Hi. I am having a new boiler fitted soon and they have offered to fit new BULLDOG trv"s. I already have Mistral 11 trv"s fitted, but they are a few (maybe 6 or 7 ) years old. I have never had a lot of faith in them, operational wise, but that could just be me. Does anyone have an informed opinion of whether to stick with the Mistrals, get the Bulldogs, or have something better fitted? Thanks in advance.
Think Pegler make the Bulldog trv's for Plumb Centre There are two types of TRV's wax sensor & liquid sensor, the liquid sensor is more responsive to temperature changes & are more accurate.
I know nothing about Mistrals, but TRVs in general are quite prone to sticking after a few years. Having said that, 6 to 7 years is not old, but give it a few more years and you can expect some to cause issues (which, in the majority of cases, you'll be able to sort with a hammer...). Bit, if their price is reasonable, it is certainly the time to do it - system drained down, etc. Is this not something you'd consider doing yourself? If so, then by all means consider leaving it until they start to cause issues, then drain down and swap them all. This is likely not going to be for 5 or more years. New inhibitor in system on refill.
So why is that ? Very often trv's do not operate as quick as quick as we would like (auto turning up or turning down). we will sense a change in temperature before the trv. Mistral,terrier and bulldog valve bodys look the same,as mentioned bulldog are a named brand for plumb center.So the valve bodys are the same maybe a different shade of chrome but with different sensors.often better looking and easier to grip. Your installer could just screw new sensors on your existing valve bodys . Personally i prefer trv's made by danfoss the ras-c2 is their contract version and if the sensor is mounted horizontally they give good results. I have seen the honeywell evohome wifi trv system and it looks impressive.
The minimum is the bedrooms, but you dont have to have it done as the home owner you have every right to refuse. It is best practice to have them fitted and a boiler chane is a very oportune time to do it. If its a convert to combi then I like to change all the valves to reduce the risks of leaks when pressurising a system.