the amount of plumbing work needed.

This bypass is causing me a headache, as I say I have a bypass pipe that I'm sure feeds the radiators in the bathrooms, there is no valve on that pipe. I'm not sure whether I just need to put a valve on the existing bypass pipe or T new pipes into the flow and return and put the valve on those?

These plumbing aspects are not something I want to do myself but would like to know what I need to get done before I start fitting the Evohome system.

[top brake]

Thanks for your reply, I've looked at the installation guide, and the wiring is straight forward. I will take a look at the youlearn site. I was kind of hoping I could swap the Smartfit valve head for a 230v head to minimise the amount of plumbing work needed.

This bypass is causing me a headache, as I say I have a bypass pipe that I'm sure feeds the radiators in the bathrooms, there is no valve on that pipe. I'm not sure whether I just need to put a valve on the existing bypass pipe or T new pipes into the flow and return and put the valve on those?

These plumbing aspects are not something I want to do myself but would like to know what I need to get done before I start fitting the Evohome system.

Heads not interchangeable as bodies are different. Can you share a picture of your pipe work please?

[KJ1978]

[KJ1978]

From left to right - Flow - Return - Bypass- Heating Flow

[KJ1978]

Not sure if relevant but I'm sure the two radiators in the bathrooms which are connected to the bypass are T'd off as they are in smaller (12mm I think) PVC pipe.

[top brake]

From left to right - Flow - Return - Bypass- Heating Flow

Hard to advise on this really but the right hand valve is a 230v V4043 so suitable.

I would recommend getting an evohome specialist in to install your system

[The EVOHOME Shop]

Hard to advise on this really but the right hand valve is a 230v V4043 so suitable.

I would recommend getting an evohome specialist in to install your system

The V4043 valve has been installed as the safety for the Megaflo. As TB says, if you are not capable of doing this, Google 'Honeywell Find An Installer' and choose a Connected Specialist. If you are struggling to get hold of someone, give me a call and I can recommend someone we know in your area.

[KJ1978]

I'm more than capable of doing this, I've connected way more complicated heating systems than this with no problems at all. Just need a plumber to fit an auto bypass valve and maybe change that Smartfit 2 way valve, although I have been informed that I can just manually open the Smartfit valve and leave it open, then use the wireless relay to fire the boiler. Or as an alternative I've been informed that there is a 230v valve available, not made by Honeywell, from which the valve head can be swapped with the Smartfit valve head.

The V4043 in this case is connected as both a safety valve and as the hot water valve. There's no Smartfit valve controlling the hot water, I'm fully aware of the safety features of a Megaflo, I've connected hundreds of them.

[The EVOHOME Shop]

I'm more than capable of doing this, I've connected way more complicated heating systems than this with no problems at all. Just need a plumber to fit an auto bypass valve and maybe change that Smartfit 2 way valve, although I have been informed that I can just manually open the Smartfit valve and leave it open, then use the wireless relay to fire the boiler. Or as an alternative I've been informed that there is a 230v valve available, not made by Honeywell, from which the valve head can be swapped with the Smartfit valve head.

The V4043 in this case is connected as both a safety valve and as the hot water valve. There's no Smartfit valve controlling the hot water, I'm fully aware of the safety features of a Megaflo, I've connected hundreds of them.

Cool, I wasn't trying to dumb you down mate (I should have read the thread at the top better) - evohome is about as basic as heating system wiring gets.

From the pics you have a 3 port valve smartfit system? If it was my house, I would try and fit HR92's to all rads, convert this system to a figure 4 set-up by removing the 3 port valve and re-pipe the system adding the bypass at the same time. Really wouldn't take much to do this - few hours tops.

[KJ1978]

No worries mate. I have to apologise, that does seem to be a Smartift mid position valve so it's not an s-plan after all. As I said I'm not familiar with the Smartift range.

Not sure what you mean by a figure 4 setup, but I do intend to fit HR92 on every rad and get the auto bypass fitted.

[KJ1978]

I see what you mean by figure 4 now, the diagram in the manual. Regarding that diagram, surely the valve is labeled up wrong should be a V4043 not V4073 for the hot water control?

Screenshot_2016-02-05-21-15-38.jpg

[KJ1978]

Further to this if I'm using figure 4, which I have pretty much intended to do all along, can the Smartfit 3 port valve head be opened manually in the same way as the V4043 valves can be, maybe by removing the head and opening manually? Then no need to actually remove the valve just leave open?

[The EVOHOME Shop]

Further to this if I'm using figure 4, which I have pretty much intended to do all along, can the Smartfit 3 port valve head be opened manually in the same way as the V4043 valves can be, maybe by removing the head and opening manually? Then no need to actually remove the valve just leave open?

Sadly not, removal is the only way. Maybe refer to the new evohome Installation Guide, as the old one feature some typing errors - http://www.honeywelluk.com/Documents...stallation.pdf