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James, Developer
Category: HVAC
Satisfied Customers: 6938
Experience:  I have a portfolio of renovated houses, including DIY projects from installing bathrooms and new heating systems to rewiring.
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I have recently had a new vaillant 938 installed with two

Customer Question

hello, I have recently had a new vaillant 938 installed with two vrf 350 programmers/thermostats for a 2 zone system. Sadly the installers do not know how to set these up and cannot access the engineer sub menu. please help
JA: What's the brand and model of your thermostat? How old is it?
Customer: it is a vaillant vrf 350 it is brand new
JA: How long has this been going on with your thermostat? What have you tried so far?
Customer: i cant try anything I cannit access the sub menu
JA: Anything else we should know to help you best?
Customer: no
Submitted: 21 days ago.
Category: HVAC
Expert:  James replied 20 days ago.

Hello and welcome to JustAnswer!
This is James, I'm an appliance repair technician with over 10 years of experience, and I'll be assisting you today.

Sorry to hear your appliance is having issues, please stand by while I find the answer for you, this is not an immediate service however I will try and respond as soon as possible.
If the engineers do not know have to configure the stat, its advisable they fit one they are familiar with as you need to be confident they are correctly installed.

Expert:  James replied 20 days ago.

The installation guide for the VRF350 can be found here, page 22 details how to use the system\installer menu.

Customer: replied 20 days ago.
This does not tell me how to set it up on a two zone system, both thermostats are on heating 1, they are not seeing zone two. where are these settings or how should the thermostat display appear to reflect to heating zones?
Expert:  James replied 20 days ago.

Your going to need to get a heating engineer out if you can not follow the installation process outlined.

Engineers not familiar with the system should not be installing it, so would go back to them and get them contract \ subco someone who can come in and commission the system properly, as your going to end up with a load of problems trying to bodg this yourself.

Customer: replied 20 days ago.
I appreciate that, however those instructions do not tell me how to get into the sub menus or codes required. You have been of no use sadly
Expert:  James replied 20 days ago.

Your going to need to go back to the start determine how your wiring centre is setup and then determine how your VRF should be wired, this is not a configuration issue but rather a wiring one from what you have said.

Start by ensuring your 24V RT is hooked into the wiring centre so you have demand then your demand for heat is just calling the zone valve to open and closing the RT circuit for the boiler to start.

With regard to the "installer" this is explained at the top of heat heading eg Menu → Installer level → System configuration, the default code is 0000.

Have a good day.