All 3 are in series when you test for continuity you put an ohm meter across the two pins (preferably one that beeps). This can be done while the boiler is running or with no power applied.
It is possible that both are open circuit but unlikely. More likely you are not geting a good contact with your probes. Clip leed across both momentarily to see what happens, if boiler fires you've found it is one of those two, then remove one clip leed.
If the aps proves to be the problem it may not be, it may be fan or sensing tubes in need of a clean.
Man at Swiftflow is probably feding you enough info to get you off the line because of your level of questioning, he doesn't want to have to teach you so much.
It is quite possible that it is neither the aps or the high lmit stat but the gas valve or the pcb, you have to keep an open mind for a lot longer to get the real culprit.
APS failure tends to be intermittent in the first instance. Tap aps to prove an intermitent fault with it, definately invest in one of it sometimes works after a tap, sometimes works without a tap sometimes doesn't work at all. Sense tubes blocked is more likely in first instance, aps behaving corrctly for the information fed to it.
It is possible that both are open circuit but unlikely. More likely you are not geting a good contact with your probes. Clip leed across both momentarily to see what happens, if boiler fires you've found it is one of those two, then remove one clip leed.
If the aps proves to be the problem it may not be, it may be fan or sensing tubes in need of a clean.
Man at Swiftflow is probably feding you enough info to get you off the line because of your level of questioning, he doesn't want to have to teach you so much.
It is quite possible that it is neither the aps or the high lmit stat but the gas valve or the pcb, you have to keep an open mind for a lot longer to get the real culprit.
APS failure tends to be intermittent in the first instance. Tap aps to prove an intermitent fault with it, definately invest in one of it sometimes works after a tap, sometimes works without a tap sometimes doesn't work at all. Sense tubes blocked is more likely in first instance, aps behaving corrctly for the information fed to it.