Hi
I have a few questions about my Ecotec 637 Plus installation (about 3 years old). I’ve tried to break them down clearly as there’s quite a lot.
1) I have been upgrading our TRVs and central thermostat to an Evohome connected system. I would like to put all valves on this system but know that for some boilers without a built in bypass it’s important to have one rad fully open all the time in case there is an error which calls for the boiler to be on while all other TRVs are switched off, so the water has somewhere to go.
QUESTION: Do I need to have an automatic bypass valve fitted in order to be able to safely have all valves as TRVs, or does the Ecotec 637 Plus have its own automatic bypass built in? I have noticed a couple of references to a bypass (e.g. diverter valve with bypass) in the manual but am not sure if this is the right type of bypass.
2) I have noticed that both CH and HW are output by the same pipe from the boiler, before a split to their individual motorised valves. So whenever either is on the boiler shows the CH (radiator) symbol, but it never shows the HW (tap) symbol.
QUESTION: Is this in itself a problem? Is it in fact a benefit, allowing us to run heating and HW at the same time?
3) My installer used the previous installation's existing timer control to wire up the boiler controls. For the HW, behaviour is as expected: it controls when we want to heat the HW in a megaflo tank.
For the CH, it's left as always on, connected to a Honeywell relay to a wireless thermostat which tells the boiler when heat is required. The motorised valve is connected to the old controller rather than the relay, so the CH valve is always open.
QUESTION: Does the always-open CH motorised valve, and CH&HW using the same output of the boiler, mean that when there is a call for HW but not for CH, the CH circuit will be fed hot water anyway? I have noticed a few times our towel rail being on when the CH was switched off - could this be why? Is this a problem? It doesn’t sound ideal.
3) I intend to rewire the controls to fully utilise the features of Evohome, and to take out of service the very old timer control which seems unnecessary and will fail at some point. When I wire the system correctly, it will mean that the CH motorised valve is controlled by the Honeywell controller rather than staying open at all times.
QUESTION: Is that the correct operation, and will that actually solve the issues in 3) above?
Thanking you for your support!
Tom
I have a few questions about my Ecotec 637 Plus installation (about 3 years old). I’ve tried to break them down clearly as there’s quite a lot.
1) I have been upgrading our TRVs and central thermostat to an Evohome connected system. I would like to put all valves on this system but know that for some boilers without a built in bypass it’s important to have one rad fully open all the time in case there is an error which calls for the boiler to be on while all other TRVs are switched off, so the water has somewhere to go.
QUESTION: Do I need to have an automatic bypass valve fitted in order to be able to safely have all valves as TRVs, or does the Ecotec 637 Plus have its own automatic bypass built in? I have noticed a couple of references to a bypass (e.g. diverter valve with bypass) in the manual but am not sure if this is the right type of bypass.
2) I have noticed that both CH and HW are output by the same pipe from the boiler, before a split to their individual motorised valves. So whenever either is on the boiler shows the CH (radiator) symbol, but it never shows the HW (tap) symbol.
QUESTION: Is this in itself a problem? Is it in fact a benefit, allowing us to run heating and HW at the same time?
3) My installer used the previous installation's existing timer control to wire up the boiler controls. For the HW, behaviour is as expected: it controls when we want to heat the HW in a megaflo tank.
For the CH, it's left as always on, connected to a Honeywell relay to a wireless thermostat which tells the boiler when heat is required. The motorised valve is connected to the old controller rather than the relay, so the CH valve is always open.
QUESTION: Does the always-open CH motorised valve, and CH&HW using the same output of the boiler, mean that when there is a call for HW but not for CH, the CH circuit will be fed hot water anyway? I have noticed a few times our towel rail being on when the CH was switched off - could this be why? Is this a problem? It doesn’t sound ideal.
3) I intend to rewire the controls to fully utilise the features of Evohome, and to take out of service the very old timer control which seems unnecessary and will fail at some point. When I wire the system correctly, it will mean that the CH motorised valve is controlled by the Honeywell controller rather than staying open at all times.
QUESTION: Is that the correct operation, and will that actually solve the issues in 3) above?
Thanking you for your support!
Tom
